From de2baa880de3d5eecf2e46ebdee0aaeb565f5917 Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Fri, 14 Oct 2022 10:39:18 -0400 Subject: selftests/vm: use memfd for uffd hugetlb tests Patch series "selftests/vm: Drop hugetlb mntpoint in run_vmtests.sh", v2. Clean the code up so we can use the same memfd for both hugetlb and shmem which is cleaner. This patch (of 4): We already used memfd for shmem test, move it forward with hugetlb too so that we don't need user to specify the hugetlb file path explicitly when running hugetlb shared tests. Link: https://lkml.kernel.org/r/20221014143921.93887-1-peterx@redhat.com Link: https://lkml.kernel.org/r/20221014143921.93887-2-peterx@redhat.com Signed-off-by: Peter Xu Reviewed-by: Axel Rasmussen Cc: Axel Rasmussen Cc: Mike Kravetz Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/userfaultfd.c | 62 +++++++++++--------------------- 1 file changed, 21 insertions(+), 41 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c index 297f250c1d95..7f22844ed704 100644 --- a/tools/testing/selftests/vm/userfaultfd.c +++ b/tools/testing/selftests/vm/userfaultfd.c @@ -93,10 +93,8 @@ static volatile bool test_uffdio_zeropage_eexist = true; static bool test_uffdio_wp = true; /* Whether to test uffd minor faults */ static bool test_uffdio_minor = false; - static bool map_shared; -static int shm_fd; -static int huge_fd; +static int mem_fd; static unsigned long long *count_verify; static int uffd = -1; static int uffd_flags, finished, *pipefd; @@ -143,7 +141,7 @@ const char *examples = "# Run hugetlb memory test on 256MiB region with 50 bounces:\n" "./userfaultfd hugetlb 256 50\n\n" "# Run the same hugetlb test but using shared file:\n" - "./userfaultfd hugetlb_shared 256 50 /dev/hugepages/hugefile\n\n" + "./userfaultfd hugetlb_shared 256 50\n\n" "# 10MiB-~6GiB 999 bounces anonymous test, " "continue forever unless an error triggers\n" "while ./userfaultfd anon $[RANDOM % 6000 + 10] 999; do true; done\n\n"; @@ -260,35 +258,21 @@ static void hugetlb_release_pages(char *rel_area) static void hugetlb_allocate_area(void **alloc_area, bool is_src) { + off_t size = nr_pages * page_size; + off_t offset = is_src ? 0 : size; void *area_alias = NULL; char **alloc_area_alias; - if (!map_shared) - *alloc_area = mmap(NULL, - nr_pages * page_size, - PROT_READ | PROT_WRITE, - MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB | - (is_src ? 0 : MAP_NORESERVE), - -1, - 0); - else - *alloc_area = mmap(NULL, - nr_pages * page_size, - PROT_READ | PROT_WRITE, - MAP_SHARED | - (is_src ? 0 : MAP_NORESERVE), - huge_fd, - is_src ? 0 : nr_pages * page_size); + *alloc_area = mmap(NULL, size, PROT_READ | PROT_WRITE, + (map_shared ? MAP_SHARED : MAP_PRIVATE) | + (is_src ? 0 : MAP_NORESERVE), + mem_fd, offset); if (*alloc_area == MAP_FAILED) err("mmap of hugetlbfs file failed"); if (map_shared) { - area_alias = mmap(NULL, - nr_pages * page_size, - PROT_READ | PROT_WRITE, - MAP_SHARED, - huge_fd, - is_src ? 0 : nr_pages * page_size); + area_alias = mmap(NULL, size, PROT_READ | PROT_WRITE, + MAP_SHARED, mem_fd, offset); if (area_alias == MAP_FAILED) err("mmap of hugetlb file alias failed"); } @@ -334,14 +318,14 @@ static void shmem_allocate_area(void **alloc_area, bool is_src) } *alloc_area = mmap(p, bytes, PROT_READ | PROT_WRITE, MAP_SHARED, - shm_fd, offset); + mem_fd, offset); if (*alloc_area == MAP_FAILED) err("mmap of memfd failed"); if (test_collapse && *alloc_area != p) err("mmap of memfd failed at %p", p); area_alias = mmap(p_alias, bytes, PROT_READ | PROT_WRITE, MAP_SHARED, - shm_fd, offset); + mem_fd, offset); if (area_alias == MAP_FAILED) err("mmap of memfd alias failed"); if (test_collapse && area_alias != p_alias) @@ -1841,21 +1825,17 @@ int main(int argc, char **argv) } nr_pages = nr_pages_per_cpu * nr_cpus; - if (test_type == TEST_HUGETLB && map_shared) { - if (argc < 5) - usage(); - huge_fd = open(argv[4], O_CREAT | O_RDWR, 0755); - if (huge_fd < 0) - err("Open of %s failed", argv[4]); - if (ftruncate(huge_fd, 0)) - err("ftruncate %s to size 0 failed", argv[4]); - } else if (test_type == TEST_SHMEM) { - shm_fd = memfd_create(argv[0], 0); - if (shm_fd < 0) + if (test_type == TEST_SHMEM || test_type == TEST_HUGETLB) { + unsigned int memfd_flags = 0; + + if (test_type == TEST_HUGETLB) + memfd_flags = MFD_HUGETLB; + mem_fd = memfd_create(argv[0], memfd_flags); + if (mem_fd < 0) err("memfd_create"); - if (ftruncate(shm_fd, nr_pages * page_size * 2)) + if (ftruncate(mem_fd, nr_pages * page_size * 2)) err("ftruncate"); - if (fallocate(shm_fd, + if (fallocate(mem_fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, 0, nr_pages * page_size * 2)) err("fallocate"); -- cgit v1.2.3 From 62f33fa228003a419a9484eed5133447a280387c Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Fri, 14 Oct 2022 10:39:19 -0400 Subject: selftests/vm: use memfd for hugetlb-madvise test For dropping the hugetlb mountpoint in run_vmtests.sh. Since no parameter is needed, drop USAGE too. Link: https://lkml.kernel.org/r/20221014143921.93887-3-peterx@redhat.com Signed-off-by: Peter Xu Cc: Axel Rasmussen Cc: Mike Kravetz Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/hugetlb-madvise.c | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/vm/hugetlb-madvise.c b/tools/testing/selftests/vm/hugetlb-madvise.c index 3c9943131881..f96435b70986 100644 --- a/tools/testing/selftests/vm/hugetlb-madvise.c +++ b/tools/testing/selftests/vm/hugetlb-madvise.c @@ -12,6 +12,7 @@ * directory. */ +#define _GNU_SOURCE #include #include #include @@ -19,7 +20,6 @@ #define __USE_GNU #include -#define USAGE "USAGE: %s \n" #define MIN_FREE_PAGES 20 #define NR_HUGE_PAGES 10 /* common number of pages to map/allocate */ @@ -103,11 +103,6 @@ int main(int argc, char **argv) int fd; int ret; - if (argc != 2) { - printf(USAGE, argv[0]); - exit(1); - } - huge_page_size = default_huge_page_size(); if (!huge_page_size) { printf("Unable to determine huge page size, exiting!\n"); @@ -125,9 +120,9 @@ int main(int argc, char **argv) exit(1); } - fd = open(argv[1], O_CREAT | O_RDWR, 0755); + fd = memfd_create(argv[0], MFD_HUGETLB); if (fd < 0) { - perror("Open failed"); + perror("memfd_create() failed"); exit(1); } @@ -406,6 +401,5 @@ int main(int argc, char **argv) (void)munmap(addr2, NR_HUGE_PAGES * huge_page_size); close(fd); - unlink(argv[1]); return 0; } -- cgit v1.2.3 From 4705700d4fef3178e93230f53c2c528569744bb6 Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Fri, 14 Oct 2022 10:40:13 -0400 Subject: selftests/vm: use memfd for hugepage-mremap test For dropping the hugetlb mountpoint in run_vmtests.sh. Cleaned it up a little bit around the changed codes. Link: https://lkml.kernel.org/r/20221014144013.94027-1-peterx@redhat.com Signed-off-by: Peter Xu Cc: Axel Rasmussen Cc: Mike Kravetz Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/hugepage-mremap.c | 21 +++++++++------------ 1 file changed, 9 insertions(+), 12 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/vm/hugepage-mremap.c b/tools/testing/selftests/vm/hugepage-mremap.c index e63a0214f639..e53b5eaa8fce 100644 --- a/tools/testing/selftests/vm/hugepage-mremap.c +++ b/tools/testing/selftests/vm/hugepage-mremap.c @@ -22,6 +22,7 @@ #include /* Definition of SYS_* constants */ #include #include +#include #define DEFAULT_LENGTH_MB 10UL #define MB_TO_BYTES(x) (x * 1024 * 1024) @@ -108,26 +109,23 @@ static void register_region_with_uffd(char *addr, size_t len) int main(int argc, char *argv[]) { size_t length = 0; + int ret = 0, fd; - if (argc != 2 && argc != 3) { - printf("Usage: %s [length_in_MB] \n", argv[0]); + if (argc >= 2 && !strcmp(argv[1], "-h")) { + printf("Usage: %s [length_in_MB]\n", argv[0]); exit(1); } /* Read memory length as the first arg if valid, otherwise fallback to * the default length. */ - if (argc == 3) - length = argc > 2 ? (size_t)atoi(argv[1]) : 0UL; + if (argc >= 2) + length = (size_t)atoi(argv[1]); + else + length = DEFAULT_LENGTH_MB; - length = length > 0 ? length : DEFAULT_LENGTH_MB; length = MB_TO_BYTES(length); - - int ret = 0; - - /* last arg is the hugetlb file name */ - int fd = open(argv[argc-1], O_CREAT | O_RDWR, 0755); - + fd = memfd_create(argv[0], MFD_HUGETLB); if (fd < 0) { perror("Open failed"); exit(1); @@ -185,7 +183,6 @@ int main(int argc, char *argv[]) } close(fd); - unlink(argv[argc-1]); return ret; } -- cgit v1.2.3 From 0796c7b8be84415994fa37e9a022e5595d915dd7 Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Fri, 14 Oct 2022 10:40:15 -0400 Subject: selftests/vm: drop mnt point for hugetlb in run_vmtests.sh After converting all the three relevant testcases (uffd, madvise, mremap) to use memfd, no test will need the hugetlb mount point anymore. Drop the code. Link: https://lkml.kernel.org/r/20221014144015.94039-1-peterx@redhat.com Signed-off-by: Peter Xu Reviewed-by: Axel Rasmussen Cc: Mike Kravetz Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/run_vmtests.sh | 18 +++--------------- 1 file changed, 3 insertions(+), 15 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/vm/run_vmtests.sh b/tools/testing/selftests/vm/run_vmtests.sh index e780e76c26b8..0dc9f545a32d 100755 --- a/tools/testing/selftests/vm/run_vmtests.sh +++ b/tools/testing/selftests/vm/run_vmtests.sh @@ -5,7 +5,6 @@ # Kselftest framework requirement - SKIP code is 4. ksft_skip=4 -mnt=./huge exitcode=0 #get huge pagesize and freepages from /proc/meminfo @@ -84,9 +83,6 @@ run_test() { fi } -mkdir "$mnt" -mount -t hugetlbfs none "$mnt" - run_test ./hugepage-mmap shmmax=$(cat /proc/sys/kernel/shmmax) @@ -98,14 +94,9 @@ echo "$shmmax" > /proc/sys/kernel/shmmax echo "$shmall" > /proc/sys/kernel/shmall run_test ./map_hugetlb - -run_test ./hugepage-mremap "$mnt"/huge_mremap -rm -f "$mnt"/huge_mremap - +run_test ./hugepage-mremap run_test ./hugepage-vmemmap - -run_test ./hugetlb-madvise "$mnt"/madvise-test -rm -f "$mnt"/madvise-test +run_test ./hugetlb-madvise echo "NOTE: The above hugetlb tests provide minimal coverage. Use" echo " https://github.com/libhugetlbfs/libhugetlbfs.git for" @@ -126,14 +117,11 @@ for mod in "${uffd_mods[@]}"; do # Hugetlb tests require source and destination huge pages. Pass in half # the size ($half_ufd_size_MB), which is used for *each*. run_test ./userfaultfd hugetlb${mod} "$half_ufd_size_MB" 32 - run_test ./userfaultfd hugetlb_shared${mod} "$half_ufd_size_MB" 32 "$mnt"/uffd-test - rm -f "$mnt"/uffd-test + run_test ./userfaultfd hugetlb_shared${mod} "$half_ufd_size_MB" 32 run_test ./userfaultfd shmem${mod} 20 16 done #cleanup -umount "$mnt" -rm -rf "$mnt" echo "$nr_hugepgs" > /proc/sys/vm/nr_hugepages run_test ./compaction_test -- cgit v1.2.3 From 69c66add566395eaf4c08cb5975b45dec70dbe85 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Tue, 27 Sep 2022 13:01:14 +0200 Subject: selftests/vm: anon_cow: test COW handling of anonymous memory Patch series "selftests/vm: test COW handling of anonymous memory". This is my current set of tests for testing COW handling of anonymous memory, especially when interacting with GUP. I developed these tests while working on PageAnonExclusive and managed to clean them up just now. On current upstream Linux, all tests pass except the hugetlb tests that rely on vmsplice -- these tests should pass as soon as vmsplice properly uses FOLL_PIN instead of FOLL_GET. I'm working on additional tests for COW handling in private mappings, focusing on long-term R/O pinning e.g., of the shared zeropage, pagecache pages and KSM pages. These tests, however, will go into a different file. So this is everything I have regarding tests for anonymous memory. This patch (of 7): Let's start adding tests for our COW handling of anonymous memory. We'll focus on basic tests that we can achieve without additional libraries or gup_test extensions. We'll add THP and hugetlb tests separately. [david@redhat.com: s/size_t/ssize_t/ on `cur', `total', `transferred';] Link: https://lkml.kernel.org/r/51302b9e-dc69-d709-3214-f23868028555@redhat.com Link: https://lkml.kernel.org/r/20220927110120.106906-1-david@redhat.com Link: https://lkml.kernel.org/r/20220927110120.106906-2-david@redhat.com Signed-off-by: David Hildenbrand Cc: Andrea Arcangeli Cc: Christoph von Recklinghausen Cc: Don Dutile Cc: Jason Gunthorpe Cc: John Hubbard Cc: Mike Rapoport Cc: Nadav Amit Cc: Peter Xu Cc: Shuah Khan Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/.gitignore | 1 + tools/testing/selftests/vm/Makefile | 4 +- tools/testing/selftests/vm/anon_cow.c | 401 ++++++++++++++++++++++++++++++ tools/testing/selftests/vm/run_vmtests.sh | 3 + tools/testing/selftests/vm/vm_util.c | 7 + tools/testing/selftests/vm/vm_util.h | 1 + 6 files changed, 416 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/vm/anon_cow.c (limited to 'tools') diff --git a/tools/testing/selftests/vm/.gitignore b/tools/testing/selftests/vm/.gitignore index 7b9dc2426f18..8a536c731e3c 100644 --- a/tools/testing/selftests/vm/.gitignore +++ b/tools/testing/selftests/vm/.gitignore @@ -1,4 +1,5 @@ # SPDX-License-Identifier: GPL-2.0-only +anon_cow hugepage-mmap hugepage-mremap hugepage-shm diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index 163c2fde3cb3..ad07d7a84c3e 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -25,7 +25,8 @@ MAKEFLAGS += --no-builtin-rules CFLAGS = -Wall -I $(top_srcdir) -I $(top_srcdir)/usr/include $(EXTRA_CFLAGS) $(KHDR_INCLUDES) LDLIBS = -lrt -lpthread -TEST_GEN_FILES = compaction_test +TEST_GEN_FILES = anon_cow +TEST_GEN_FILES += compaction_test TEST_GEN_FILES += gup_test TEST_GEN_FILES += hmm-tests TEST_GEN_FILES += hugetlb-madvise @@ -95,6 +96,7 @@ TEST_FILES += va_128TBswitch.sh include ../lib.mk +$(OUTPUT)/anon_cow: vm_util.c $(OUTPUT)/khugepaged: vm_util.c $(OUTPUT)/madv_populate: vm_util.c $(OUTPUT)/soft-dirty: vm_util.c diff --git a/tools/testing/selftests/vm/anon_cow.c b/tools/testing/selftests/vm/anon_cow.c new file mode 100644 index 000000000000..4613294af758 --- /dev/null +++ b/tools/testing/selftests/vm/anon_cow.c @@ -0,0 +1,401 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * COW (Copy On Write) tests for anonymous memory. + * + * Copyright 2022, Red Hat, Inc. + * + * Author(s): David Hildenbrand + */ +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "../kselftest.h" +#include "vm_util.h" + +static size_t pagesize; +static int pagemap_fd; + +struct comm_pipes { + int child_ready[2]; + int parent_ready[2]; +}; + +static int setup_comm_pipes(struct comm_pipes *comm_pipes) +{ + if (pipe(comm_pipes->child_ready) < 0) + return -errno; + if (pipe(comm_pipes->parent_ready) < 0) { + close(comm_pipes->child_ready[0]); + close(comm_pipes->child_ready[1]); + return -errno; + } + + return 0; +} + +static void close_comm_pipes(struct comm_pipes *comm_pipes) +{ + close(comm_pipes->child_ready[0]); + close(comm_pipes->child_ready[1]); + close(comm_pipes->parent_ready[0]); + close(comm_pipes->parent_ready[1]); +} + +static int child_memcmp_fn(char *mem, size_t size, + struct comm_pipes *comm_pipes) +{ + char *old = malloc(size); + char buf; + + /* Backup the original content. */ + memcpy(old, mem, size); + + /* Wait until the parent modified the page. */ + write(comm_pipes->child_ready[1], "0", 1); + while (read(comm_pipes->parent_ready[0], &buf, 1) != 1) + ; + + /* See if we still read the old values. */ + return memcmp(old, mem, size); +} + +static int child_vmsplice_memcmp_fn(char *mem, size_t size, + struct comm_pipes *comm_pipes) +{ + struct iovec iov = { + .iov_base = mem, + .iov_len = size, + }; + ssize_t cur, total, transferred; + char *old, *new; + int fds[2]; + char buf; + + old = malloc(size); + new = malloc(size); + + /* Backup the original content. */ + memcpy(old, mem, size); + + if (pipe(fds) < 0) + return -errno; + + /* Trigger a read-only pin. */ + transferred = vmsplice(fds[1], &iov, 1, 0); + if (transferred < 0) + return -errno; + if (transferred == 0) + return -EINVAL; + + /* Unmap it from our page tables. */ + if (munmap(mem, size) < 0) + return -errno; + + /* Wait until the parent modified it. */ + write(comm_pipes->child_ready[1], "0", 1); + while (read(comm_pipes->parent_ready[0], &buf, 1) != 1) + ; + + /* See if we still read the old values via the pipe. */ + for (total = 0; total < transferred; total += cur) { + cur = read(fds[0], new + total, transferred - total); + if (cur < 0) + return -errno; + } + + return memcmp(old, new, transferred); +} + +typedef int (*child_fn)(char *mem, size_t size, struct comm_pipes *comm_pipes); + +static void do_test_cow_in_parent(char *mem, size_t size, child_fn fn) +{ + struct comm_pipes comm_pipes; + char buf; + int ret; + + ret = setup_comm_pipes(&comm_pipes); + if (ret) { + ksft_test_result_fail("pipe() failed\n"); + return; + } + + ret = fork(); + if (ret < 0) { + ksft_test_result_fail("fork() failed\n"); + goto close_comm_pipes; + } else if (!ret) { + exit(fn(mem, size, &comm_pipes)); + } + + while (read(comm_pipes.child_ready[0], &buf, 1) != 1) + ; + /* Modify the page. */ + memset(mem, 0xff, size); + write(comm_pipes.parent_ready[1], "0", 1); + + wait(&ret); + if (WIFEXITED(ret)) + ret = WEXITSTATUS(ret); + else + ret = -EINVAL; + + ksft_test_result(!ret, "No leak from parent into child\n"); +close_comm_pipes: + close_comm_pipes(&comm_pipes); +} + +static void test_cow_in_parent(char *mem, size_t size) +{ + do_test_cow_in_parent(mem, size, child_memcmp_fn); +} + +static void test_vmsplice_in_child(char *mem, size_t size) +{ + do_test_cow_in_parent(mem, size, child_vmsplice_memcmp_fn); +} + +static void do_test_vmsplice_in_parent(char *mem, size_t size, + bool before_fork) +{ + struct iovec iov = { + .iov_base = mem, + .iov_len = size, + }; + ssize_t cur, total, transferred; + struct comm_pipes comm_pipes; + char *old, *new; + int ret, fds[2]; + char buf; + + old = malloc(size); + new = malloc(size); + + memcpy(old, mem, size); + + ret = setup_comm_pipes(&comm_pipes); + if (ret) { + ksft_test_result_fail("pipe() failed\n"); + goto free; + } + + if (pipe(fds) < 0) { + ksft_test_result_fail("pipe() failed\n"); + goto close_comm_pipes; + } + + if (before_fork) { + transferred = vmsplice(fds[1], &iov, 1, 0); + if (transferred <= 0) { + ksft_test_result_fail("vmsplice() failed\n"); + goto close_pipe; + } + } + + ret = fork(); + if (ret < 0) { + ksft_test_result_fail("fork() failed\n"); + goto close_pipe; + } else if (!ret) { + write(comm_pipes.child_ready[1], "0", 1); + while (read(comm_pipes.parent_ready[0], &buf, 1) != 1) + ; + /* Modify page content in the child. */ + memset(mem, 0xff, size); + exit(0); + } + + if (!before_fork) { + transferred = vmsplice(fds[1], &iov, 1, 0); + if (transferred <= 0) { + ksft_test_result_fail("vmsplice() failed\n"); + wait(&ret); + goto close_pipe; + } + } + + while (read(comm_pipes.child_ready[0], &buf, 1) != 1) + ; + if (munmap(mem, size) < 0) { + ksft_test_result_fail("munmap() failed\n"); + goto close_pipe; + } + write(comm_pipes.parent_ready[1], "0", 1); + + /* Wait until the child is done writing. */ + wait(&ret); + if (!WIFEXITED(ret)) { + ksft_test_result_fail("wait() failed\n"); + goto close_pipe; + } + + /* See if we still read the old values. */ + for (total = 0; total < transferred; total += cur) { + cur = read(fds[0], new + total, transferred - total); + if (cur < 0) { + ksft_test_result_fail("read() failed\n"); + goto close_pipe; + } + } + + ksft_test_result(!memcmp(old, new, transferred), + "No leak from child into parent\n"); +close_pipe: + close(fds[0]); + close(fds[1]); +close_comm_pipes: + close_comm_pipes(&comm_pipes); +free: + free(old); + free(new); +} + +static void test_vmsplice_before_fork(char *mem, size_t size) +{ + do_test_vmsplice_in_parent(mem, size, true); +} + +static void test_vmsplice_after_fork(char *mem, size_t size) +{ + do_test_vmsplice_in_parent(mem, size, false); +} + +typedef void (*test_fn)(char *mem, size_t size); + +static void do_run_with_base_page(test_fn fn, bool swapout) +{ + char *mem; + int ret; + + mem = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + return; + } + + ret = madvise(mem, pagesize, MADV_NOHUGEPAGE); + /* Ignore if not around on a kernel. */ + if (ret && errno != EINVAL) { + ksft_test_result_fail("MADV_NOHUGEPAGE failed\n"); + goto munmap; + } + + /* Populate a base page. */ + memset(mem, 0, pagesize); + + if (swapout) { + madvise(mem, pagesize, MADV_PAGEOUT); + if (!pagemap_is_swapped(pagemap_fd, mem)) { + ksft_test_result_skip("MADV_PAGEOUT did not work, is swap enabled?\n"); + goto munmap; + } + } + + fn(mem, pagesize); +munmap: + munmap(mem, pagesize); +} + +static void run_with_base_page(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with base page\n", desc); + do_run_with_base_page(fn, false); +} + +static void run_with_base_page_swap(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with swapped out base page\n", desc); + do_run_with_base_page(fn, true); +} + +struct test_case { + const char *desc; + test_fn fn; +}; + +static const struct test_case test_cases[] = { + /* + * Basic COW tests for fork() without any GUP. If we miss to break COW, + * either the child can observe modifications by the parent or the + * other way around. + */ + { + "Basic COW after fork()", + test_cow_in_parent, + }, + /* + * vmsplice() [R/O GUP] + unmap in the child; modify in the parent. If + * we miss to break COW, the child observes modifications by the parent. + * This is CVE-2020-29374 reported by Jann Horn. + */ + { + "vmsplice() + unmap in child", + test_vmsplice_in_child + }, + /* + * vmsplice() [R/O GUP] in parent before fork(), unmap in parent after + * fork(); modify in the child. If we miss to break COW, the parent + * observes modifications by the child. + */ + { + "vmsplice() before fork(), unmap in parent after fork()", + test_vmsplice_before_fork, + }, + /* + * vmsplice() [R/O GUP] + unmap in parent after fork(); modify in the + * child. If we miss to break COW, the parent observes modifications by + * the child. + */ + { + "vmsplice() + unmap in parent after fork()", + test_vmsplice_after_fork, + }, +}; + +static void run_test_case(struct test_case const *test_case) +{ + run_with_base_page(test_case->fn, test_case->desc); + run_with_base_page_swap(test_case->fn, test_case->desc); +} + +static void run_test_cases(void) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(test_cases); i++) + run_test_case(&test_cases[i]); +} + +int main(int argc, char **argv) +{ + int nr_test_cases = ARRAY_SIZE(test_cases); + int err; + + pagesize = getpagesize(); + + ksft_print_header(); + ksft_set_plan(nr_test_cases * 2); + + pagemap_fd = open("/proc/self/pagemap", O_RDONLY); + if (pagemap_fd < 0) + ksft_exit_fail_msg("opening pagemap failed\n"); + + run_test_cases(); + + err = ksft_get_fail_cnt(); + if (err) + ksft_exit_fail_msg("%d out of %d tests failed\n", + err, ksft_test_num()); + return ksft_exit_pass(); +} diff --git a/tools/testing/selftests/vm/run_vmtests.sh b/tools/testing/selftests/vm/run_vmtests.sh index 0dc9f545a32d..1fa783732296 100755 --- a/tools/testing/selftests/vm/run_vmtests.sh +++ b/tools/testing/selftests/vm/run_vmtests.sh @@ -185,4 +185,7 @@ fi run_test ./soft-dirty +# COW tests for anonymous memory +run_test ./anon_cow + exit $exitcode diff --git a/tools/testing/selftests/vm/vm_util.c b/tools/testing/selftests/vm/vm_util.c index f11f8adda521..37dd230673ee 100644 --- a/tools/testing/selftests/vm/vm_util.c +++ b/tools/testing/selftests/vm/vm_util.c @@ -28,6 +28,13 @@ bool pagemap_is_softdirty(int fd, char *start) return entry & 0x0080000000000000ull; } +bool pagemap_is_swapped(int fd, char *start) +{ + uint64_t entry = pagemap_get_entry(fd, start); + + return entry & 0x4000000000000000ull; +} + void clear_softdirty(void) { int ret; diff --git a/tools/testing/selftests/vm/vm_util.h b/tools/testing/selftests/vm/vm_util.h index 5c35de454e08..833df81b2694 100644 --- a/tools/testing/selftests/vm/vm_util.h +++ b/tools/testing/selftests/vm/vm_util.h @@ -4,6 +4,7 @@ uint64_t pagemap_get_entry(int fd, char *start); bool pagemap_is_softdirty(int fd, char *start); +bool pagemap_is_swapped(int fd, char *start); void clear_softdirty(void); bool check_for_pattern(FILE *fp, const char *pattern, char *buf, size_t len); uint64_t read_pmd_pagesize(void); -- cgit v1.2.3 From a905e82ae44b22a25ea73415a3ec1228775eb9a9 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Tue, 27 Sep 2022 13:01:15 +0200 Subject: selftests/vm: factor out pagemap_is_populated() into vm_util We'll reuse it in the anon_cow test next. Link: https://lkml.kernel.org/r/20220927110120.106906-3-david@redhat.com Signed-off-by: David Hildenbrand Cc: Andrea Arcangeli Cc: Christoph von Recklinghausen Cc: Don Dutile Cc: Jason Gunthorpe Cc: John Hubbard Cc: Mike Rapoport Cc: Nadav Amit Cc: Peter Xu Cc: Shuah Khan Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/madv_populate.c | 8 -------- tools/testing/selftests/vm/vm_util.c | 8 ++++++++ tools/testing/selftests/vm/vm_util.h | 1 + 3 files changed, 9 insertions(+), 8 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/vm/madv_populate.c b/tools/testing/selftests/vm/madv_populate.c index 715a42e8e2cd..60547245e479 100644 --- a/tools/testing/selftests/vm/madv_populate.c +++ b/tools/testing/selftests/vm/madv_populate.c @@ -27,14 +27,6 @@ static size_t pagesize; -static bool pagemap_is_populated(int fd, char *start) -{ - uint64_t entry = pagemap_get_entry(fd, start); - - /* Present or swapped. */ - return entry & 0xc000000000000000ull; -} - static void sense_support(void) { char *addr; diff --git a/tools/testing/selftests/vm/vm_util.c b/tools/testing/selftests/vm/vm_util.c index 37dd230673ee..5bbf7641a0f0 100644 --- a/tools/testing/selftests/vm/vm_util.c +++ b/tools/testing/selftests/vm/vm_util.c @@ -35,6 +35,14 @@ bool pagemap_is_swapped(int fd, char *start) return entry & 0x4000000000000000ull; } +bool pagemap_is_populated(int fd, char *start) +{ + uint64_t entry = pagemap_get_entry(fd, start); + + /* Present or swapped. */ + return entry & 0xc000000000000000ull; +} + void clear_softdirty(void) { int ret; diff --git a/tools/testing/selftests/vm/vm_util.h b/tools/testing/selftests/vm/vm_util.h index 833df81b2694..80d5a6ad413b 100644 --- a/tools/testing/selftests/vm/vm_util.h +++ b/tools/testing/selftests/vm/vm_util.h @@ -5,6 +5,7 @@ uint64_t pagemap_get_entry(int fd, char *start); bool pagemap_is_softdirty(int fd, char *start); bool pagemap_is_swapped(int fd, char *start); +bool pagemap_is_populated(int fd, char *start); void clear_softdirty(void); bool check_for_pattern(FILE *fp, const char *pattern, char *buf, size_t len); uint64_t read_pmd_pagesize(void); -- cgit v1.2.3 From f4b5fd6946e244cdedc3bbb9a1f24c8133b2077a Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Tue, 27 Sep 2022 13:01:16 +0200 Subject: selftests/vm: anon_cow: THP tests Let's add various THP variants that we'll run with our existing test cases. Link: https://lkml.kernel.org/r/20220927110120.106906-4-david@redhat.com Signed-off-by: David Hildenbrand Cc: Andrea Arcangeli Cc: Christoph von Recklinghausen Cc: Don Dutile Cc: Jason Gunthorpe Cc: John Hubbard Cc: Mike Rapoport Cc: Nadav Amit Cc: Peter Xu Cc: Shuah Khan Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/anon_cow.c | 259 +++++++++++++++++++++++++++++++++- 1 file changed, 258 insertions(+), 1 deletion(-) (limited to 'tools') diff --git a/tools/testing/selftests/vm/anon_cow.c b/tools/testing/selftests/vm/anon_cow.c index 4613294af758..c1681c9d255f 100644 --- a/tools/testing/selftests/vm/anon_cow.c +++ b/tools/testing/selftests/vm/anon_cow.c @@ -24,6 +24,43 @@ static size_t pagesize; static int pagemap_fd; +static size_t thpsize; + +static void detect_thpsize(void) +{ + int fd = open("/sys/kernel/mm/transparent_hugepage/hpage_pmd_size", + O_RDONLY); + size_t size = 0; + char buf[15]; + int ret; + + if (fd < 0) + return; + + ret = pread(fd, buf, sizeof(buf), 0); + if (ret > 0 && ret < sizeof(buf)) { + buf[ret] = 0; + + size = strtoul(buf, NULL, 10); + if (size < pagesize) + size = 0; + if (size > 0) { + thpsize = size; + ksft_print_msg("[INFO] detected THP size: %zu KiB\n", + thpsize / 1024); + } + } + + close(fd); +} + +static bool range_is_swapped(void *addr, size_t size) +{ + for (; size; addr += pagesize, size -= pagesize) + if (!pagemap_is_swapped(pagemap_fd, addr)) + return false; + return true; +} struct comm_pipes { int child_ready[2]; @@ -319,6 +356,206 @@ static void run_with_base_page_swap(test_fn fn, const char *desc) do_run_with_base_page(fn, true); } +enum thp_run { + THP_RUN_PMD, + THP_RUN_PMD_SWAPOUT, + THP_RUN_PTE, + THP_RUN_PTE_SWAPOUT, + THP_RUN_SINGLE_PTE, + THP_RUN_SINGLE_PTE_SWAPOUT, + THP_RUN_PARTIAL_MREMAP, + THP_RUN_PARTIAL_SHARED, +}; + +static void do_run_with_thp(test_fn fn, enum thp_run thp_run) +{ + char *mem, *mmap_mem, *tmp, *mremap_mem = MAP_FAILED; + size_t size, mmap_size, mremap_size; + int ret; + + /* For alignment purposes, we need twice the thp size. */ + mmap_size = 2 * thpsize; + mmap_mem = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (mmap_mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + return; + } + + /* We need a THP-aligned memory area. */ + mem = (char *)(((uintptr_t)mmap_mem + thpsize) & ~(thpsize - 1)); + + ret = madvise(mem, thpsize, MADV_HUGEPAGE); + if (ret) { + ksft_test_result_fail("MADV_HUGEPAGE failed\n"); + goto munmap; + } + + /* + * Try to populate a THP. Touch the first sub-page and test if we get + * another sub-page populated automatically. + */ + mem[0] = 0; + if (!pagemap_is_populated(pagemap_fd, mem + pagesize)) { + ksft_test_result_skip("Did not get a THP populated\n"); + goto munmap; + } + memset(mem, 0, thpsize); + + size = thpsize; + switch (thp_run) { + case THP_RUN_PMD: + case THP_RUN_PMD_SWAPOUT: + break; + case THP_RUN_PTE: + case THP_RUN_PTE_SWAPOUT: + /* + * Trigger PTE-mapping the THP by temporarily mapping a single + * subpage R/O. + */ + ret = mprotect(mem + pagesize, pagesize, PROT_READ); + if (ret) { + ksft_test_result_fail("mprotect() failed\n"); + goto munmap; + } + ret = mprotect(mem + pagesize, pagesize, PROT_READ | PROT_WRITE); + if (ret) { + ksft_test_result_fail("mprotect() failed\n"); + goto munmap; + } + break; + case THP_RUN_SINGLE_PTE: + case THP_RUN_SINGLE_PTE_SWAPOUT: + /* + * Discard all but a single subpage of that PTE-mapped THP. What + * remains is a single PTE mapping a single subpage. + */ + ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DONTNEED); + if (ret) { + ksft_test_result_fail("MADV_DONTNEED failed\n"); + goto munmap; + } + size = pagesize; + break; + case THP_RUN_PARTIAL_MREMAP: + /* + * Remap half of the THP. We need some new memory location + * for that. + */ + mremap_size = thpsize / 2; + mremap_mem = mmap(NULL, mremap_size, PROT_NONE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + goto munmap; + } + tmp = mremap(mem + mremap_size, mremap_size, mremap_size, + MREMAP_MAYMOVE | MREMAP_FIXED, mremap_mem); + if (tmp != mremap_mem) { + ksft_test_result_fail("mremap() failed\n"); + goto munmap; + } + size = mremap_size; + break; + case THP_RUN_PARTIAL_SHARED: + /* + * Share the first page of the THP with a child and quit the + * child. This will result in some parts of the THP never + * have been shared. + */ + ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DONTFORK); + if (ret) { + ksft_test_result_fail("MADV_DONTFORK failed\n"); + goto munmap; + } + ret = fork(); + if (ret < 0) { + ksft_test_result_fail("fork() failed\n"); + goto munmap; + } else if (!ret) { + exit(0); + } + wait(&ret); + /* Allow for sharing all pages again. */ + ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DOFORK); + if (ret) { + ksft_test_result_fail("MADV_DOFORK failed\n"); + goto munmap; + } + break; + default: + assert(false); + } + + switch (thp_run) { + case THP_RUN_PMD_SWAPOUT: + case THP_RUN_PTE_SWAPOUT: + case THP_RUN_SINGLE_PTE_SWAPOUT: + madvise(mem, size, MADV_PAGEOUT); + if (!range_is_swapped(mem, size)) { + ksft_test_result_skip("MADV_PAGEOUT did not work, is swap enabled?\n"); + goto munmap; + } + break; + default: + break; + } + + fn(mem, size); +munmap: + munmap(mmap_mem, mmap_size); + if (mremap_mem != MAP_FAILED) + munmap(mremap_mem, mremap_size); +} + +static void run_with_thp(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with THP\n", desc); + do_run_with_thp(fn, THP_RUN_PMD); +} + +static void run_with_thp_swap(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with swapped-out THP\n", desc); + do_run_with_thp(fn, THP_RUN_PMD_SWAPOUT); +} + +static void run_with_pte_mapped_thp(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with PTE-mapped THP\n", desc); + do_run_with_thp(fn, THP_RUN_PTE); +} + +static void run_with_pte_mapped_thp_swap(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with swapped-out, PTE-mapped THP\n", desc); + do_run_with_thp(fn, THP_RUN_PTE_SWAPOUT); +} + +static void run_with_single_pte_of_thp(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with single PTE of THP\n", desc); + do_run_with_thp(fn, THP_RUN_SINGLE_PTE); +} + +static void run_with_single_pte_of_thp_swap(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with single PTE of swapped-out THP\n", desc); + do_run_with_thp(fn, THP_RUN_SINGLE_PTE_SWAPOUT); +} + +static void run_with_partial_mremap_thp(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with partially mremap()'ed THP\n", desc); + do_run_with_thp(fn, THP_RUN_PARTIAL_MREMAP); +} + +static void run_with_partial_shared_thp(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with partially shared THP\n", desc); + do_run_with_thp(fn, THP_RUN_PARTIAL_SHARED); +} + struct test_case { const char *desc; test_fn fn; @@ -367,6 +604,16 @@ static void run_test_case(struct test_case const *test_case) { run_with_base_page(test_case->fn, test_case->desc); run_with_base_page_swap(test_case->fn, test_case->desc); + if (thpsize) { + run_with_thp(test_case->fn, test_case->desc); + run_with_thp_swap(test_case->fn, test_case->desc); + run_with_pte_mapped_thp(test_case->fn, test_case->desc); + run_with_pte_mapped_thp_swap(test_case->fn, test_case->desc); + run_with_single_pte_of_thp(test_case->fn, test_case->desc); + run_with_single_pte_of_thp_swap(test_case->fn, test_case->desc); + run_with_partial_mremap_thp(test_case->fn, test_case->desc); + run_with_partial_shared_thp(test_case->fn, test_case->desc); + } } static void run_test_cases(void) @@ -377,15 +624,25 @@ static void run_test_cases(void) run_test_case(&test_cases[i]); } +static int tests_per_test_case(void) +{ + int tests = 2; + + if (thpsize) + tests += 8; + return tests; +} + int main(int argc, char **argv) { int nr_test_cases = ARRAY_SIZE(test_cases); int err; pagesize = getpagesize(); + detect_thpsize(); ksft_print_header(); - ksft_set_plan(nr_test_cases * 2); + ksft_set_plan(nr_test_cases * tests_per_test_case()); pagemap_fd = open("/proc/self/pagemap", O_RDONLY); if (pagemap_fd < 0) -- cgit v1.2.3 From 7dad331be7816103eba8c12caeb88fbd3599c0b9 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Tue, 27 Sep 2022 13:01:17 +0200 Subject: selftests/vm: anon_cow: hugetlb tests Let's run all existing test cases with all hugetlb sizes we're able to detect. Note that some tests cases still fail. This will, for example, be fixed once vmsplice properly uses FOLL_PIN instead of FOLL_GET for pinning. With 2 MiB and 1 GiB hugetlb on x86_64, the expected failures are: # [RUN] vmsplice() + unmap in child ... with hugetlb (2048 kB) not ok 23 No leak from parent into child # [RUN] vmsplice() + unmap in child ... with hugetlb (1048576 kB) not ok 24 No leak from parent into child # [RUN] vmsplice() before fork(), unmap in parent after fork() ... with hugetlb (2048 kB) not ok 35 No leak from child into parent # [RUN] vmsplice() before fork(), unmap in parent after fork() ... with hugetlb (1048576 kB) not ok 36 No leak from child into parent # [RUN] vmsplice() + unmap in parent after fork() ... with hugetlb (2048 kB) not ok 47 No leak from child into parent # [RUN] vmsplice() + unmap in parent after fork() ... with hugetlb (1048576 kB) not ok 48 No leak from child into parent Link: https://lkml.kernel.org/r/20220927110120.106906-5-david@redhat.com Signed-off-by: David Hildenbrand Cc: Andrea Arcangeli Cc: Christoph von Recklinghausen Cc: Don Dutile Cc: Jason Gunthorpe Cc: John Hubbard Cc: Mike Rapoport Cc: Nadav Amit Cc: Peter Xu Cc: Shuah Khan Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/anon_cow.c | 70 ++++++++++++++++++++++++++++++++++- 1 file changed, 69 insertions(+), 1 deletion(-) (limited to 'tools') diff --git a/tools/testing/selftests/vm/anon_cow.c b/tools/testing/selftests/vm/anon_cow.c index c1681c9d255f..78dfdd983380 100644 --- a/tools/testing/selftests/vm/anon_cow.c +++ b/tools/testing/selftests/vm/anon_cow.c @@ -25,6 +25,8 @@ static size_t pagesize; static int pagemap_fd; static size_t thpsize; +static int nr_hugetlbsizes; +static size_t hugetlbsizes[10]; static void detect_thpsize(void) { @@ -54,6 +56,31 @@ static void detect_thpsize(void) close(fd); } +static void detect_hugetlbsizes(void) +{ + DIR *dir = opendir("/sys/kernel/mm/hugepages/"); + + if (!dir) + return; + + while (nr_hugetlbsizes < ARRAY_SIZE(hugetlbsizes)) { + struct dirent *entry = readdir(dir); + size_t kb; + + if (!entry) + break; + if (entry->d_type != DT_DIR) + continue; + if (sscanf(entry->d_name, "hugepages-%zukB", &kb) != 1) + continue; + hugetlbsizes[nr_hugetlbsizes] = kb * 1024; + nr_hugetlbsizes++; + ksft_print_msg("[INFO] detected hugetlb size: %zu KiB\n", + kb); + } + closedir(dir); +} + static bool range_is_swapped(void *addr, size_t size) { for (; size; addr += pagesize, size -= pagesize) @@ -556,6 +583,41 @@ static void run_with_partial_shared_thp(test_fn fn, const char *desc) do_run_with_thp(fn, THP_RUN_PARTIAL_SHARED); } +static void run_with_hugetlb(test_fn fn, const char *desc, size_t hugetlbsize) +{ + int flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB; + char *mem, *dummy; + + ksft_print_msg("[RUN] %s ... with hugetlb (%zu kB)\n", desc, + hugetlbsize / 1024); + + flags |= __builtin_ctzll(hugetlbsize) << MAP_HUGE_SHIFT; + + mem = mmap(NULL, hugetlbsize, PROT_READ | PROT_WRITE, flags, -1, 0); + if (mem == MAP_FAILED) { + ksft_test_result_skip("need more free huge pages\n"); + return; + } + + /* Populate an huge page. */ + memset(mem, 0, hugetlbsize); + + /* + * We need a total of two hugetlb pages to handle COW/unsharing + * properly, otherwise we might get zapped by a SIGBUS. + */ + dummy = mmap(NULL, hugetlbsize, PROT_READ | PROT_WRITE, flags, -1, 0); + if (dummy == MAP_FAILED) { + ksft_test_result_skip("need more free huge pages\n"); + goto munmap; + } + munmap(dummy, hugetlbsize); + + fn(mem, hugetlbsize); +munmap: + munmap(mem, hugetlbsize); +} + struct test_case { const char *desc; test_fn fn; @@ -602,6 +664,8 @@ static const struct test_case test_cases[] = { static void run_test_case(struct test_case const *test_case) { + int i; + run_with_base_page(test_case->fn, test_case->desc); run_with_base_page_swap(test_case->fn, test_case->desc); if (thpsize) { @@ -614,6 +678,9 @@ static void run_test_case(struct test_case const *test_case) run_with_partial_mremap_thp(test_case->fn, test_case->desc); run_with_partial_shared_thp(test_case->fn, test_case->desc); } + for (i = 0; i < nr_hugetlbsizes; i++) + run_with_hugetlb(test_case->fn, test_case->desc, + hugetlbsizes[i]); } static void run_test_cases(void) @@ -626,7 +693,7 @@ static void run_test_cases(void) static int tests_per_test_case(void) { - int tests = 2; + int tests = 2 + nr_hugetlbsizes; if (thpsize) tests += 8; @@ -640,6 +707,7 @@ int main(int argc, char **argv) pagesize = getpagesize(); detect_thpsize(); + detect_hugetlbsizes(); ksft_print_header(); ksft_set_plan(nr_test_cases * tests_per_test_case()); -- cgit v1.2.3 From e487ebbd12986facc7f77129d3ca80de84841170 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Tue, 27 Sep 2022 13:01:18 +0200 Subject: selftests/vm: anon_cow: add liburing test cases io_uring provides a simple mechanism to test long-term, R/W GUP pins -- via fixed buffers -- and can be used to verify that GUP pins stay in sync with the pages in the page table even if a page would temporarily get mapped R/O or concurrent fork() could accidentially end up sharing pinned pages with the child. Note that this essentially re-introduces local_config support that was removed recently in commit 6f83d6c74ea5 ("Kselftests: remove support of libhugetlbfs from kselftests"). [david@redhat.com: s/size_t/ssize_t/ on `cur', `total'.] Link: https://lkml.kernel.org/r/445fe1ae-9e22-0d1d-4d09-272231d2f84a@redhat.com Link: https://lkml.kernel.org/r/20220927110120.106906-6-david@redhat.com Signed-off-by: David Hildenbrand Cc: Andrea Arcangeli Cc: Christoph von Recklinghausen Cc: Don Dutile Cc: Jason Gunthorpe Cc: John Hubbard Cc: Mike Rapoport Cc: Nadav Amit Cc: Peter Xu Cc: Shuah Khan Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/Makefile | 21 +++- tools/testing/selftests/vm/anon_cow.c | 190 +++++++++++++++++++++++++++++ tools/testing/selftests/vm/check_config.sh | 31 +++++ 3 files changed, 241 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/vm/check_config.sh (limited to 'tools') diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index ad07d7a84c3e..00920cb8b499 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -1,7 +1,9 @@ # SPDX-License-Identifier: GPL-2.0 # Makefile for vm selftests -LOCAL_HDRS += $(top_srcdir)/mm/gup_test.h +LOCAL_HDRS += $(selfdir)/vm/local_config.h $(top_srcdir)/mm/gup_test.h + +include local_config.mk uname_M := $(shell uname -m 2>/dev/null || echo not) MACHINE ?= $(shell echo $(uname_M) | sed -e 's/aarch64.*/arm64/' -e 's/ppc64.*/ppc64/') @@ -152,8 +154,25 @@ warn_32bit_failure: endif endif +# ANON_COW_EXTRA_LIBS may get set in local_config.mk, or it may be left empty. +$(OUTPUT)/anon_cow: LDLIBS += $(ANON_COW_EXTRA_LIBS) + $(OUTPUT)/mlock-random-test $(OUTPUT)/memfd_secret: LDLIBS += -lcap $(OUTPUT)/ksm_tests: LDLIBS += -lnuma $(OUTPUT)/migration: LDLIBS += -lnuma + +local_config.mk local_config.h: check_config.sh + /bin/sh ./check_config.sh $(CC) + +EXTRA_CLEAN += local_config.mk local_config.h + +ifeq ($(ANON_COW_EXTRA_LIBS),) +all: warn_missing_liburing + +warn_missing_liburing: + @echo ; \ + echo "Warning: missing liburing support. Some COW tests will be skipped." ; \ + echo +endif diff --git a/tools/testing/selftests/vm/anon_cow.c b/tools/testing/selftests/vm/anon_cow.c index 78dfdd983380..01417a604eda 100644 --- a/tools/testing/selftests/vm/anon_cow.c +++ b/tools/testing/selftests/vm/anon_cow.c @@ -19,6 +19,11 @@ #include #include +#include "local_config.h" +#ifdef LOCAL_CONFIG_HAVE_LIBURING +#include +#endif /* LOCAL_CONFIG_HAVE_LIBURING */ + #include "../kselftest.h" #include "vm_util.h" @@ -334,6 +339,170 @@ static void test_vmsplice_after_fork(char *mem, size_t size) do_test_vmsplice_in_parent(mem, size, false); } +#ifdef LOCAL_CONFIG_HAVE_LIBURING +static void do_test_iouring(char *mem, size_t size, bool use_fork) +{ + struct comm_pipes comm_pipes; + struct io_uring_cqe *cqe; + struct io_uring_sqe *sqe; + struct io_uring ring; + ssize_t cur, total; + struct iovec iov; + char *buf, *tmp; + int ret, fd; + FILE *file; + + ret = setup_comm_pipes(&comm_pipes); + if (ret) { + ksft_test_result_fail("pipe() failed\n"); + return; + } + + file = tmpfile(); + if (!file) { + ksft_test_result_fail("tmpfile() failed\n"); + goto close_comm_pipes; + } + fd = fileno(file); + assert(fd); + + tmp = malloc(size); + if (!tmp) { + ksft_test_result_fail("malloc() failed\n"); + goto close_file; + } + + /* Skip on errors, as we might just lack kernel support. */ + ret = io_uring_queue_init(1, &ring, 0); + if (ret < 0) { + ksft_test_result_skip("io_uring_queue_init() failed\n"); + goto free_tmp; + } + + /* + * Register the range as a fixed buffer. This will FOLL_WRITE | FOLL_PIN + * | FOLL_LONGTERM the range. + * + * Skip on errors, as we might just lack kernel support or might not + * have sufficient MEMLOCK permissions. + */ + iov.iov_base = mem; + iov.iov_len = size; + ret = io_uring_register_buffers(&ring, &iov, 1); + if (ret) { + ksft_test_result_skip("io_uring_register_buffers() failed\n"); + goto queue_exit; + } + + if (use_fork) { + /* + * fork() and keep the child alive until we're done. Note that + * we expect the pinned page to not get shared with the child. + */ + ret = fork(); + if (ret < 0) { + ksft_test_result_fail("fork() failed\n"); + goto unregister_buffers; + } else if (!ret) { + write(comm_pipes.child_ready[1], "0", 1); + while (read(comm_pipes.parent_ready[0], &buf, 1) != 1) + ; + exit(0); + } + + while (read(comm_pipes.child_ready[0], &buf, 1) != 1) + ; + } else { + /* + * Map the page R/O into the page table. Enable softdirty + * tracking to stop the page from getting mapped R/W immediately + * again by mprotect() optimizations. Note that we don't have an + * easy way to test if that worked (the pagemap does not export + * if the page is mapped R/O vs. R/W). + */ + ret = mprotect(mem, size, PROT_READ); + clear_softdirty(); + ret |= mprotect(mem, size, PROT_READ | PROT_WRITE); + if (ret) { + ksft_test_result_fail("mprotect() failed\n"); + goto unregister_buffers; + } + } + + /* + * Modify the page and write page content as observed by the fixed + * buffer pin to the file so we can verify it. + */ + memset(mem, 0xff, size); + sqe = io_uring_get_sqe(&ring); + if (!sqe) { + ksft_test_result_fail("io_uring_get_sqe() failed\n"); + goto quit_child; + } + io_uring_prep_write_fixed(sqe, fd, mem, size, 0, 0); + + ret = io_uring_submit(&ring); + if (ret < 0) { + ksft_test_result_fail("io_uring_submit() failed\n"); + goto quit_child; + } + + ret = io_uring_wait_cqe(&ring, &cqe); + if (ret < 0) { + ksft_test_result_fail("io_uring_wait_cqe() failed\n"); + goto quit_child; + } + + if (cqe->res != size) { + ksft_test_result_fail("write_fixed failed\n"); + goto quit_child; + } + io_uring_cqe_seen(&ring, cqe); + + /* Read back the file content to the temporary buffer. */ + total = 0; + while (total < size) { + cur = pread(fd, tmp + total, size - total, total); + if (cur < 0) { + ksft_test_result_fail("pread() failed\n"); + goto quit_child; + } + total += cur; + } + + /* Finally, check if we read what we expected. */ + ksft_test_result(!memcmp(mem, tmp, size), + "Longterm R/W pin is reliable\n"); + +quit_child: + if (use_fork) { + write(comm_pipes.parent_ready[1], "0", 1); + wait(&ret); + } +unregister_buffers: + io_uring_unregister_buffers(&ring); +queue_exit: + io_uring_queue_exit(&ring); +free_tmp: + free(tmp); +close_file: + fclose(file); +close_comm_pipes: + close_comm_pipes(&comm_pipes); +} + +static void test_iouring_ro(char *mem, size_t size) +{ + do_test_iouring(mem, size, false); +} + +static void test_iouring_fork(char *mem, size_t size) +{ + do_test_iouring(mem, size, true); +} + +#endif /* LOCAL_CONFIG_HAVE_LIBURING */ + typedef void (*test_fn)(char *mem, size_t size); static void do_run_with_base_page(test_fn fn, bool swapout) @@ -660,6 +829,27 @@ static const struct test_case test_cases[] = { "vmsplice() + unmap in parent after fork()", test_vmsplice_after_fork, }, +#ifdef LOCAL_CONFIG_HAVE_LIBURING + /* + * Take a R/W longterm pin and then map the page R/O into the page + * table to trigger a write fault on next access. When modifying the + * page, the page content must be visible via the pin. + */ + { + "R/O-mapping a page registered as iouring fixed buffer", + test_iouring_ro, + }, + /* + * Take a R/W longterm pin and then fork() a child. When modifying the + * page, the page content must be visible via the pin. We expect the + * pinned page to not get shared with the child. + */ + { + "fork() with an iouring fixed buffer", + test_iouring_fork, + }, + +#endif /* LOCAL_CONFIG_HAVE_LIBURING */ }; static void run_test_case(struct test_case const *test_case) diff --git a/tools/testing/selftests/vm/check_config.sh b/tools/testing/selftests/vm/check_config.sh new file mode 100644 index 000000000000..9a44c6520925 --- /dev/null +++ b/tools/testing/selftests/vm/check_config.sh @@ -0,0 +1,31 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# +# Probe for libraries and create header files to record the results. Both C +# header files and Makefile include fragments are created. + +OUTPUT_H_FILE=local_config.h +OUTPUT_MKFILE=local_config.mk + +tmpname=$(mktemp) +tmpfile_c=${tmpname}.c +tmpfile_o=${tmpname}.o + +# liburing +echo "#include " > $tmpfile_c +echo "#include " >> $tmpfile_c +echo "int func(void) { return 0; }" >> $tmpfile_c + +CC=${1:?"Usage: $0 # example compiler: gcc"} +$CC -c $tmpfile_c -o $tmpfile_o >/dev/null 2>&1 + +if [ -f $tmpfile_o ]; then + echo "#define LOCAL_CONFIG_HAVE_LIBURING 1" > $OUTPUT_H_FILE + echo "ANON_COW_EXTRA_LIBS = -luring" > $OUTPUT_MKFILE +else + echo "// No liburing support found" > $OUTPUT_H_FILE + echo "# No liburing support found, so:" > $OUTPUT_MKFILE + echo "ANON_COW_EXTRA_LIBS = " >> $OUTPUT_MKFILE +fi + +rm ${tmpname}.* -- cgit v1.2.3 From 6f1405efc61b6e686bdf6e2e09b41d2d3a5c14e2 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Tue, 27 Sep 2022 13:01:20 +0200 Subject: selftests/vm: anon_cow: add R/O longterm tests via gup_test Let's trigger a R/O longterm pin on three cases of R/O mapped anonymous pages: * exclusive (never shared) * shared (child still alive) * previously shared (child no longer alive) ... and make sure that the pin is reliable: whatever we write via the page tables has to be observable via the pin. Link: https://lkml.kernel.org/r/20220927110120.106906-8-david@redhat.com Signed-off-by: David Hildenbrand Cc: Andrea Arcangeli Cc: Christoph von Recklinghausen Cc: Don Dutile Cc: Jason Gunthorpe Cc: John Hubbard Cc: Mike Rapoport Cc: Nadav Amit Cc: Peter Xu Cc: Shuah Khan Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/anon_cow.c | 210 ++++++++++++++++++++++++++++++++++ 1 file changed, 210 insertions(+) (limited to 'tools') diff --git a/tools/testing/selftests/vm/anon_cow.c b/tools/testing/selftests/vm/anon_cow.c index 01417a604eda..705bd0b3db11 100644 --- a/tools/testing/selftests/vm/anon_cow.c +++ b/tools/testing/selftests/vm/anon_cow.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include "local_config.h" @@ -24,6 +25,7 @@ #include #endif /* LOCAL_CONFIG_HAVE_LIBURING */ +#include "../../../../mm/gup_test.h" #include "../kselftest.h" #include "vm_util.h" @@ -32,6 +34,7 @@ static int pagemap_fd; static size_t thpsize; static int nr_hugetlbsizes; static size_t hugetlbsizes[10]; +static int gup_fd; static void detect_thpsize(void) { @@ -503,6 +506,170 @@ static void test_iouring_fork(char *mem, size_t size) #endif /* LOCAL_CONFIG_HAVE_LIBURING */ +enum ro_pin_test { + RO_PIN_TEST_SHARED, + RO_PIN_TEST_PREVIOUSLY_SHARED, + RO_PIN_TEST_RO_EXCLUSIVE, +}; + +static void do_test_ro_pin(char *mem, size_t size, enum ro_pin_test test, + bool fast) +{ + struct pin_longterm_test args; + struct comm_pipes comm_pipes; + char *tmp, buf; + __u64 tmp_val; + int ret; + + if (gup_fd < 0) { + ksft_test_result_skip("gup_test not available\n"); + return; + } + + tmp = malloc(size); + if (!tmp) { + ksft_test_result_fail("malloc() failed\n"); + return; + } + + ret = setup_comm_pipes(&comm_pipes); + if (ret) { + ksft_test_result_fail("pipe() failed\n"); + goto free_tmp; + } + + switch (test) { + case RO_PIN_TEST_SHARED: + case RO_PIN_TEST_PREVIOUSLY_SHARED: + /* + * Share the pages with our child. As the pages are not pinned, + * this should just work. + */ + ret = fork(); + if (ret < 0) { + ksft_test_result_fail("fork() failed\n"); + goto close_comm_pipes; + } else if (!ret) { + write(comm_pipes.child_ready[1], "0", 1); + while (read(comm_pipes.parent_ready[0], &buf, 1) != 1) + ; + exit(0); + } + + /* Wait until our child is ready. */ + while (read(comm_pipes.child_ready[0], &buf, 1) != 1) + ; + + if (test == RO_PIN_TEST_PREVIOUSLY_SHARED) { + /* + * Tell the child to quit now and wait until it quit. + * The pages should now be mapped R/O into our page + * tables, but they are no longer shared. + */ + write(comm_pipes.parent_ready[1], "0", 1); + wait(&ret); + if (!WIFEXITED(ret)) + ksft_print_msg("[INFO] wait() failed\n"); + } + break; + case RO_PIN_TEST_RO_EXCLUSIVE: + /* + * Map the page R/O into the page table. Enable softdirty + * tracking to stop the page from getting mapped R/W immediately + * again by mprotect() optimizations. Note that we don't have an + * easy way to test if that worked (the pagemap does not export + * if the page is mapped R/O vs. R/W). + */ + ret = mprotect(mem, size, PROT_READ); + clear_softdirty(); + ret |= mprotect(mem, size, PROT_READ | PROT_WRITE); + if (ret) { + ksft_test_result_fail("mprotect() failed\n"); + goto close_comm_pipes; + } + break; + default: + assert(false); + } + + /* Take a R/O pin. This should trigger unsharing. */ + args.addr = (__u64)mem; + args.size = size; + args.flags = fast ? PIN_LONGTERM_TEST_FLAG_USE_FAST : 0; + ret = ioctl(gup_fd, PIN_LONGTERM_TEST_START, &args); + if (ret) { + if (errno == EINVAL) + ksft_test_result_skip("PIN_LONGTERM_TEST_START failed\n"); + else + ksft_test_result_fail("PIN_LONGTERM_TEST_START failed\n"); + goto wait; + } + + /* Modify the page. */ + memset(mem, 0xff, size); + + /* + * Read back the content via the pin to the temporary buffer and + * test if we observed the modification. + */ + tmp_val = (__u64)tmp; + ret = ioctl(gup_fd, PIN_LONGTERM_TEST_READ, &tmp_val); + if (ret) + ksft_test_result_fail("PIN_LONGTERM_TEST_READ failed\n"); + else + ksft_test_result(!memcmp(mem, tmp, size), + "Longterm R/O pin is reliable\n"); + + ret = ioctl(gup_fd, PIN_LONGTERM_TEST_STOP); + if (ret) + ksft_print_msg("[INFO] PIN_LONGTERM_TEST_STOP failed\n"); +wait: + switch (test) { + case RO_PIN_TEST_SHARED: + write(comm_pipes.parent_ready[1], "0", 1); + wait(&ret); + if (!WIFEXITED(ret)) + ksft_print_msg("[INFO] wait() failed\n"); + break; + default: + break; + } +close_comm_pipes: + close_comm_pipes(&comm_pipes); +free_tmp: + free(tmp); +} + +static void test_ro_pin_on_shared(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_SHARED, false); +} + +static void test_ro_fast_pin_on_shared(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_SHARED, true); +} + +static void test_ro_pin_on_ro_previously_shared(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_PREVIOUSLY_SHARED, false); +} + +static void test_ro_fast_pin_on_ro_previously_shared(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_PREVIOUSLY_SHARED, true); +} + +static void test_ro_pin_on_ro_exclusive(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_RO_EXCLUSIVE, false); +} + +static void test_ro_fast_pin_on_ro_exclusive(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_RO_EXCLUSIVE, true); +} + typedef void (*test_fn)(char *mem, size_t size); static void do_run_with_base_page(test_fn fn, bool swapout) @@ -850,6 +1017,48 @@ static const struct test_case test_cases[] = { }, #endif /* LOCAL_CONFIG_HAVE_LIBURING */ + /* + * Take a R/O longterm pin on a R/O-mapped shared anonymous page. + * When modifying the page via the page table, the page content change + * must be visible via the pin. + */ + { + "R/O GUP pin on R/O-mapped shared page", + test_ro_pin_on_shared, + }, + /* Same as above, but using GUP-fast. */ + { + "R/O GUP-fast pin on R/O-mapped shared page", + test_ro_fast_pin_on_shared, + }, + /* + * Take a R/O longterm pin on a R/O-mapped exclusive anonymous page that + * was previously shared. When modifying the page via the page table, + * the page content change must be visible via the pin. + */ + { + "R/O GUP pin on R/O-mapped previously-shared page", + test_ro_pin_on_ro_previously_shared, + }, + /* Same as above, but using GUP-fast. */ + { + "R/O GUP-fast pin on R/O-mapped previously-shared page", + test_ro_fast_pin_on_ro_previously_shared, + }, + /* + * Take a R/O longterm pin on a R/O-mapped exclusive anonymous page. + * When modifying the page via the page table, the page content change + * must be visible via the pin. + */ + { + "R/O GUP pin on R/O-mapped exclusive page", + test_ro_pin_on_ro_exclusive, + }, + /* Same as above, but using GUP-fast. */ + { + "R/O GUP-fast pin on R/O-mapped exclusive page", + test_ro_fast_pin_on_ro_exclusive, + }, }; static void run_test_case(struct test_case const *test_case) @@ -902,6 +1111,7 @@ int main(int argc, char **argv) ksft_print_header(); ksft_set_plan(nr_test_cases * tests_per_test_case()); + gup_fd = open("/sys/kernel/debug/gup_test", O_RDWR); pagemap_fd = open("/proc/self/pagemap", O_RDONLY); if (pagemap_fd < 0) ksft_exit_fail_msg("opening pagemap failed\n"); -- cgit v1.2.3 From 4cc0ee7787d7dc595752a8de2e073efa68f7c965 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Tue, 25 Oct 2022 17:36:48 +0000 Subject: selftests/damon: add tests for DAMON_RECLAIM's enabled parameter Add simple test cases for DAMON_RECLAIM's 'enabled' parameter. Those tests are focusing on the synchronous behavior of DAMON_RECLAIM enabling and disabling. Link: https://lkml.kernel.org/r/20221025173650.90624-3-sj@kernel.org Signed-off-by: SeongJae Park Cc: Shuah Khan Signed-off-by: Andrew Morton --- tools/testing/selftests/damon/Makefile | 1 + tools/testing/selftests/damon/reclaim.sh | 42 ++++++++++++++++++++++++++++++++ 2 files changed, 43 insertions(+) create mode 100644 tools/testing/selftests/damon/reclaim.sh (limited to 'tools') diff --git a/tools/testing/selftests/damon/Makefile b/tools/testing/selftests/damon/Makefile index a1fa2eff8192..dbbf18cb3e6b 100644 --- a/tools/testing/selftests/damon/Makefile +++ b/tools/testing/selftests/damon/Makefile @@ -8,5 +8,6 @@ TEST_PROGS = debugfs_attrs.sh debugfs_schemes.sh debugfs_target_ids.sh TEST_PROGS += debugfs_empty_targets.sh debugfs_huge_count_read_write.sh TEST_PROGS += debugfs_duplicate_context_creation.sh TEST_PROGS += sysfs.sh +TEST_PROGS += reclaim.sh include ../lib.mk diff --git a/tools/testing/selftests/damon/reclaim.sh b/tools/testing/selftests/damon/reclaim.sh new file mode 100644 index 000000000000..78dbc2334cbe --- /dev/null +++ b/tools/testing/selftests/damon/reclaim.sh @@ -0,0 +1,42 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 + +# Kselftest framework requirement - SKIP code is 4. +ksft_skip=4 + +if [ $EUID -ne 0 ] +then + echo "Run as root" + exit $ksft_skip +fi + +damon_reclaim_enabled="/sys/module/damon_reclaim/parameters/enabled" +if [ ! -f "$damon_reclaim_enabled" ] +then + echo "No 'enabled' file. Maybe DAMON_RECLAIM not built" + exit $ksft_skip +fi + +nr_kdamonds=$(pgrep kdamond | wc -l) +if [ "$nr_kdamonds" -ne 0 ] +then + echo "Another kdamond is running" + exit $ksft_skip +fi + +echo Y > "$damon_reclaim_enabled" + +nr_kdamonds=$(pgrep kdamond | wc -l) +if [ "$nr_kdamonds" -ne 1 ] +then + echo "kdamond is not turned on" + exit 1 +fi + +echo N > "$damon_reclaim_enabled" +nr_kdamonds=$(pgrep kdamond | wc -l) +if [ "$nr_kdamonds" -ne 0 ] +then + echo "kdamond is not turned off" + exit 1 +fi -- cgit v1.2.3 From 9cd6ffa60256e931503d347006049b8bef508203 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Tue, 25 Oct 2022 17:36:50 +0000 Subject: selftests/damon: add tests for DAMON_LRU_SORT's enabled parameter Add simple test cases for DAMON_LRU_SORT's 'enabled' parameter. Those tests are focusing on the synchronous behavior of DAMON_RECLAIM enabling and disabling. Link: https://lkml.kernel.org/r/20221025173650.90624-5-sj@kernel.org Signed-off-by: SeongJae Park Cc: Shuah Khan Signed-off-by: Andrew Morton --- tools/testing/selftests/damon/Makefile | 2 +- tools/testing/selftests/damon/lru_sort.sh | 41 +++++++++++++++++++++++++++++++ 2 files changed, 42 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/damon/lru_sort.sh (limited to 'tools') diff --git a/tools/testing/selftests/damon/Makefile b/tools/testing/selftests/damon/Makefile index dbbf18cb3e6b..af490acc5348 100644 --- a/tools/testing/selftests/damon/Makefile +++ b/tools/testing/selftests/damon/Makefile @@ -8,6 +8,6 @@ TEST_PROGS = debugfs_attrs.sh debugfs_schemes.sh debugfs_target_ids.sh TEST_PROGS += debugfs_empty_targets.sh debugfs_huge_count_read_write.sh TEST_PROGS += debugfs_duplicate_context_creation.sh TEST_PROGS += sysfs.sh -TEST_PROGS += reclaim.sh +TEST_PROGS += reclaim.sh lru_sort.sh include ../lib.mk diff --git a/tools/testing/selftests/damon/lru_sort.sh b/tools/testing/selftests/damon/lru_sort.sh new file mode 100644 index 000000000000..61b80197c896 --- /dev/null +++ b/tools/testing/selftests/damon/lru_sort.sh @@ -0,0 +1,41 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 + +# Kselftest framework requirement - SKIP code is 4. +ksft_skip=4 + +if [ $EUID -ne 0 ] +then + echo "Run as root" + exit $ksft_skip +fi + +damon_lru_sort_enabled="/sys/module/damon_lru_sort/parameters/enabled" +if [ ! -f "$damon_lru_sort_enabled" ] +then + echo "No 'enabled' file. Maybe DAMON_LRU_SORT not built" + exit $ksft_skip +fi + +nr_kdamonds=$(pgrep kdamond | wc -l) +if [ "$nr_kdamonds" -ne 0 ] +then + echo "Another kdamond is running" + exit $ksft_skip +fi + +echo Y > "$damon_lru_sort_enabled" +nr_kdamonds=$(pgrep kdamond | wc -l) +if [ "$nr_kdamonds" -ne 1 ] +then + echo "kdamond is not turned on" + exit 1 +fi + +echo N > "$damon_lru_sort_enabled" +nr_kdamonds=$(pgrep kdamond | wc -l) +if [ "$nr_kdamonds" -ne 0 ] +then + echo "kdamond is not turned off" + exit 1 +fi -- cgit v1.2.3 From 2b3ee3f66c673312ea377bcfb54cb2b9abc8473b Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Tue, 1 Nov 2022 22:03:26 +0000 Subject: tools/selftets/damon/sysfs: test tried_regions directory existence Add a simple test case for ensuring tried_regions directory existence. Link: https://lkml.kernel.org/r/20221101220328.95765-7-sj@kernel.org Signed-off-by: SeongJae Park Cc: Jonathan Corbet Cc: Shuah Khan Signed-off-by: Andrew Morton --- tools/testing/selftests/damon/sysfs.sh | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'tools') diff --git a/tools/testing/selftests/damon/sysfs.sh b/tools/testing/selftests/damon/sysfs.sh index 89592c64462f..db4942383a50 100644 --- a/tools/testing/selftests/damon/sysfs.sh +++ b/tools/testing/selftests/damon/sysfs.sh @@ -80,6 +80,12 @@ test_range() ensure_file "$range_dir/max" "exist" 600 } +test_tried_regions() +{ + tried_regions_dir=$1 + ensure_dir "$tried_regions_dir" "exist" +} + test_stats() { stats_dir=$1 @@ -138,6 +144,7 @@ test_scheme() test_quotas "$scheme_dir/quotas" test_watermarks "$scheme_dir/watermarks" test_stats "$scheme_dir/stats" + test_tried_regions "$scheme_dir/tried_regions" } test_schemes() -- cgit v1.2.3 From 634ba645f9bc888227ca954ea643579268d1b6d8 Mon Sep 17 00:00:00 2001 From: Mike Kravetz Date: Thu, 3 Nov 2022 18:16:32 -0700 Subject: selftests/vm: update hugetlb madvise Commit 8ebe0a5eaaeb ("mm,madvise,hugetlb: fix unexpected data loss with MADV_DONTNEED on hugetlbfs") changed how the passed length was interpreted for hugetlb mappings. It was changed from align up to align down. The hugetlb-madvise test explicitly tests this behavior. Change test to expect new behavior. Link: https://lkml.kernel.org/r/20221104011632.357049-1-mike.kravetz@oracle.com Link: https://lore.kernel.org/oe-lkp/202211040619.2ec447d7-oliver.sang@intel.com Signed-off-by: Mike Kravetz Reported-by: kernel test robot Cc: David Hildenbrand Cc: Rik van Riel Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/hugetlb-madvise.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/vm/hugetlb-madvise.c b/tools/testing/selftests/vm/hugetlb-madvise.c index f96435b70986..a634f47d1e56 100644 --- a/tools/testing/selftests/vm/hugetlb-madvise.c +++ b/tools/testing/selftests/vm/hugetlb-madvise.c @@ -195,7 +195,7 @@ int main(int argc, char **argv) exit(1); } - /* addr + length should be aligned up to huge page size */ + /* addr + length should be aligned down to huge page size */ if (madvise(addr, ((NR_HUGE_PAGES - 1) * huge_page_size) + base_page_size, MADV_DONTNEED)) { @@ -203,10 +203,11 @@ int main(int argc, char **argv) exit(1); } - /* should free all pages in mapping */ - validate_free_pages(free_hugepages); + /* should free all but last page in mapping */ + validate_free_pages(free_hugepages - 1); (void)munmap(addr, NR_HUGE_PAGES * huge_page_size); + validate_free_pages(free_hugepages); /* * Test MADV_DONTNEED on anonymous private mapping -- cgit v1.2.3 From d7ec8f421ade2817983963a106b0085cc478c17b Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Mon, 7 Nov 2022 16:50:01 +0000 Subject: selftests/damon: test non-context inputs to rm_contexts file There was a bug[1] that triggered by writing non-context DAMON debugfs file names to the 'rm_contexts' DAMON debugfs file. Add a selftest for the bug to avoid it happen again. [1] https://lore.kernel.org/damon/000000000000ede3ac05ec4abf8e@google.com/ Link: https://lkml.kernel.org/r/20221107165001.5717-3-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton --- tools/testing/selftests/damon/Makefile | 1 + .../selftests/damon/debugfs_rm_non_contexts.sh | 19 +++++++++++++++++++ 2 files changed, 20 insertions(+) create mode 100644 tools/testing/selftests/damon/debugfs_rm_non_contexts.sh (limited to 'tools') diff --git a/tools/testing/selftests/damon/Makefile b/tools/testing/selftests/damon/Makefile index af490acc5348..838a8e49f77b 100644 --- a/tools/testing/selftests/damon/Makefile +++ b/tools/testing/selftests/damon/Makefile @@ -7,6 +7,7 @@ TEST_FILES = _chk_dependency.sh _debugfs_common.sh TEST_PROGS = debugfs_attrs.sh debugfs_schemes.sh debugfs_target_ids.sh TEST_PROGS += debugfs_empty_targets.sh debugfs_huge_count_read_write.sh TEST_PROGS += debugfs_duplicate_context_creation.sh +TEST_PROGS += debugfs_rm_non_contexts.sh TEST_PROGS += sysfs.sh TEST_PROGS += reclaim.sh lru_sort.sh diff --git a/tools/testing/selftests/damon/debugfs_rm_non_contexts.sh b/tools/testing/selftests/damon/debugfs_rm_non_contexts.sh new file mode 100644 index 000000000000..48b7af6b022c --- /dev/null +++ b/tools/testing/selftests/damon/debugfs_rm_non_contexts.sh @@ -0,0 +1,19 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 + +source _debugfs_common.sh + +# Test putting non-ctx files/dirs to rm_contexts file +# =================================================== + +dmesg -C + +for file in "$DBGFS/"* +do + echo "$(basename "$f")" > "$DBGFS/rm_contexts" + if dmesg | grep -q BUG + then + dmesg + exit 1 + fi +done -- cgit v1.2.3 From 1a1af17ea81115914c8efc1177fd94719c84fc11 Mon Sep 17 00:00:00 2001 From: Rong Tao Date: Tue, 8 Nov 2022 19:53:48 +0800 Subject: tools/vm/page_owner: ignore page_owner_sort binary page_owner_sort was introduced since commit 48c96a368579 ("mm/page_owner: keep track of page owners"), and we should ignore it. Link: https://lkml.kernel.org/r/tencent_F6CAC0ABE16839E2B2419BD07316DA65BB06@qq.com Signed-off-by: Rong Tao Signed-off-by: Andrew Morton --- tools/vm/.gitignore | 1 + 1 file changed, 1 insertion(+) (limited to 'tools') diff --git a/tools/vm/.gitignore b/tools/vm/.gitignore index 79bb92ae1bb3..922879f93fc8 100644 --- a/tools/vm/.gitignore +++ b/tools/vm/.gitignore @@ -1,3 +1,4 @@ # SPDX-License-Identifier: GPL-2.0-only slabinfo page-types +page_owner_sort -- cgit v1.2.3 From 07f8bac4982f98fc4b5ae05679d76fccc15079ea Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Tue, 8 Nov 2022 18:46:52 +0100 Subject: selftests/vm: anon_cow: add mprotect() optimization tests Let's extend the test to cover the possible mprotect() optimization when removing write-protection. mprotect() must not allow write-access to a COW-shared page by accident. Link: https://lkml.kernel.org/r/20221108174652.198904-8-david@redhat.com Signed-off-by: David Hildenbrand Cc: Andrea Arcangeli Cc: Anshuman Khandual Cc: Dave Chinner Cc: Hugh Dickins Cc: Linus Torvalds Cc: Mel Gorman Cc: Michael Ellerman Cc: Mike Rapoport Cc: Nadav Amit Cc: Nicholas Piggin Cc: Peter Xu Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/anon_cow.c | 49 ++++++++++++++++++++++++++++++++--- 1 file changed, 46 insertions(+), 3 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/vm/anon_cow.c b/tools/testing/selftests/vm/anon_cow.c index 705bd0b3db11..bbb251eb5025 100644 --- a/tools/testing/selftests/vm/anon_cow.c +++ b/tools/testing/selftests/vm/anon_cow.c @@ -190,7 +190,8 @@ static int child_vmsplice_memcmp_fn(char *mem, size_t size, typedef int (*child_fn)(char *mem, size_t size, struct comm_pipes *comm_pipes); -static void do_test_cow_in_parent(char *mem, size_t size, child_fn fn) +static void do_test_cow_in_parent(char *mem, size_t size, bool do_mprotect, + child_fn fn) { struct comm_pipes comm_pipes; char buf; @@ -212,6 +213,22 @@ static void do_test_cow_in_parent(char *mem, size_t size, child_fn fn) while (read(comm_pipes.child_ready[0], &buf, 1) != 1) ; + + if (do_mprotect) { + /* + * mprotect() optimizations might try avoiding + * write-faults by directly mapping pages writable. + */ + ret = mprotect(mem, size, PROT_READ); + ret |= mprotect(mem, size, PROT_READ|PROT_WRITE); + if (ret) { + ksft_test_result_fail("mprotect() failed\n"); + write(comm_pipes.parent_ready[1], "0", 1); + wait(&ret); + goto close_comm_pipes; + } + } + /* Modify the page. */ memset(mem, 0xff, size); write(comm_pipes.parent_ready[1], "0", 1); @@ -229,12 +246,22 @@ close_comm_pipes: static void test_cow_in_parent(char *mem, size_t size) { - do_test_cow_in_parent(mem, size, child_memcmp_fn); + do_test_cow_in_parent(mem, size, false, child_memcmp_fn); +} + +static void test_cow_in_parent_mprotect(char *mem, size_t size) +{ + do_test_cow_in_parent(mem, size, true, child_memcmp_fn); } static void test_vmsplice_in_child(char *mem, size_t size) { - do_test_cow_in_parent(mem, size, child_vmsplice_memcmp_fn); + do_test_cow_in_parent(mem, size, false, child_vmsplice_memcmp_fn); +} + +static void test_vmsplice_in_child_mprotect(char *mem, size_t size) +{ + do_test_cow_in_parent(mem, size, true, child_vmsplice_memcmp_fn); } static void do_test_vmsplice_in_parent(char *mem, size_t size, @@ -969,6 +996,14 @@ static const struct test_case test_cases[] = { "Basic COW after fork()", test_cow_in_parent, }, + /* + * Basic test, but do an additional mprotect(PROT_READ)+ + * mprotect(PROT_READ|PROT_WRITE) in the parent before write access. + */ + { + "Basic COW after fork() with mprotect() optimization", + test_cow_in_parent_mprotect, + }, /* * vmsplice() [R/O GUP] + unmap in the child; modify in the parent. If * we miss to break COW, the child observes modifications by the parent. @@ -978,6 +1013,14 @@ static const struct test_case test_cases[] = { "vmsplice() + unmap in child", test_vmsplice_in_child }, + /* + * vmsplice() test, but do an additional mprotect(PROT_READ)+ + * mprotect(PROT_READ|PROT_WRITE) in the parent before write access. + */ + { + "vmsplice() + unmap in child with mprotect() optimization", + test_vmsplice_in_child_mprotect + }, /* * vmsplice() [R/O GUP] in parent before fork(), unmap in parent after * fork(); modify in the child. If we miss to break COW, the parent -- cgit v1.2.3 From eff6aa17aa7c06c25c0df80060cd0fe621dac276 Mon Sep 17 00:00:00 2001 From: Rong Tao Date: Sun, 13 Nov 2022 08:38:45 +0800 Subject: selftests/damon: fix unnecessary compilation warnings When testing overflow and overread, there is no need to keep unnecessary compilation warnings, we should simply ignore them. The motivation for this patch is to eliminate the compilation warning, maybe one day we will compile the kernel with "-Werror -Wall", at which point this compilation warning will turn into a compilation error, we should fix this error in advance. How to reproduce the problem (with gcc-11.3.1): $ make -C tools/testing/selftests/ ... warning: `write' reading 4294967295 bytes from a region of size 1 [-Wstringop-overread] warning: `read' writing 4294967295 bytes into a region of size 25 overflows the destination [-Wstringop-overflow=] "-Wno-stringop-overread" is supported at least in gcc-11.1.0. Link: https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=d14c547abd484d3540b692bb8048c4a6efe92c8b Link: https://lkml.kernel.org/r/tencent_51C4ACA8CB3895C2D7F35178440283602107@qq.com Signed-off-by: Rong Tao Reviewed-by: SeongJae Park Signed-off-by: Andrew Morton --- tools/testing/selftests/damon/huge_count_read_write.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'tools') diff --git a/tools/testing/selftests/damon/huge_count_read_write.c b/tools/testing/selftests/damon/huge_count_read_write.c index ad7a6b4cf338..a6fe0689f88d 100644 --- a/tools/testing/selftests/damon/huge_count_read_write.c +++ b/tools/testing/selftests/damon/huge_count_read_write.c @@ -8,6 +8,13 @@ #include #include +#pragma GCC diagnostic push +#if __GNUC__ >= 11 && __GNUC_MINOR__ >= 1 +/* Ignore read(2) overflow and write(2) overread compile warnings */ +#pragma GCC diagnostic ignored "-Wstringop-overread" +#pragma GCC diagnostic ignored "-Wstringop-overflow" +#endif + void write_read_with_huge_count(char *file) { int filedesc = open(file, O_RDWR); @@ -27,6 +34,8 @@ void write_read_with_huge_count(char *file) close(filedesc); } +#pragma GCC diagnostic pop + int main(int argc, char *argv[]) { if (argc != 2) { -- cgit v1.2.3 From 7aca5ca154930a06612f4d7b81f710f3e1027e04 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Wed, 16 Nov 2022 11:26:40 +0100 Subject: selftests/vm: anon_cow: prepare for non-anonymous COW tests Patch series "mm/gup: remove FOLL_FORCE usage from drivers (reliable R/O long-term pinning)". For now, we did not support reliable R/O long-term pinning in COW mappings. That means, if we would trigger R/O long-term pinning in MAP_PRIVATE mapping, we could end up pinning the (R/O-mapped) shared zeropage or a pagecache page. The next write access would trigger a write fault and replace the pinned page by an exclusive anonymous page in the process page table; whatever the process would write to that private page copy would not be visible by the owner of the previous page pin: for example, RDMA could read stale data. The end result is essentially an unexpected and hard-to-debug memory corruption. Some drivers tried working around that limitation by using "FOLL_FORCE|FOLL_WRITE|FOLL_LONGTERM" for R/O long-term pinning for now. FOLL_WRITE would trigger a write fault, if required, and break COW before pinning the page. FOLL_FORCE is required because the VMA might lack write permissions, and drivers wanted to make that working as well, just like one would expect (no write access, but still triggering a write access to break COW). However, that is not a practical solution, because (1) Drivers that don't stick to that undocumented and debatable pattern would still run into that issue. For example, VFIO only uses FOLL_LONGTERM for R/O long-term pinning. (2) Using FOLL_WRITE just to work around a COW mapping + page pinning limitation is unintuitive. FOLL_WRITE would, for example, mark the page softdirty or trigger uffd-wp, even though, there actually isn't going to be any write access. (3) The purpose of FOLL_FORCE is debug access, not access without lack of VMA permissions by arbitrarty drivers. So instead, make R/O long-term pinning work as expected, by breaking COW in a COW mapping early, such that we can remove any FOLL_FORCE usage from drivers and make FOLL_FORCE ptrace-specific (renaming it to FOLL_PTRACE). More details in patch #8. This patch (of 19): Originally, the plan was to have a separate tests for testing COW of non-anonymous (e.g., shared zeropage) pages. Turns out, that we'd need a lot of similar functionality and that there isn't a really good reason to separate it. So let's prepare for non-anon tests by renaming to "cow". Link: https://lkml.kernel.org/r/20221116102659.70287-1-david@redhat.com Link: https://lkml.kernel.org/r/20221116102659.70287-2-david@redhat.com Signed-off-by: David Hildenbrand Acked-by: Vlastimil Babka Cc: Alexander Shishkin Cc: Alexander Viro Cc: Alex Williamson Cc: Andrea Arcangeli Cc: Andy Walls Cc: Anton Ivanov Cc: Arnaldo Carvalho de Melo Cc: Arnd Bergmann Cc: Bernard Metzler Cc: Borislav Petkov Cc: Catalin Marinas Cc: Christian Benvenuti Cc: Christian Gmeiner Cc: Christophe Leroy Cc: Christoph Hellwig Cc: Daniel Vetter Cc: Daniel Vetter Cc: Dave Hansen Cc: David Airlie Cc: David S. Miller Cc: Dennis Dalessandro Cc: "Eric W . Biederman" Cc: Greg Kroah-Hartman Cc: Hans Verkuil Cc: "H. Peter Anvin" Cc: Hugh Dickins Cc: Ingo Molnar Cc: Inki Dae Cc: Ivan Kokshaysky Cc: James Morris Cc: Jason Gunthorpe Cc: Jiri Olsa Cc: Johannes Berg Cc: John Hubbard Cc: Kees Cook Cc: Kentaro Takeda Cc: Krzysztof Kozlowski Cc: Kyungmin Park Cc: Leon Romanovsky Cc: Leon Romanovsky Cc: Linus Torvalds Cc: Lucas Stach Cc: Marek Szyprowski Cc: Mark Rutland Cc: Matthew Wilcox Cc: Matt Turner Cc: Mauro Carvalho Chehab Cc: Michael Ellerman Cc: Mike Kravetz Cc: Muchun Song Cc: Nadav Amit Cc: Namhyung Kim Cc: Nelson Escobar Cc: Nicholas Piggin Cc: Oded Gabbay Cc: Oleg Nesterov Cc: Paul Moore Cc: Peter Xu Cc: Peter Zijlstra Cc: Richard Henderson Cc: Richard Weinberger Cc: Russell King Cc: Serge Hallyn Cc: Seung-Woo Kim Cc: Shuah Khan Cc: Tetsuo Handa Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Tomasz Figa Cc: Will Deacon Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/.gitignore | 2 +- tools/testing/selftests/vm/Makefile | 10 +- tools/testing/selftests/vm/anon_cow.c | 1169 --------------------------- tools/testing/selftests/vm/check_config.sh | 4 +- tools/testing/selftests/vm/cow.c | 1174 ++++++++++++++++++++++++++++ tools/testing/selftests/vm/run_vmtests.sh | 2 +- 6 files changed, 1183 insertions(+), 1178 deletions(-) delete mode 100644 tools/testing/selftests/vm/anon_cow.c create mode 100644 tools/testing/selftests/vm/cow.c (limited to 'tools') diff --git a/tools/testing/selftests/vm/.gitignore b/tools/testing/selftests/vm/.gitignore index 8a536c731e3c..ee8c41c998e6 100644 --- a/tools/testing/selftests/vm/.gitignore +++ b/tools/testing/selftests/vm/.gitignore @@ -1,5 +1,5 @@ # SPDX-License-Identifier: GPL-2.0-only -anon_cow +cow hugepage-mmap hugepage-mremap hugepage-shm diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index 00920cb8b499..a4d764efd6e3 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -27,7 +27,7 @@ MAKEFLAGS += --no-builtin-rules CFLAGS = -Wall -I $(top_srcdir) -I $(top_srcdir)/usr/include $(EXTRA_CFLAGS) $(KHDR_INCLUDES) LDLIBS = -lrt -lpthread -TEST_GEN_FILES = anon_cow +TEST_GEN_FILES = cow TEST_GEN_FILES += compaction_test TEST_GEN_FILES += gup_test TEST_GEN_FILES += hmm-tests @@ -98,7 +98,7 @@ TEST_FILES += va_128TBswitch.sh include ../lib.mk -$(OUTPUT)/anon_cow: vm_util.c +$(OUTPUT)/cow: vm_util.c $(OUTPUT)/khugepaged: vm_util.c $(OUTPUT)/madv_populate: vm_util.c $(OUTPUT)/soft-dirty: vm_util.c @@ -154,8 +154,8 @@ warn_32bit_failure: endif endif -# ANON_COW_EXTRA_LIBS may get set in local_config.mk, or it may be left empty. -$(OUTPUT)/anon_cow: LDLIBS += $(ANON_COW_EXTRA_LIBS) +# cow_EXTRA_LIBS may get set in local_config.mk, or it may be left empty. +$(OUTPUT)/cow: LDLIBS += $(COW_EXTRA_LIBS) $(OUTPUT)/mlock-random-test $(OUTPUT)/memfd_secret: LDLIBS += -lcap @@ -168,7 +168,7 @@ local_config.mk local_config.h: check_config.sh EXTRA_CLEAN += local_config.mk local_config.h -ifeq ($(ANON_COW_EXTRA_LIBS),) +ifeq ($(COW_EXTRA_LIBS),) all: warn_missing_liburing warn_missing_liburing: diff --git a/tools/testing/selftests/vm/anon_cow.c b/tools/testing/selftests/vm/anon_cow.c deleted file mode 100644 index bbb251eb5025..000000000000 --- a/tools/testing/selftests/vm/anon_cow.c +++ /dev/null @@ -1,1169 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * COW (Copy On Write) tests for anonymous memory. - * - * Copyright 2022, Red Hat, Inc. - * - * Author(s): David Hildenbrand - */ -#define _GNU_SOURCE -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include "local_config.h" -#ifdef LOCAL_CONFIG_HAVE_LIBURING -#include -#endif /* LOCAL_CONFIG_HAVE_LIBURING */ - -#include "../../../../mm/gup_test.h" -#include "../kselftest.h" -#include "vm_util.h" - -static size_t pagesize; -static int pagemap_fd; -static size_t thpsize; -static int nr_hugetlbsizes; -static size_t hugetlbsizes[10]; -static int gup_fd; - -static void detect_thpsize(void) -{ - int fd = open("/sys/kernel/mm/transparent_hugepage/hpage_pmd_size", - O_RDONLY); - size_t size = 0; - char buf[15]; - int ret; - - if (fd < 0) - return; - - ret = pread(fd, buf, sizeof(buf), 0); - if (ret > 0 && ret < sizeof(buf)) { - buf[ret] = 0; - - size = strtoul(buf, NULL, 10); - if (size < pagesize) - size = 0; - if (size > 0) { - thpsize = size; - ksft_print_msg("[INFO] detected THP size: %zu KiB\n", - thpsize / 1024); - } - } - - close(fd); -} - -static void detect_hugetlbsizes(void) -{ - DIR *dir = opendir("/sys/kernel/mm/hugepages/"); - - if (!dir) - return; - - while (nr_hugetlbsizes < ARRAY_SIZE(hugetlbsizes)) { - struct dirent *entry = readdir(dir); - size_t kb; - - if (!entry) - break; - if (entry->d_type != DT_DIR) - continue; - if (sscanf(entry->d_name, "hugepages-%zukB", &kb) != 1) - continue; - hugetlbsizes[nr_hugetlbsizes] = kb * 1024; - nr_hugetlbsizes++; - ksft_print_msg("[INFO] detected hugetlb size: %zu KiB\n", - kb); - } - closedir(dir); -} - -static bool range_is_swapped(void *addr, size_t size) -{ - for (; size; addr += pagesize, size -= pagesize) - if (!pagemap_is_swapped(pagemap_fd, addr)) - return false; - return true; -} - -struct comm_pipes { - int child_ready[2]; - int parent_ready[2]; -}; - -static int setup_comm_pipes(struct comm_pipes *comm_pipes) -{ - if (pipe(comm_pipes->child_ready) < 0) - return -errno; - if (pipe(comm_pipes->parent_ready) < 0) { - close(comm_pipes->child_ready[0]); - close(comm_pipes->child_ready[1]); - return -errno; - } - - return 0; -} - -static void close_comm_pipes(struct comm_pipes *comm_pipes) -{ - close(comm_pipes->child_ready[0]); - close(comm_pipes->child_ready[1]); - close(comm_pipes->parent_ready[0]); - close(comm_pipes->parent_ready[1]); -} - -static int child_memcmp_fn(char *mem, size_t size, - struct comm_pipes *comm_pipes) -{ - char *old = malloc(size); - char buf; - - /* Backup the original content. */ - memcpy(old, mem, size); - - /* Wait until the parent modified the page. */ - write(comm_pipes->child_ready[1], "0", 1); - while (read(comm_pipes->parent_ready[0], &buf, 1) != 1) - ; - - /* See if we still read the old values. */ - return memcmp(old, mem, size); -} - -static int child_vmsplice_memcmp_fn(char *mem, size_t size, - struct comm_pipes *comm_pipes) -{ - struct iovec iov = { - .iov_base = mem, - .iov_len = size, - }; - ssize_t cur, total, transferred; - char *old, *new; - int fds[2]; - char buf; - - old = malloc(size); - new = malloc(size); - - /* Backup the original content. */ - memcpy(old, mem, size); - - if (pipe(fds) < 0) - return -errno; - - /* Trigger a read-only pin. */ - transferred = vmsplice(fds[1], &iov, 1, 0); - if (transferred < 0) - return -errno; - if (transferred == 0) - return -EINVAL; - - /* Unmap it from our page tables. */ - if (munmap(mem, size) < 0) - return -errno; - - /* Wait until the parent modified it. */ - write(comm_pipes->child_ready[1], "0", 1); - while (read(comm_pipes->parent_ready[0], &buf, 1) != 1) - ; - - /* See if we still read the old values via the pipe. */ - for (total = 0; total < transferred; total += cur) { - cur = read(fds[0], new + total, transferred - total); - if (cur < 0) - return -errno; - } - - return memcmp(old, new, transferred); -} - -typedef int (*child_fn)(char *mem, size_t size, struct comm_pipes *comm_pipes); - -static void do_test_cow_in_parent(char *mem, size_t size, bool do_mprotect, - child_fn fn) -{ - struct comm_pipes comm_pipes; - char buf; - int ret; - - ret = setup_comm_pipes(&comm_pipes); - if (ret) { - ksft_test_result_fail("pipe() failed\n"); - return; - } - - ret = fork(); - if (ret < 0) { - ksft_test_result_fail("fork() failed\n"); - goto close_comm_pipes; - } else if (!ret) { - exit(fn(mem, size, &comm_pipes)); - } - - while (read(comm_pipes.child_ready[0], &buf, 1) != 1) - ; - - if (do_mprotect) { - /* - * mprotect() optimizations might try avoiding - * write-faults by directly mapping pages writable. - */ - ret = mprotect(mem, size, PROT_READ); - ret |= mprotect(mem, size, PROT_READ|PROT_WRITE); - if (ret) { - ksft_test_result_fail("mprotect() failed\n"); - write(comm_pipes.parent_ready[1], "0", 1); - wait(&ret); - goto close_comm_pipes; - } - } - - /* Modify the page. */ - memset(mem, 0xff, size); - write(comm_pipes.parent_ready[1], "0", 1); - - wait(&ret); - if (WIFEXITED(ret)) - ret = WEXITSTATUS(ret); - else - ret = -EINVAL; - - ksft_test_result(!ret, "No leak from parent into child\n"); -close_comm_pipes: - close_comm_pipes(&comm_pipes); -} - -static void test_cow_in_parent(char *mem, size_t size) -{ - do_test_cow_in_parent(mem, size, false, child_memcmp_fn); -} - -static void test_cow_in_parent_mprotect(char *mem, size_t size) -{ - do_test_cow_in_parent(mem, size, true, child_memcmp_fn); -} - -static void test_vmsplice_in_child(char *mem, size_t size) -{ - do_test_cow_in_parent(mem, size, false, child_vmsplice_memcmp_fn); -} - -static void test_vmsplice_in_child_mprotect(char *mem, size_t size) -{ - do_test_cow_in_parent(mem, size, true, child_vmsplice_memcmp_fn); -} - -static void do_test_vmsplice_in_parent(char *mem, size_t size, - bool before_fork) -{ - struct iovec iov = { - .iov_base = mem, - .iov_len = size, - }; - ssize_t cur, total, transferred; - struct comm_pipes comm_pipes; - char *old, *new; - int ret, fds[2]; - char buf; - - old = malloc(size); - new = malloc(size); - - memcpy(old, mem, size); - - ret = setup_comm_pipes(&comm_pipes); - if (ret) { - ksft_test_result_fail("pipe() failed\n"); - goto free; - } - - if (pipe(fds) < 0) { - ksft_test_result_fail("pipe() failed\n"); - goto close_comm_pipes; - } - - if (before_fork) { - transferred = vmsplice(fds[1], &iov, 1, 0); - if (transferred <= 0) { - ksft_test_result_fail("vmsplice() failed\n"); - goto close_pipe; - } - } - - ret = fork(); - if (ret < 0) { - ksft_test_result_fail("fork() failed\n"); - goto close_pipe; - } else if (!ret) { - write(comm_pipes.child_ready[1], "0", 1); - while (read(comm_pipes.parent_ready[0], &buf, 1) != 1) - ; - /* Modify page content in the child. */ - memset(mem, 0xff, size); - exit(0); - } - - if (!before_fork) { - transferred = vmsplice(fds[1], &iov, 1, 0); - if (transferred <= 0) { - ksft_test_result_fail("vmsplice() failed\n"); - wait(&ret); - goto close_pipe; - } - } - - while (read(comm_pipes.child_ready[0], &buf, 1) != 1) - ; - if (munmap(mem, size) < 0) { - ksft_test_result_fail("munmap() failed\n"); - goto close_pipe; - } - write(comm_pipes.parent_ready[1], "0", 1); - - /* Wait until the child is done writing. */ - wait(&ret); - if (!WIFEXITED(ret)) { - ksft_test_result_fail("wait() failed\n"); - goto close_pipe; - } - - /* See if we still read the old values. */ - for (total = 0; total < transferred; total += cur) { - cur = read(fds[0], new + total, transferred - total); - if (cur < 0) { - ksft_test_result_fail("read() failed\n"); - goto close_pipe; - } - } - - ksft_test_result(!memcmp(old, new, transferred), - "No leak from child into parent\n"); -close_pipe: - close(fds[0]); - close(fds[1]); -close_comm_pipes: - close_comm_pipes(&comm_pipes); -free: - free(old); - free(new); -} - -static void test_vmsplice_before_fork(char *mem, size_t size) -{ - do_test_vmsplice_in_parent(mem, size, true); -} - -static void test_vmsplice_after_fork(char *mem, size_t size) -{ - do_test_vmsplice_in_parent(mem, size, false); -} - -#ifdef LOCAL_CONFIG_HAVE_LIBURING -static void do_test_iouring(char *mem, size_t size, bool use_fork) -{ - struct comm_pipes comm_pipes; - struct io_uring_cqe *cqe; - struct io_uring_sqe *sqe; - struct io_uring ring; - ssize_t cur, total; - struct iovec iov; - char *buf, *tmp; - int ret, fd; - FILE *file; - - ret = setup_comm_pipes(&comm_pipes); - if (ret) { - ksft_test_result_fail("pipe() failed\n"); - return; - } - - file = tmpfile(); - if (!file) { - ksft_test_result_fail("tmpfile() failed\n"); - goto close_comm_pipes; - } - fd = fileno(file); - assert(fd); - - tmp = malloc(size); - if (!tmp) { - ksft_test_result_fail("malloc() failed\n"); - goto close_file; - } - - /* Skip on errors, as we might just lack kernel support. */ - ret = io_uring_queue_init(1, &ring, 0); - if (ret < 0) { - ksft_test_result_skip("io_uring_queue_init() failed\n"); - goto free_tmp; - } - - /* - * Register the range as a fixed buffer. This will FOLL_WRITE | FOLL_PIN - * | FOLL_LONGTERM the range. - * - * Skip on errors, as we might just lack kernel support or might not - * have sufficient MEMLOCK permissions. - */ - iov.iov_base = mem; - iov.iov_len = size; - ret = io_uring_register_buffers(&ring, &iov, 1); - if (ret) { - ksft_test_result_skip("io_uring_register_buffers() failed\n"); - goto queue_exit; - } - - if (use_fork) { - /* - * fork() and keep the child alive until we're done. Note that - * we expect the pinned page to not get shared with the child. - */ - ret = fork(); - if (ret < 0) { - ksft_test_result_fail("fork() failed\n"); - goto unregister_buffers; - } else if (!ret) { - write(comm_pipes.child_ready[1], "0", 1); - while (read(comm_pipes.parent_ready[0], &buf, 1) != 1) - ; - exit(0); - } - - while (read(comm_pipes.child_ready[0], &buf, 1) != 1) - ; - } else { - /* - * Map the page R/O into the page table. Enable softdirty - * tracking to stop the page from getting mapped R/W immediately - * again by mprotect() optimizations. Note that we don't have an - * easy way to test if that worked (the pagemap does not export - * if the page is mapped R/O vs. R/W). - */ - ret = mprotect(mem, size, PROT_READ); - clear_softdirty(); - ret |= mprotect(mem, size, PROT_READ | PROT_WRITE); - if (ret) { - ksft_test_result_fail("mprotect() failed\n"); - goto unregister_buffers; - } - } - - /* - * Modify the page and write page content as observed by the fixed - * buffer pin to the file so we can verify it. - */ - memset(mem, 0xff, size); - sqe = io_uring_get_sqe(&ring); - if (!sqe) { - ksft_test_result_fail("io_uring_get_sqe() failed\n"); - goto quit_child; - } - io_uring_prep_write_fixed(sqe, fd, mem, size, 0, 0); - - ret = io_uring_submit(&ring); - if (ret < 0) { - ksft_test_result_fail("io_uring_submit() failed\n"); - goto quit_child; - } - - ret = io_uring_wait_cqe(&ring, &cqe); - if (ret < 0) { - ksft_test_result_fail("io_uring_wait_cqe() failed\n"); - goto quit_child; - } - - if (cqe->res != size) { - ksft_test_result_fail("write_fixed failed\n"); - goto quit_child; - } - io_uring_cqe_seen(&ring, cqe); - - /* Read back the file content to the temporary buffer. */ - total = 0; - while (total < size) { - cur = pread(fd, tmp + total, size - total, total); - if (cur < 0) { - ksft_test_result_fail("pread() failed\n"); - goto quit_child; - } - total += cur; - } - - /* Finally, check if we read what we expected. */ - ksft_test_result(!memcmp(mem, tmp, size), - "Longterm R/W pin is reliable\n"); - -quit_child: - if (use_fork) { - write(comm_pipes.parent_ready[1], "0", 1); - wait(&ret); - } -unregister_buffers: - io_uring_unregister_buffers(&ring); -queue_exit: - io_uring_queue_exit(&ring); -free_tmp: - free(tmp); -close_file: - fclose(file); -close_comm_pipes: - close_comm_pipes(&comm_pipes); -} - -static void test_iouring_ro(char *mem, size_t size) -{ - do_test_iouring(mem, size, false); -} - -static void test_iouring_fork(char *mem, size_t size) -{ - do_test_iouring(mem, size, true); -} - -#endif /* LOCAL_CONFIG_HAVE_LIBURING */ - -enum ro_pin_test { - RO_PIN_TEST_SHARED, - RO_PIN_TEST_PREVIOUSLY_SHARED, - RO_PIN_TEST_RO_EXCLUSIVE, -}; - -static void do_test_ro_pin(char *mem, size_t size, enum ro_pin_test test, - bool fast) -{ - struct pin_longterm_test args; - struct comm_pipes comm_pipes; - char *tmp, buf; - __u64 tmp_val; - int ret; - - if (gup_fd < 0) { - ksft_test_result_skip("gup_test not available\n"); - return; - } - - tmp = malloc(size); - if (!tmp) { - ksft_test_result_fail("malloc() failed\n"); - return; - } - - ret = setup_comm_pipes(&comm_pipes); - if (ret) { - ksft_test_result_fail("pipe() failed\n"); - goto free_tmp; - } - - switch (test) { - case RO_PIN_TEST_SHARED: - case RO_PIN_TEST_PREVIOUSLY_SHARED: - /* - * Share the pages with our child. As the pages are not pinned, - * this should just work. - */ - ret = fork(); - if (ret < 0) { - ksft_test_result_fail("fork() failed\n"); - goto close_comm_pipes; - } else if (!ret) { - write(comm_pipes.child_ready[1], "0", 1); - while (read(comm_pipes.parent_ready[0], &buf, 1) != 1) - ; - exit(0); - } - - /* Wait until our child is ready. */ - while (read(comm_pipes.child_ready[0], &buf, 1) != 1) - ; - - if (test == RO_PIN_TEST_PREVIOUSLY_SHARED) { - /* - * Tell the child to quit now and wait until it quit. - * The pages should now be mapped R/O into our page - * tables, but they are no longer shared. - */ - write(comm_pipes.parent_ready[1], "0", 1); - wait(&ret); - if (!WIFEXITED(ret)) - ksft_print_msg("[INFO] wait() failed\n"); - } - break; - case RO_PIN_TEST_RO_EXCLUSIVE: - /* - * Map the page R/O into the page table. Enable softdirty - * tracking to stop the page from getting mapped R/W immediately - * again by mprotect() optimizations. Note that we don't have an - * easy way to test if that worked (the pagemap does not export - * if the page is mapped R/O vs. R/W). - */ - ret = mprotect(mem, size, PROT_READ); - clear_softdirty(); - ret |= mprotect(mem, size, PROT_READ | PROT_WRITE); - if (ret) { - ksft_test_result_fail("mprotect() failed\n"); - goto close_comm_pipes; - } - break; - default: - assert(false); - } - - /* Take a R/O pin. This should trigger unsharing. */ - args.addr = (__u64)mem; - args.size = size; - args.flags = fast ? PIN_LONGTERM_TEST_FLAG_USE_FAST : 0; - ret = ioctl(gup_fd, PIN_LONGTERM_TEST_START, &args); - if (ret) { - if (errno == EINVAL) - ksft_test_result_skip("PIN_LONGTERM_TEST_START failed\n"); - else - ksft_test_result_fail("PIN_LONGTERM_TEST_START failed\n"); - goto wait; - } - - /* Modify the page. */ - memset(mem, 0xff, size); - - /* - * Read back the content via the pin to the temporary buffer and - * test if we observed the modification. - */ - tmp_val = (__u64)tmp; - ret = ioctl(gup_fd, PIN_LONGTERM_TEST_READ, &tmp_val); - if (ret) - ksft_test_result_fail("PIN_LONGTERM_TEST_READ failed\n"); - else - ksft_test_result(!memcmp(mem, tmp, size), - "Longterm R/O pin is reliable\n"); - - ret = ioctl(gup_fd, PIN_LONGTERM_TEST_STOP); - if (ret) - ksft_print_msg("[INFO] PIN_LONGTERM_TEST_STOP failed\n"); -wait: - switch (test) { - case RO_PIN_TEST_SHARED: - write(comm_pipes.parent_ready[1], "0", 1); - wait(&ret); - if (!WIFEXITED(ret)) - ksft_print_msg("[INFO] wait() failed\n"); - break; - default: - break; - } -close_comm_pipes: - close_comm_pipes(&comm_pipes); -free_tmp: - free(tmp); -} - -static void test_ro_pin_on_shared(char *mem, size_t size) -{ - do_test_ro_pin(mem, size, RO_PIN_TEST_SHARED, false); -} - -static void test_ro_fast_pin_on_shared(char *mem, size_t size) -{ - do_test_ro_pin(mem, size, RO_PIN_TEST_SHARED, true); -} - -static void test_ro_pin_on_ro_previously_shared(char *mem, size_t size) -{ - do_test_ro_pin(mem, size, RO_PIN_TEST_PREVIOUSLY_SHARED, false); -} - -static void test_ro_fast_pin_on_ro_previously_shared(char *mem, size_t size) -{ - do_test_ro_pin(mem, size, RO_PIN_TEST_PREVIOUSLY_SHARED, true); -} - -static void test_ro_pin_on_ro_exclusive(char *mem, size_t size) -{ - do_test_ro_pin(mem, size, RO_PIN_TEST_RO_EXCLUSIVE, false); -} - -static void test_ro_fast_pin_on_ro_exclusive(char *mem, size_t size) -{ - do_test_ro_pin(mem, size, RO_PIN_TEST_RO_EXCLUSIVE, true); -} - -typedef void (*test_fn)(char *mem, size_t size); - -static void do_run_with_base_page(test_fn fn, bool swapout) -{ - char *mem; - int ret; - - mem = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, - MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); - if (mem == MAP_FAILED) { - ksft_test_result_fail("mmap() failed\n"); - return; - } - - ret = madvise(mem, pagesize, MADV_NOHUGEPAGE); - /* Ignore if not around on a kernel. */ - if (ret && errno != EINVAL) { - ksft_test_result_fail("MADV_NOHUGEPAGE failed\n"); - goto munmap; - } - - /* Populate a base page. */ - memset(mem, 0, pagesize); - - if (swapout) { - madvise(mem, pagesize, MADV_PAGEOUT); - if (!pagemap_is_swapped(pagemap_fd, mem)) { - ksft_test_result_skip("MADV_PAGEOUT did not work, is swap enabled?\n"); - goto munmap; - } - } - - fn(mem, pagesize); -munmap: - munmap(mem, pagesize); -} - -static void run_with_base_page(test_fn fn, const char *desc) -{ - ksft_print_msg("[RUN] %s ... with base page\n", desc); - do_run_with_base_page(fn, false); -} - -static void run_with_base_page_swap(test_fn fn, const char *desc) -{ - ksft_print_msg("[RUN] %s ... with swapped out base page\n", desc); - do_run_with_base_page(fn, true); -} - -enum thp_run { - THP_RUN_PMD, - THP_RUN_PMD_SWAPOUT, - THP_RUN_PTE, - THP_RUN_PTE_SWAPOUT, - THP_RUN_SINGLE_PTE, - THP_RUN_SINGLE_PTE_SWAPOUT, - THP_RUN_PARTIAL_MREMAP, - THP_RUN_PARTIAL_SHARED, -}; - -static void do_run_with_thp(test_fn fn, enum thp_run thp_run) -{ - char *mem, *mmap_mem, *tmp, *mremap_mem = MAP_FAILED; - size_t size, mmap_size, mremap_size; - int ret; - - /* For alignment purposes, we need twice the thp size. */ - mmap_size = 2 * thpsize; - mmap_mem = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, - MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); - if (mmap_mem == MAP_FAILED) { - ksft_test_result_fail("mmap() failed\n"); - return; - } - - /* We need a THP-aligned memory area. */ - mem = (char *)(((uintptr_t)mmap_mem + thpsize) & ~(thpsize - 1)); - - ret = madvise(mem, thpsize, MADV_HUGEPAGE); - if (ret) { - ksft_test_result_fail("MADV_HUGEPAGE failed\n"); - goto munmap; - } - - /* - * Try to populate a THP. Touch the first sub-page and test if we get - * another sub-page populated automatically. - */ - mem[0] = 0; - if (!pagemap_is_populated(pagemap_fd, mem + pagesize)) { - ksft_test_result_skip("Did not get a THP populated\n"); - goto munmap; - } - memset(mem, 0, thpsize); - - size = thpsize; - switch (thp_run) { - case THP_RUN_PMD: - case THP_RUN_PMD_SWAPOUT: - break; - case THP_RUN_PTE: - case THP_RUN_PTE_SWAPOUT: - /* - * Trigger PTE-mapping the THP by temporarily mapping a single - * subpage R/O. - */ - ret = mprotect(mem + pagesize, pagesize, PROT_READ); - if (ret) { - ksft_test_result_fail("mprotect() failed\n"); - goto munmap; - } - ret = mprotect(mem + pagesize, pagesize, PROT_READ | PROT_WRITE); - if (ret) { - ksft_test_result_fail("mprotect() failed\n"); - goto munmap; - } - break; - case THP_RUN_SINGLE_PTE: - case THP_RUN_SINGLE_PTE_SWAPOUT: - /* - * Discard all but a single subpage of that PTE-mapped THP. What - * remains is a single PTE mapping a single subpage. - */ - ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DONTNEED); - if (ret) { - ksft_test_result_fail("MADV_DONTNEED failed\n"); - goto munmap; - } - size = pagesize; - break; - case THP_RUN_PARTIAL_MREMAP: - /* - * Remap half of the THP. We need some new memory location - * for that. - */ - mremap_size = thpsize / 2; - mremap_mem = mmap(NULL, mremap_size, PROT_NONE, - MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); - if (mem == MAP_FAILED) { - ksft_test_result_fail("mmap() failed\n"); - goto munmap; - } - tmp = mremap(mem + mremap_size, mremap_size, mremap_size, - MREMAP_MAYMOVE | MREMAP_FIXED, mremap_mem); - if (tmp != mremap_mem) { - ksft_test_result_fail("mremap() failed\n"); - goto munmap; - } - size = mremap_size; - break; - case THP_RUN_PARTIAL_SHARED: - /* - * Share the first page of the THP with a child and quit the - * child. This will result in some parts of the THP never - * have been shared. - */ - ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DONTFORK); - if (ret) { - ksft_test_result_fail("MADV_DONTFORK failed\n"); - goto munmap; - } - ret = fork(); - if (ret < 0) { - ksft_test_result_fail("fork() failed\n"); - goto munmap; - } else if (!ret) { - exit(0); - } - wait(&ret); - /* Allow for sharing all pages again. */ - ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DOFORK); - if (ret) { - ksft_test_result_fail("MADV_DOFORK failed\n"); - goto munmap; - } - break; - default: - assert(false); - } - - switch (thp_run) { - case THP_RUN_PMD_SWAPOUT: - case THP_RUN_PTE_SWAPOUT: - case THP_RUN_SINGLE_PTE_SWAPOUT: - madvise(mem, size, MADV_PAGEOUT); - if (!range_is_swapped(mem, size)) { - ksft_test_result_skip("MADV_PAGEOUT did not work, is swap enabled?\n"); - goto munmap; - } - break; - default: - break; - } - - fn(mem, size); -munmap: - munmap(mmap_mem, mmap_size); - if (mremap_mem != MAP_FAILED) - munmap(mremap_mem, mremap_size); -} - -static void run_with_thp(test_fn fn, const char *desc) -{ - ksft_print_msg("[RUN] %s ... with THP\n", desc); - do_run_with_thp(fn, THP_RUN_PMD); -} - -static void run_with_thp_swap(test_fn fn, const char *desc) -{ - ksft_print_msg("[RUN] %s ... with swapped-out THP\n", desc); - do_run_with_thp(fn, THP_RUN_PMD_SWAPOUT); -} - -static void run_with_pte_mapped_thp(test_fn fn, const char *desc) -{ - ksft_print_msg("[RUN] %s ... with PTE-mapped THP\n", desc); - do_run_with_thp(fn, THP_RUN_PTE); -} - -static void run_with_pte_mapped_thp_swap(test_fn fn, const char *desc) -{ - ksft_print_msg("[RUN] %s ... with swapped-out, PTE-mapped THP\n", desc); - do_run_with_thp(fn, THP_RUN_PTE_SWAPOUT); -} - -static void run_with_single_pte_of_thp(test_fn fn, const char *desc) -{ - ksft_print_msg("[RUN] %s ... with single PTE of THP\n", desc); - do_run_with_thp(fn, THP_RUN_SINGLE_PTE); -} - -static void run_with_single_pte_of_thp_swap(test_fn fn, const char *desc) -{ - ksft_print_msg("[RUN] %s ... with single PTE of swapped-out THP\n", desc); - do_run_with_thp(fn, THP_RUN_SINGLE_PTE_SWAPOUT); -} - -static void run_with_partial_mremap_thp(test_fn fn, const char *desc) -{ - ksft_print_msg("[RUN] %s ... with partially mremap()'ed THP\n", desc); - do_run_with_thp(fn, THP_RUN_PARTIAL_MREMAP); -} - -static void run_with_partial_shared_thp(test_fn fn, const char *desc) -{ - ksft_print_msg("[RUN] %s ... with partially shared THP\n", desc); - do_run_with_thp(fn, THP_RUN_PARTIAL_SHARED); -} - -static void run_with_hugetlb(test_fn fn, const char *desc, size_t hugetlbsize) -{ - int flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB; - char *mem, *dummy; - - ksft_print_msg("[RUN] %s ... with hugetlb (%zu kB)\n", desc, - hugetlbsize / 1024); - - flags |= __builtin_ctzll(hugetlbsize) << MAP_HUGE_SHIFT; - - mem = mmap(NULL, hugetlbsize, PROT_READ | PROT_WRITE, flags, -1, 0); - if (mem == MAP_FAILED) { - ksft_test_result_skip("need more free huge pages\n"); - return; - } - - /* Populate an huge page. */ - memset(mem, 0, hugetlbsize); - - /* - * We need a total of two hugetlb pages to handle COW/unsharing - * properly, otherwise we might get zapped by a SIGBUS. - */ - dummy = mmap(NULL, hugetlbsize, PROT_READ | PROT_WRITE, flags, -1, 0); - if (dummy == MAP_FAILED) { - ksft_test_result_skip("need more free huge pages\n"); - goto munmap; - } - munmap(dummy, hugetlbsize); - - fn(mem, hugetlbsize); -munmap: - munmap(mem, hugetlbsize); -} - -struct test_case { - const char *desc; - test_fn fn; -}; - -static const struct test_case test_cases[] = { - /* - * Basic COW tests for fork() without any GUP. If we miss to break COW, - * either the child can observe modifications by the parent or the - * other way around. - */ - { - "Basic COW after fork()", - test_cow_in_parent, - }, - /* - * Basic test, but do an additional mprotect(PROT_READ)+ - * mprotect(PROT_READ|PROT_WRITE) in the parent before write access. - */ - { - "Basic COW after fork() with mprotect() optimization", - test_cow_in_parent_mprotect, - }, - /* - * vmsplice() [R/O GUP] + unmap in the child; modify in the parent. If - * we miss to break COW, the child observes modifications by the parent. - * This is CVE-2020-29374 reported by Jann Horn. - */ - { - "vmsplice() + unmap in child", - test_vmsplice_in_child - }, - /* - * vmsplice() test, but do an additional mprotect(PROT_READ)+ - * mprotect(PROT_READ|PROT_WRITE) in the parent before write access. - */ - { - "vmsplice() + unmap in child with mprotect() optimization", - test_vmsplice_in_child_mprotect - }, - /* - * vmsplice() [R/O GUP] in parent before fork(), unmap in parent after - * fork(); modify in the child. If we miss to break COW, the parent - * observes modifications by the child. - */ - { - "vmsplice() before fork(), unmap in parent after fork()", - test_vmsplice_before_fork, - }, - /* - * vmsplice() [R/O GUP] + unmap in parent after fork(); modify in the - * child. If we miss to break COW, the parent observes modifications by - * the child. - */ - { - "vmsplice() + unmap in parent after fork()", - test_vmsplice_after_fork, - }, -#ifdef LOCAL_CONFIG_HAVE_LIBURING - /* - * Take a R/W longterm pin and then map the page R/O into the page - * table to trigger a write fault on next access. When modifying the - * page, the page content must be visible via the pin. - */ - { - "R/O-mapping a page registered as iouring fixed buffer", - test_iouring_ro, - }, - /* - * Take a R/W longterm pin and then fork() a child. When modifying the - * page, the page content must be visible via the pin. We expect the - * pinned page to not get shared with the child. - */ - { - "fork() with an iouring fixed buffer", - test_iouring_fork, - }, - -#endif /* LOCAL_CONFIG_HAVE_LIBURING */ - /* - * Take a R/O longterm pin on a R/O-mapped shared anonymous page. - * When modifying the page via the page table, the page content change - * must be visible via the pin. - */ - { - "R/O GUP pin on R/O-mapped shared page", - test_ro_pin_on_shared, - }, - /* Same as above, but using GUP-fast. */ - { - "R/O GUP-fast pin on R/O-mapped shared page", - test_ro_fast_pin_on_shared, - }, - /* - * Take a R/O longterm pin on a R/O-mapped exclusive anonymous page that - * was previously shared. When modifying the page via the page table, - * the page content change must be visible via the pin. - */ - { - "R/O GUP pin on R/O-mapped previously-shared page", - test_ro_pin_on_ro_previously_shared, - }, - /* Same as above, but using GUP-fast. */ - { - "R/O GUP-fast pin on R/O-mapped previously-shared page", - test_ro_fast_pin_on_ro_previously_shared, - }, - /* - * Take a R/O longterm pin on a R/O-mapped exclusive anonymous page. - * When modifying the page via the page table, the page content change - * must be visible via the pin. - */ - { - "R/O GUP pin on R/O-mapped exclusive page", - test_ro_pin_on_ro_exclusive, - }, - /* Same as above, but using GUP-fast. */ - { - "R/O GUP-fast pin on R/O-mapped exclusive page", - test_ro_fast_pin_on_ro_exclusive, - }, -}; - -static void run_test_case(struct test_case const *test_case) -{ - int i; - - run_with_base_page(test_case->fn, test_case->desc); - run_with_base_page_swap(test_case->fn, test_case->desc); - if (thpsize) { - run_with_thp(test_case->fn, test_case->desc); - run_with_thp_swap(test_case->fn, test_case->desc); - run_with_pte_mapped_thp(test_case->fn, test_case->desc); - run_with_pte_mapped_thp_swap(test_case->fn, test_case->desc); - run_with_single_pte_of_thp(test_case->fn, test_case->desc); - run_with_single_pte_of_thp_swap(test_case->fn, test_case->desc); - run_with_partial_mremap_thp(test_case->fn, test_case->desc); - run_with_partial_shared_thp(test_case->fn, test_case->desc); - } - for (i = 0; i < nr_hugetlbsizes; i++) - run_with_hugetlb(test_case->fn, test_case->desc, - hugetlbsizes[i]); -} - -static void run_test_cases(void) -{ - int i; - - for (i = 0; i < ARRAY_SIZE(test_cases); i++) - run_test_case(&test_cases[i]); -} - -static int tests_per_test_case(void) -{ - int tests = 2 + nr_hugetlbsizes; - - if (thpsize) - tests += 8; - return tests; -} - -int main(int argc, char **argv) -{ - int nr_test_cases = ARRAY_SIZE(test_cases); - int err; - - pagesize = getpagesize(); - detect_thpsize(); - detect_hugetlbsizes(); - - ksft_print_header(); - ksft_set_plan(nr_test_cases * tests_per_test_case()); - - gup_fd = open("/sys/kernel/debug/gup_test", O_RDWR); - pagemap_fd = open("/proc/self/pagemap", O_RDONLY); - if (pagemap_fd < 0) - ksft_exit_fail_msg("opening pagemap failed\n"); - - run_test_cases(); - - err = ksft_get_fail_cnt(); - if (err) - ksft_exit_fail_msg("%d out of %d tests failed\n", - err, ksft_test_num()); - return ksft_exit_pass(); -} diff --git a/tools/testing/selftests/vm/check_config.sh b/tools/testing/selftests/vm/check_config.sh index 9a44c6520925..bcba3af0acea 100644 --- a/tools/testing/selftests/vm/check_config.sh +++ b/tools/testing/selftests/vm/check_config.sh @@ -21,11 +21,11 @@ $CC -c $tmpfile_c -o $tmpfile_o >/dev/null 2>&1 if [ -f $tmpfile_o ]; then echo "#define LOCAL_CONFIG_HAVE_LIBURING 1" > $OUTPUT_H_FILE - echo "ANON_COW_EXTRA_LIBS = -luring" > $OUTPUT_MKFILE + echo "COW_EXTRA_LIBS = -luring" > $OUTPUT_MKFILE else echo "// No liburing support found" > $OUTPUT_H_FILE echo "# No liburing support found, so:" > $OUTPUT_MKFILE - echo "ANON_COW_EXTRA_LIBS = " >> $OUTPUT_MKFILE + echo "COW_EXTRA_LIBS = " >> $OUTPUT_MKFILE fi rm ${tmpname}.* diff --git a/tools/testing/selftests/vm/cow.c b/tools/testing/selftests/vm/cow.c new file mode 100644 index 000000000000..d202bfd63585 --- /dev/null +++ b/tools/testing/selftests/vm/cow.c @@ -0,0 +1,1174 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * COW (Copy On Write) tests. + * + * Copyright 2022, Red Hat, Inc. + * + * Author(s): David Hildenbrand + */ +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "local_config.h" +#ifdef LOCAL_CONFIG_HAVE_LIBURING +#include +#endif /* LOCAL_CONFIG_HAVE_LIBURING */ + +#include "../../../../mm/gup_test.h" +#include "../kselftest.h" +#include "vm_util.h" + +static size_t pagesize; +static int pagemap_fd; +static size_t thpsize; +static int nr_hugetlbsizes; +static size_t hugetlbsizes[10]; +static int gup_fd; + +static void detect_thpsize(void) +{ + int fd = open("/sys/kernel/mm/transparent_hugepage/hpage_pmd_size", + O_RDONLY); + size_t size = 0; + char buf[15]; + int ret; + + if (fd < 0) + return; + + ret = pread(fd, buf, sizeof(buf), 0); + if (ret > 0 && ret < sizeof(buf)) { + buf[ret] = 0; + + size = strtoul(buf, NULL, 10); + if (size < pagesize) + size = 0; + if (size > 0) { + thpsize = size; + ksft_print_msg("[INFO] detected THP size: %zu KiB\n", + thpsize / 1024); + } + } + + close(fd); +} + +static void detect_hugetlbsizes(void) +{ + DIR *dir = opendir("/sys/kernel/mm/hugepages/"); + + if (!dir) + return; + + while (nr_hugetlbsizes < ARRAY_SIZE(hugetlbsizes)) { + struct dirent *entry = readdir(dir); + size_t kb; + + if (!entry) + break; + if (entry->d_type != DT_DIR) + continue; + if (sscanf(entry->d_name, "hugepages-%zukB", &kb) != 1) + continue; + hugetlbsizes[nr_hugetlbsizes] = kb * 1024; + nr_hugetlbsizes++; + ksft_print_msg("[INFO] detected hugetlb size: %zu KiB\n", + kb); + } + closedir(dir); +} + +static bool range_is_swapped(void *addr, size_t size) +{ + for (; size; addr += pagesize, size -= pagesize) + if (!pagemap_is_swapped(pagemap_fd, addr)) + return false; + return true; +} + +struct comm_pipes { + int child_ready[2]; + int parent_ready[2]; +}; + +static int setup_comm_pipes(struct comm_pipes *comm_pipes) +{ + if (pipe(comm_pipes->child_ready) < 0) + return -errno; + if (pipe(comm_pipes->parent_ready) < 0) { + close(comm_pipes->child_ready[0]); + close(comm_pipes->child_ready[1]); + return -errno; + } + + return 0; +} + +static void close_comm_pipes(struct comm_pipes *comm_pipes) +{ + close(comm_pipes->child_ready[0]); + close(comm_pipes->child_ready[1]); + close(comm_pipes->parent_ready[0]); + close(comm_pipes->parent_ready[1]); +} + +static int child_memcmp_fn(char *mem, size_t size, + struct comm_pipes *comm_pipes) +{ + char *old = malloc(size); + char buf; + + /* Backup the original content. */ + memcpy(old, mem, size); + + /* Wait until the parent modified the page. */ + write(comm_pipes->child_ready[1], "0", 1); + while (read(comm_pipes->parent_ready[0], &buf, 1) != 1) + ; + + /* See if we still read the old values. */ + return memcmp(old, mem, size); +} + +static int child_vmsplice_memcmp_fn(char *mem, size_t size, + struct comm_pipes *comm_pipes) +{ + struct iovec iov = { + .iov_base = mem, + .iov_len = size, + }; + ssize_t cur, total, transferred; + char *old, *new; + int fds[2]; + char buf; + + old = malloc(size); + new = malloc(size); + + /* Backup the original content. */ + memcpy(old, mem, size); + + if (pipe(fds) < 0) + return -errno; + + /* Trigger a read-only pin. */ + transferred = vmsplice(fds[1], &iov, 1, 0); + if (transferred < 0) + return -errno; + if (transferred == 0) + return -EINVAL; + + /* Unmap it from our page tables. */ + if (munmap(mem, size) < 0) + return -errno; + + /* Wait until the parent modified it. */ + write(comm_pipes->child_ready[1], "0", 1); + while (read(comm_pipes->parent_ready[0], &buf, 1) != 1) + ; + + /* See if we still read the old values via the pipe. */ + for (total = 0; total < transferred; total += cur) { + cur = read(fds[0], new + total, transferred - total); + if (cur < 0) + return -errno; + } + + return memcmp(old, new, transferred); +} + +typedef int (*child_fn)(char *mem, size_t size, struct comm_pipes *comm_pipes); + +static void do_test_cow_in_parent(char *mem, size_t size, bool do_mprotect, + child_fn fn) +{ + struct comm_pipes comm_pipes; + char buf; + int ret; + + ret = setup_comm_pipes(&comm_pipes); + if (ret) { + ksft_test_result_fail("pipe() failed\n"); + return; + } + + ret = fork(); + if (ret < 0) { + ksft_test_result_fail("fork() failed\n"); + goto close_comm_pipes; + } else if (!ret) { + exit(fn(mem, size, &comm_pipes)); + } + + while (read(comm_pipes.child_ready[0], &buf, 1) != 1) + ; + + if (do_mprotect) { + /* + * mprotect() optimizations might try avoiding + * write-faults by directly mapping pages writable. + */ + ret = mprotect(mem, size, PROT_READ); + ret |= mprotect(mem, size, PROT_READ|PROT_WRITE); + if (ret) { + ksft_test_result_fail("mprotect() failed\n"); + write(comm_pipes.parent_ready[1], "0", 1); + wait(&ret); + goto close_comm_pipes; + } + } + + /* Modify the page. */ + memset(mem, 0xff, size); + write(comm_pipes.parent_ready[1], "0", 1); + + wait(&ret); + if (WIFEXITED(ret)) + ret = WEXITSTATUS(ret); + else + ret = -EINVAL; + + ksft_test_result(!ret, "No leak from parent into child\n"); +close_comm_pipes: + close_comm_pipes(&comm_pipes); +} + +static void test_cow_in_parent(char *mem, size_t size) +{ + do_test_cow_in_parent(mem, size, false, child_memcmp_fn); +} + +static void test_cow_in_parent_mprotect(char *mem, size_t size) +{ + do_test_cow_in_parent(mem, size, true, child_memcmp_fn); +} + +static void test_vmsplice_in_child(char *mem, size_t size) +{ + do_test_cow_in_parent(mem, size, false, child_vmsplice_memcmp_fn); +} + +static void test_vmsplice_in_child_mprotect(char *mem, size_t size) +{ + do_test_cow_in_parent(mem, size, true, child_vmsplice_memcmp_fn); +} + +static void do_test_vmsplice_in_parent(char *mem, size_t size, + bool before_fork) +{ + struct iovec iov = { + .iov_base = mem, + .iov_len = size, + }; + ssize_t cur, total, transferred; + struct comm_pipes comm_pipes; + char *old, *new; + int ret, fds[2]; + char buf; + + old = malloc(size); + new = malloc(size); + + memcpy(old, mem, size); + + ret = setup_comm_pipes(&comm_pipes); + if (ret) { + ksft_test_result_fail("pipe() failed\n"); + goto free; + } + + if (pipe(fds) < 0) { + ksft_test_result_fail("pipe() failed\n"); + goto close_comm_pipes; + } + + if (before_fork) { + transferred = vmsplice(fds[1], &iov, 1, 0); + if (transferred <= 0) { + ksft_test_result_fail("vmsplice() failed\n"); + goto close_pipe; + } + } + + ret = fork(); + if (ret < 0) { + ksft_test_result_fail("fork() failed\n"); + goto close_pipe; + } else if (!ret) { + write(comm_pipes.child_ready[1], "0", 1); + while (read(comm_pipes.parent_ready[0], &buf, 1) != 1) + ; + /* Modify page content in the child. */ + memset(mem, 0xff, size); + exit(0); + } + + if (!before_fork) { + transferred = vmsplice(fds[1], &iov, 1, 0); + if (transferred <= 0) { + ksft_test_result_fail("vmsplice() failed\n"); + wait(&ret); + goto close_pipe; + } + } + + while (read(comm_pipes.child_ready[0], &buf, 1) != 1) + ; + if (munmap(mem, size) < 0) { + ksft_test_result_fail("munmap() failed\n"); + goto close_pipe; + } + write(comm_pipes.parent_ready[1], "0", 1); + + /* Wait until the child is done writing. */ + wait(&ret); + if (!WIFEXITED(ret)) { + ksft_test_result_fail("wait() failed\n"); + goto close_pipe; + } + + /* See if we still read the old values. */ + for (total = 0; total < transferred; total += cur) { + cur = read(fds[0], new + total, transferred - total); + if (cur < 0) { + ksft_test_result_fail("read() failed\n"); + goto close_pipe; + } + } + + ksft_test_result(!memcmp(old, new, transferred), + "No leak from child into parent\n"); +close_pipe: + close(fds[0]); + close(fds[1]); +close_comm_pipes: + close_comm_pipes(&comm_pipes); +free: + free(old); + free(new); +} + +static void test_vmsplice_before_fork(char *mem, size_t size) +{ + do_test_vmsplice_in_parent(mem, size, true); +} + +static void test_vmsplice_after_fork(char *mem, size_t size) +{ + do_test_vmsplice_in_parent(mem, size, false); +} + +#ifdef LOCAL_CONFIG_HAVE_LIBURING +static void do_test_iouring(char *mem, size_t size, bool use_fork) +{ + struct comm_pipes comm_pipes; + struct io_uring_cqe *cqe; + struct io_uring_sqe *sqe; + struct io_uring ring; + ssize_t cur, total; + struct iovec iov; + char *buf, *tmp; + int ret, fd; + FILE *file; + + ret = setup_comm_pipes(&comm_pipes); + if (ret) { + ksft_test_result_fail("pipe() failed\n"); + return; + } + + file = tmpfile(); + if (!file) { + ksft_test_result_fail("tmpfile() failed\n"); + goto close_comm_pipes; + } + fd = fileno(file); + assert(fd); + + tmp = malloc(size); + if (!tmp) { + ksft_test_result_fail("malloc() failed\n"); + goto close_file; + } + + /* Skip on errors, as we might just lack kernel support. */ + ret = io_uring_queue_init(1, &ring, 0); + if (ret < 0) { + ksft_test_result_skip("io_uring_queue_init() failed\n"); + goto free_tmp; + } + + /* + * Register the range as a fixed buffer. This will FOLL_WRITE | FOLL_PIN + * | FOLL_LONGTERM the range. + * + * Skip on errors, as we might just lack kernel support or might not + * have sufficient MEMLOCK permissions. + */ + iov.iov_base = mem; + iov.iov_len = size; + ret = io_uring_register_buffers(&ring, &iov, 1); + if (ret) { + ksft_test_result_skip("io_uring_register_buffers() failed\n"); + goto queue_exit; + } + + if (use_fork) { + /* + * fork() and keep the child alive until we're done. Note that + * we expect the pinned page to not get shared with the child. + */ + ret = fork(); + if (ret < 0) { + ksft_test_result_fail("fork() failed\n"); + goto unregister_buffers; + } else if (!ret) { + write(comm_pipes.child_ready[1], "0", 1); + while (read(comm_pipes.parent_ready[0], &buf, 1) != 1) + ; + exit(0); + } + + while (read(comm_pipes.child_ready[0], &buf, 1) != 1) + ; + } else { + /* + * Map the page R/O into the page table. Enable softdirty + * tracking to stop the page from getting mapped R/W immediately + * again by mprotect() optimizations. Note that we don't have an + * easy way to test if that worked (the pagemap does not export + * if the page is mapped R/O vs. R/W). + */ + ret = mprotect(mem, size, PROT_READ); + clear_softdirty(); + ret |= mprotect(mem, size, PROT_READ | PROT_WRITE); + if (ret) { + ksft_test_result_fail("mprotect() failed\n"); + goto unregister_buffers; + } + } + + /* + * Modify the page and write page content as observed by the fixed + * buffer pin to the file so we can verify it. + */ + memset(mem, 0xff, size); + sqe = io_uring_get_sqe(&ring); + if (!sqe) { + ksft_test_result_fail("io_uring_get_sqe() failed\n"); + goto quit_child; + } + io_uring_prep_write_fixed(sqe, fd, mem, size, 0, 0); + + ret = io_uring_submit(&ring); + if (ret < 0) { + ksft_test_result_fail("io_uring_submit() failed\n"); + goto quit_child; + } + + ret = io_uring_wait_cqe(&ring, &cqe); + if (ret < 0) { + ksft_test_result_fail("io_uring_wait_cqe() failed\n"); + goto quit_child; + } + + if (cqe->res != size) { + ksft_test_result_fail("write_fixed failed\n"); + goto quit_child; + } + io_uring_cqe_seen(&ring, cqe); + + /* Read back the file content to the temporary buffer. */ + total = 0; + while (total < size) { + cur = pread(fd, tmp + total, size - total, total); + if (cur < 0) { + ksft_test_result_fail("pread() failed\n"); + goto quit_child; + } + total += cur; + } + + /* Finally, check if we read what we expected. */ + ksft_test_result(!memcmp(mem, tmp, size), + "Longterm R/W pin is reliable\n"); + +quit_child: + if (use_fork) { + write(comm_pipes.parent_ready[1], "0", 1); + wait(&ret); + } +unregister_buffers: + io_uring_unregister_buffers(&ring); +queue_exit: + io_uring_queue_exit(&ring); +free_tmp: + free(tmp); +close_file: + fclose(file); +close_comm_pipes: + close_comm_pipes(&comm_pipes); +} + +static void test_iouring_ro(char *mem, size_t size) +{ + do_test_iouring(mem, size, false); +} + +static void test_iouring_fork(char *mem, size_t size) +{ + do_test_iouring(mem, size, true); +} + +#endif /* LOCAL_CONFIG_HAVE_LIBURING */ + +enum ro_pin_test { + RO_PIN_TEST_SHARED, + RO_PIN_TEST_PREVIOUSLY_SHARED, + RO_PIN_TEST_RO_EXCLUSIVE, +}; + +static void do_test_ro_pin(char *mem, size_t size, enum ro_pin_test test, + bool fast) +{ + struct pin_longterm_test args; + struct comm_pipes comm_pipes; + char *tmp, buf; + __u64 tmp_val; + int ret; + + if (gup_fd < 0) { + ksft_test_result_skip("gup_test not available\n"); + return; + } + + tmp = malloc(size); + if (!tmp) { + ksft_test_result_fail("malloc() failed\n"); + return; + } + + ret = setup_comm_pipes(&comm_pipes); + if (ret) { + ksft_test_result_fail("pipe() failed\n"); + goto free_tmp; + } + + switch (test) { + case RO_PIN_TEST_SHARED: + case RO_PIN_TEST_PREVIOUSLY_SHARED: + /* + * Share the pages with our child. As the pages are not pinned, + * this should just work. + */ + ret = fork(); + if (ret < 0) { + ksft_test_result_fail("fork() failed\n"); + goto close_comm_pipes; + } else if (!ret) { + write(comm_pipes.child_ready[1], "0", 1); + while (read(comm_pipes.parent_ready[0], &buf, 1) != 1) + ; + exit(0); + } + + /* Wait until our child is ready. */ + while (read(comm_pipes.child_ready[0], &buf, 1) != 1) + ; + + if (test == RO_PIN_TEST_PREVIOUSLY_SHARED) { + /* + * Tell the child to quit now and wait until it quit. + * The pages should now be mapped R/O into our page + * tables, but they are no longer shared. + */ + write(comm_pipes.parent_ready[1], "0", 1); + wait(&ret); + if (!WIFEXITED(ret)) + ksft_print_msg("[INFO] wait() failed\n"); + } + break; + case RO_PIN_TEST_RO_EXCLUSIVE: + /* + * Map the page R/O into the page table. Enable softdirty + * tracking to stop the page from getting mapped R/W immediately + * again by mprotect() optimizations. Note that we don't have an + * easy way to test if that worked (the pagemap does not export + * if the page is mapped R/O vs. R/W). + */ + ret = mprotect(mem, size, PROT_READ); + clear_softdirty(); + ret |= mprotect(mem, size, PROT_READ | PROT_WRITE); + if (ret) { + ksft_test_result_fail("mprotect() failed\n"); + goto close_comm_pipes; + } + break; + default: + assert(false); + } + + /* Take a R/O pin. This should trigger unsharing. */ + args.addr = (__u64)mem; + args.size = size; + args.flags = fast ? PIN_LONGTERM_TEST_FLAG_USE_FAST : 0; + ret = ioctl(gup_fd, PIN_LONGTERM_TEST_START, &args); + if (ret) { + if (errno == EINVAL) + ksft_test_result_skip("PIN_LONGTERM_TEST_START failed\n"); + else + ksft_test_result_fail("PIN_LONGTERM_TEST_START failed\n"); + goto wait; + } + + /* Modify the page. */ + memset(mem, 0xff, size); + + /* + * Read back the content via the pin to the temporary buffer and + * test if we observed the modification. + */ + tmp_val = (__u64)tmp; + ret = ioctl(gup_fd, PIN_LONGTERM_TEST_READ, &tmp_val); + if (ret) + ksft_test_result_fail("PIN_LONGTERM_TEST_READ failed\n"); + else + ksft_test_result(!memcmp(mem, tmp, size), + "Longterm R/O pin is reliable\n"); + + ret = ioctl(gup_fd, PIN_LONGTERM_TEST_STOP); + if (ret) + ksft_print_msg("[INFO] PIN_LONGTERM_TEST_STOP failed\n"); +wait: + switch (test) { + case RO_PIN_TEST_SHARED: + write(comm_pipes.parent_ready[1], "0", 1); + wait(&ret); + if (!WIFEXITED(ret)) + ksft_print_msg("[INFO] wait() failed\n"); + break; + default: + break; + } +close_comm_pipes: + close_comm_pipes(&comm_pipes); +free_tmp: + free(tmp); +} + +static void test_ro_pin_on_shared(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_SHARED, false); +} + +static void test_ro_fast_pin_on_shared(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_SHARED, true); +} + +static void test_ro_pin_on_ro_previously_shared(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_PREVIOUSLY_SHARED, false); +} + +static void test_ro_fast_pin_on_ro_previously_shared(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_PREVIOUSLY_SHARED, true); +} + +static void test_ro_pin_on_ro_exclusive(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_RO_EXCLUSIVE, false); +} + +static void test_ro_fast_pin_on_ro_exclusive(char *mem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST_RO_EXCLUSIVE, true); +} + +typedef void (*test_fn)(char *mem, size_t size); + +static void do_run_with_base_page(test_fn fn, bool swapout) +{ + char *mem; + int ret; + + mem = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + return; + } + + ret = madvise(mem, pagesize, MADV_NOHUGEPAGE); + /* Ignore if not around on a kernel. */ + if (ret && errno != EINVAL) { + ksft_test_result_fail("MADV_NOHUGEPAGE failed\n"); + goto munmap; + } + + /* Populate a base page. */ + memset(mem, 0, pagesize); + + if (swapout) { + madvise(mem, pagesize, MADV_PAGEOUT); + if (!pagemap_is_swapped(pagemap_fd, mem)) { + ksft_test_result_skip("MADV_PAGEOUT did not work, is swap enabled?\n"); + goto munmap; + } + } + + fn(mem, pagesize); +munmap: + munmap(mem, pagesize); +} + +static void run_with_base_page(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with base page\n", desc); + do_run_with_base_page(fn, false); +} + +static void run_with_base_page_swap(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with swapped out base page\n", desc); + do_run_with_base_page(fn, true); +} + +enum thp_run { + THP_RUN_PMD, + THP_RUN_PMD_SWAPOUT, + THP_RUN_PTE, + THP_RUN_PTE_SWAPOUT, + THP_RUN_SINGLE_PTE, + THP_RUN_SINGLE_PTE_SWAPOUT, + THP_RUN_PARTIAL_MREMAP, + THP_RUN_PARTIAL_SHARED, +}; + +static void do_run_with_thp(test_fn fn, enum thp_run thp_run) +{ + char *mem, *mmap_mem, *tmp, *mremap_mem = MAP_FAILED; + size_t size, mmap_size, mremap_size; + int ret; + + /* For alignment purposes, we need twice the thp size. */ + mmap_size = 2 * thpsize; + mmap_mem = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (mmap_mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + return; + } + + /* We need a THP-aligned memory area. */ + mem = (char *)(((uintptr_t)mmap_mem + thpsize) & ~(thpsize - 1)); + + ret = madvise(mem, thpsize, MADV_HUGEPAGE); + if (ret) { + ksft_test_result_fail("MADV_HUGEPAGE failed\n"); + goto munmap; + } + + /* + * Try to populate a THP. Touch the first sub-page and test if we get + * another sub-page populated automatically. + */ + mem[0] = 0; + if (!pagemap_is_populated(pagemap_fd, mem + pagesize)) { + ksft_test_result_skip("Did not get a THP populated\n"); + goto munmap; + } + memset(mem, 0, thpsize); + + size = thpsize; + switch (thp_run) { + case THP_RUN_PMD: + case THP_RUN_PMD_SWAPOUT: + break; + case THP_RUN_PTE: + case THP_RUN_PTE_SWAPOUT: + /* + * Trigger PTE-mapping the THP by temporarily mapping a single + * subpage R/O. + */ + ret = mprotect(mem + pagesize, pagesize, PROT_READ); + if (ret) { + ksft_test_result_fail("mprotect() failed\n"); + goto munmap; + } + ret = mprotect(mem + pagesize, pagesize, PROT_READ | PROT_WRITE); + if (ret) { + ksft_test_result_fail("mprotect() failed\n"); + goto munmap; + } + break; + case THP_RUN_SINGLE_PTE: + case THP_RUN_SINGLE_PTE_SWAPOUT: + /* + * Discard all but a single subpage of that PTE-mapped THP. What + * remains is a single PTE mapping a single subpage. + */ + ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DONTNEED); + if (ret) { + ksft_test_result_fail("MADV_DONTNEED failed\n"); + goto munmap; + } + size = pagesize; + break; + case THP_RUN_PARTIAL_MREMAP: + /* + * Remap half of the THP. We need some new memory location + * for that. + */ + mremap_size = thpsize / 2; + mremap_mem = mmap(NULL, mremap_size, PROT_NONE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + goto munmap; + } + tmp = mremap(mem + mremap_size, mremap_size, mremap_size, + MREMAP_MAYMOVE | MREMAP_FIXED, mremap_mem); + if (tmp != mremap_mem) { + ksft_test_result_fail("mremap() failed\n"); + goto munmap; + } + size = mremap_size; + break; + case THP_RUN_PARTIAL_SHARED: + /* + * Share the first page of the THP with a child and quit the + * child. This will result in some parts of the THP never + * have been shared. + */ + ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DONTFORK); + if (ret) { + ksft_test_result_fail("MADV_DONTFORK failed\n"); + goto munmap; + } + ret = fork(); + if (ret < 0) { + ksft_test_result_fail("fork() failed\n"); + goto munmap; + } else if (!ret) { + exit(0); + } + wait(&ret); + /* Allow for sharing all pages again. */ + ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DOFORK); + if (ret) { + ksft_test_result_fail("MADV_DOFORK failed\n"); + goto munmap; + } + break; + default: + assert(false); + } + + switch (thp_run) { + case THP_RUN_PMD_SWAPOUT: + case THP_RUN_PTE_SWAPOUT: + case THP_RUN_SINGLE_PTE_SWAPOUT: + madvise(mem, size, MADV_PAGEOUT); + if (!range_is_swapped(mem, size)) { + ksft_test_result_skip("MADV_PAGEOUT did not work, is swap enabled?\n"); + goto munmap; + } + break; + default: + break; + } + + fn(mem, size); +munmap: + munmap(mmap_mem, mmap_size); + if (mremap_mem != MAP_FAILED) + munmap(mremap_mem, mremap_size); +} + +static void run_with_thp(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with THP\n", desc); + do_run_with_thp(fn, THP_RUN_PMD); +} + +static void run_with_thp_swap(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with swapped-out THP\n", desc); + do_run_with_thp(fn, THP_RUN_PMD_SWAPOUT); +} + +static void run_with_pte_mapped_thp(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with PTE-mapped THP\n", desc); + do_run_with_thp(fn, THP_RUN_PTE); +} + +static void run_with_pte_mapped_thp_swap(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with swapped-out, PTE-mapped THP\n", desc); + do_run_with_thp(fn, THP_RUN_PTE_SWAPOUT); +} + +static void run_with_single_pte_of_thp(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with single PTE of THP\n", desc); + do_run_with_thp(fn, THP_RUN_SINGLE_PTE); +} + +static void run_with_single_pte_of_thp_swap(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with single PTE of swapped-out THP\n", desc); + do_run_with_thp(fn, THP_RUN_SINGLE_PTE_SWAPOUT); +} + +static void run_with_partial_mremap_thp(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with partially mremap()'ed THP\n", desc); + do_run_with_thp(fn, THP_RUN_PARTIAL_MREMAP); +} + +static void run_with_partial_shared_thp(test_fn fn, const char *desc) +{ + ksft_print_msg("[RUN] %s ... with partially shared THP\n", desc); + do_run_with_thp(fn, THP_RUN_PARTIAL_SHARED); +} + +static void run_with_hugetlb(test_fn fn, const char *desc, size_t hugetlbsize) +{ + int flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB; + char *mem, *dummy; + + ksft_print_msg("[RUN] %s ... with hugetlb (%zu kB)\n", desc, + hugetlbsize / 1024); + + flags |= __builtin_ctzll(hugetlbsize) << MAP_HUGE_SHIFT; + + mem = mmap(NULL, hugetlbsize, PROT_READ | PROT_WRITE, flags, -1, 0); + if (mem == MAP_FAILED) { + ksft_test_result_skip("need more free huge pages\n"); + return; + } + + /* Populate an huge page. */ + memset(mem, 0, hugetlbsize); + + /* + * We need a total of two hugetlb pages to handle COW/unsharing + * properly, otherwise we might get zapped by a SIGBUS. + */ + dummy = mmap(NULL, hugetlbsize, PROT_READ | PROT_WRITE, flags, -1, 0); + if (dummy == MAP_FAILED) { + ksft_test_result_skip("need more free huge pages\n"); + goto munmap; + } + munmap(dummy, hugetlbsize); + + fn(mem, hugetlbsize); +munmap: + munmap(mem, hugetlbsize); +} + +struct test_case { + const char *desc; + test_fn fn; +}; + +/* + * Test cases that are specific to anonymous pages: pages in private mappings + * that may get shared via COW during fork(). + */ +static const struct test_case anon_test_cases[] = { + /* + * Basic COW tests for fork() without any GUP. If we miss to break COW, + * either the child can observe modifications by the parent or the + * other way around. + */ + { + "Basic COW after fork()", + test_cow_in_parent, + }, + /* + * Basic test, but do an additional mprotect(PROT_READ)+ + * mprotect(PROT_READ|PROT_WRITE) in the parent before write access. + */ + { + "Basic COW after fork() with mprotect() optimization", + test_cow_in_parent_mprotect, + }, + /* + * vmsplice() [R/O GUP] + unmap in the child; modify in the parent. If + * we miss to break COW, the child observes modifications by the parent. + * This is CVE-2020-29374 reported by Jann Horn. + */ + { + "vmsplice() + unmap in child", + test_vmsplice_in_child + }, + /* + * vmsplice() test, but do an additional mprotect(PROT_READ)+ + * mprotect(PROT_READ|PROT_WRITE) in the parent before write access. + */ + { + "vmsplice() + unmap in child with mprotect() optimization", + test_vmsplice_in_child_mprotect + }, + /* + * vmsplice() [R/O GUP] in parent before fork(), unmap in parent after + * fork(); modify in the child. If we miss to break COW, the parent + * observes modifications by the child. + */ + { + "vmsplice() before fork(), unmap in parent after fork()", + test_vmsplice_before_fork, + }, + /* + * vmsplice() [R/O GUP] + unmap in parent after fork(); modify in the + * child. If we miss to break COW, the parent observes modifications by + * the child. + */ + { + "vmsplice() + unmap in parent after fork()", + test_vmsplice_after_fork, + }, +#ifdef LOCAL_CONFIG_HAVE_LIBURING + /* + * Take a R/W longterm pin and then map the page R/O into the page + * table to trigger a write fault on next access. When modifying the + * page, the page content must be visible via the pin. + */ + { + "R/O-mapping a page registered as iouring fixed buffer", + test_iouring_ro, + }, + /* + * Take a R/W longterm pin and then fork() a child. When modifying the + * page, the page content must be visible via the pin. We expect the + * pinned page to not get shared with the child. + */ + { + "fork() with an iouring fixed buffer", + test_iouring_fork, + }, + +#endif /* LOCAL_CONFIG_HAVE_LIBURING */ + /* + * Take a R/O longterm pin on a R/O-mapped shared anonymous page. + * When modifying the page via the page table, the page content change + * must be visible via the pin. + */ + { + "R/O GUP pin on R/O-mapped shared page", + test_ro_pin_on_shared, + }, + /* Same as above, but using GUP-fast. */ + { + "R/O GUP-fast pin on R/O-mapped shared page", + test_ro_fast_pin_on_shared, + }, + /* + * Take a R/O longterm pin on a R/O-mapped exclusive anonymous page that + * was previously shared. When modifying the page via the page table, + * the page content change must be visible via the pin. + */ + { + "R/O GUP pin on R/O-mapped previously-shared page", + test_ro_pin_on_ro_previously_shared, + }, + /* Same as above, but using GUP-fast. */ + { + "R/O GUP-fast pin on R/O-mapped previously-shared page", + test_ro_fast_pin_on_ro_previously_shared, + }, + /* + * Take a R/O longterm pin on a R/O-mapped exclusive anonymous page. + * When modifying the page via the page table, the page content change + * must be visible via the pin. + */ + { + "R/O GUP pin on R/O-mapped exclusive page", + test_ro_pin_on_ro_exclusive, + }, + /* Same as above, but using GUP-fast. */ + { + "R/O GUP-fast pin on R/O-mapped exclusive page", + test_ro_fast_pin_on_ro_exclusive, + }, +}; + +static void run_anon_test_case(struct test_case const *test_case) +{ + int i; + + run_with_base_page(test_case->fn, test_case->desc); + run_with_base_page_swap(test_case->fn, test_case->desc); + if (thpsize) { + run_with_thp(test_case->fn, test_case->desc); + run_with_thp_swap(test_case->fn, test_case->desc); + run_with_pte_mapped_thp(test_case->fn, test_case->desc); + run_with_pte_mapped_thp_swap(test_case->fn, test_case->desc); + run_with_single_pte_of_thp(test_case->fn, test_case->desc); + run_with_single_pte_of_thp_swap(test_case->fn, test_case->desc); + run_with_partial_mremap_thp(test_case->fn, test_case->desc); + run_with_partial_shared_thp(test_case->fn, test_case->desc); + } + for (i = 0; i < nr_hugetlbsizes; i++) + run_with_hugetlb(test_case->fn, test_case->desc, + hugetlbsizes[i]); +} + +static void run_anon_test_cases(void) +{ + int i; + + ksft_print_msg("[INFO] Anonymous memory tests in private mappings\n"); + + for (i = 0; i < ARRAY_SIZE(anon_test_cases); i++) + run_anon_test_case(&anon_test_cases[i]); +} + +static int tests_per_anon_test_case(void) +{ + int tests = 2 + nr_hugetlbsizes; + + if (thpsize) + tests += 8; + return tests; +} + +int main(int argc, char **argv) +{ + int err; + + pagesize = getpagesize(); + detect_thpsize(); + detect_hugetlbsizes(); + + ksft_print_header(); + ksft_set_plan(ARRAY_SIZE(anon_test_cases) * tests_per_anon_test_case()); + + gup_fd = open("/sys/kernel/debug/gup_test", O_RDWR); + pagemap_fd = open("/proc/self/pagemap", O_RDONLY); + if (pagemap_fd < 0) + ksft_exit_fail_msg("opening pagemap failed\n"); + + run_anon_test_cases(); + + err = ksft_get_fail_cnt(); + if (err) + ksft_exit_fail_msg("%d out of %d tests failed\n", + err, ksft_test_num()); + return ksft_exit_pass(); +} diff --git a/tools/testing/selftests/vm/run_vmtests.sh b/tools/testing/selftests/vm/run_vmtests.sh index 1fa783732296..54d7a822c2ce 100755 --- a/tools/testing/selftests/vm/run_vmtests.sh +++ b/tools/testing/selftests/vm/run_vmtests.sh @@ -186,6 +186,6 @@ fi run_test ./soft-dirty # COW tests for anonymous memory -run_test ./anon_cow +run_test ./cow exit $exitcode -- cgit v1.2.3 From f8664f3c4a08f799122e8f0a8093056a7b3fbc8d Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Wed, 16 Nov 2022 11:26:41 +0100 Subject: selftests/vm: cow: basic COW tests for non-anonymous pages Let's add basic tests for COW with non-anonymous pages in private mappings: write access should properly trigger COW and result in the private changes not being visible through other page mappings. Especially, add tests for: * Zeropage * Huge zeropage * Ordinary pagecache pages via memfd and tmpfile() * Hugetlb pages via memfd Fortunately, all tests pass. Link: https://lkml.kernel.org/r/20221116102659.70287-3-david@redhat.com Signed-off-by: David Hildenbrand Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/cow.c | 338 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 337 insertions(+), 1 deletion(-) (limited to 'tools') diff --git a/tools/testing/selftests/vm/cow.c b/tools/testing/selftests/vm/cow.c index d202bfd63585..fb07bd44529c 100644 --- a/tools/testing/selftests/vm/cow.c +++ b/tools/testing/selftests/vm/cow.c @@ -19,6 +19,7 @@ #include #include #include +#include #include "local_config.h" #ifdef LOCAL_CONFIG_HAVE_LIBURING @@ -35,6 +36,7 @@ static size_t thpsize; static int nr_hugetlbsizes; static size_t hugetlbsizes[10]; static int gup_fd; +static bool has_huge_zeropage; static void detect_thpsize(void) { @@ -64,6 +66,31 @@ static void detect_thpsize(void) close(fd); } +static void detect_huge_zeropage(void) +{ + int fd = open("/sys/kernel/mm/transparent_hugepage/use_zero_page", + O_RDONLY); + size_t enabled = 0; + char buf[15]; + int ret; + + if (fd < 0) + return; + + ret = pread(fd, buf, sizeof(buf), 0); + if (ret > 0 && ret < sizeof(buf)) { + buf[ret] = 0; + + enabled = strtoul(buf, NULL, 10); + if (enabled == 1) { + has_huge_zeropage = true; + ksft_print_msg("[INFO] huge zeropage is enabled\n"); + } + } + + close(fd); +} + static void detect_hugetlbsizes(void) { DIR *dir = opendir("/sys/kernel/mm/hugepages/"); @@ -1148,6 +1175,312 @@ static int tests_per_anon_test_case(void) return tests; } +typedef void (*non_anon_test_fn)(char *mem, const char *smem, size_t size); + +static void test_cow(char *mem, const char *smem, size_t size) +{ + char *old = malloc(size); + + /* Backup the original content. */ + memcpy(old, smem, size); + + /* Modify the page. */ + memset(mem, 0xff, size); + + /* See if we still read the old values via the other mapping. */ + ksft_test_result(!memcmp(smem, old, size), + "Other mapping not modified\n"); + free(old); +} + +static void run_with_zeropage(non_anon_test_fn fn, const char *desc) +{ + char *mem, *smem, tmp; + + ksft_print_msg("[RUN] %s ... with shared zeropage\n", desc); + + mem = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANON, -1, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + return; + } + + smem = mmap(NULL, pagesize, PROT_READ, MAP_PRIVATE | MAP_ANON, -1, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + goto munmap; + } + + /* Read from the page to populate the shared zeropage. */ + tmp = *mem + *smem; + asm volatile("" : "+r" (tmp)); + + fn(mem, smem, pagesize); +munmap: + munmap(mem, pagesize); + if (smem != MAP_FAILED) + munmap(smem, pagesize); +} + +static void run_with_huge_zeropage(non_anon_test_fn fn, const char *desc) +{ + char *mem, *smem, *mmap_mem, *mmap_smem, tmp; + size_t mmap_size; + int ret; + + ksft_print_msg("[RUN] %s ... with huge zeropage\n", desc); + + if (!has_huge_zeropage) { + ksft_test_result_skip("Huge zeropage not enabled\n"); + return; + } + + /* For alignment purposes, we need twice the thp size. */ + mmap_size = 2 * thpsize; + mmap_mem = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (mmap_mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + return; + } + mmap_smem = mmap(NULL, mmap_size, PROT_READ, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (mmap_smem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + goto munmap; + } + + /* We need a THP-aligned memory area. */ + mem = (char *)(((uintptr_t)mmap_mem + thpsize) & ~(thpsize - 1)); + smem = (char *)(((uintptr_t)mmap_smem + thpsize) & ~(thpsize - 1)); + + ret = madvise(mem, thpsize, MADV_HUGEPAGE); + ret |= madvise(smem, thpsize, MADV_HUGEPAGE); + if (ret) { + ksft_test_result_fail("MADV_HUGEPAGE failed\n"); + goto munmap; + } + + /* + * Read from the memory to populate the huge shared zeropage. Read from + * the first sub-page and test if we get another sub-page populated + * automatically. + */ + tmp = *mem + *smem; + asm volatile("" : "+r" (tmp)); + if (!pagemap_is_populated(pagemap_fd, mem + pagesize) || + !pagemap_is_populated(pagemap_fd, smem + pagesize)) { + ksft_test_result_skip("Did not get THPs populated\n"); + goto munmap; + } + + fn(mem, smem, thpsize); +munmap: + munmap(mmap_mem, mmap_size); + if (mmap_smem != MAP_FAILED) + munmap(mmap_smem, mmap_size); +} + +static void run_with_memfd(non_anon_test_fn fn, const char *desc) +{ + char *mem, *smem, tmp; + int fd; + + ksft_print_msg("[RUN] %s ... with memfd\n", desc); + + fd = memfd_create("test", 0); + if (fd < 0) { + ksft_test_result_fail("memfd_create() failed\n"); + return; + } + + /* File consists of a single page filled with zeroes. */ + if (fallocate(fd, 0, 0, pagesize)) { + ksft_test_result_fail("fallocate() failed\n"); + goto close; + } + + /* Create a private mapping of the memfd. */ + mem = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + goto close; + } + smem = mmap(NULL, pagesize, PROT_READ, MAP_SHARED, fd, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + goto munmap; + } + + /* Fault the page in. */ + tmp = *mem + *smem; + asm volatile("" : "+r" (tmp)); + + fn(mem, smem, pagesize); +munmap: + munmap(mem, pagesize); + if (smem != MAP_FAILED) + munmap(smem, pagesize); +close: + close(fd); +} + +static void run_with_tmpfile(non_anon_test_fn fn, const char *desc) +{ + char *mem, *smem, tmp; + FILE *file; + int fd; + + ksft_print_msg("[RUN] %s ... with tmpfile\n", desc); + + file = tmpfile(); + if (!file) { + ksft_test_result_fail("tmpfile() failed\n"); + return; + } + + fd = fileno(file); + if (fd < 0) { + ksft_test_result_skip("fileno() failed\n"); + return; + } + + /* File consists of a single page filled with zeroes. */ + if (fallocate(fd, 0, 0, pagesize)) { + ksft_test_result_fail("fallocate() failed\n"); + goto close; + } + + /* Create a private mapping of the memfd. */ + mem = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + goto close; + } + smem = mmap(NULL, pagesize, PROT_READ, MAP_SHARED, fd, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + goto munmap; + } + + /* Fault the page in. */ + tmp = *mem + *smem; + asm volatile("" : "+r" (tmp)); + + fn(mem, smem, pagesize); +munmap: + munmap(mem, pagesize); + if (smem != MAP_FAILED) + munmap(smem, pagesize); +close: + fclose(file); +} + +static void run_with_memfd_hugetlb(non_anon_test_fn fn, const char *desc, + size_t hugetlbsize) +{ + int flags = MFD_HUGETLB; + char *mem, *smem, tmp; + int fd; + + ksft_print_msg("[RUN] %s ... with memfd hugetlb (%zu kB)\n", desc, + hugetlbsize / 1024); + + flags |= __builtin_ctzll(hugetlbsize) << MFD_HUGE_SHIFT; + + fd = memfd_create("test", flags); + if (fd < 0) { + ksft_test_result_skip("memfd_create() failed\n"); + return; + } + + /* File consists of a single page filled with zeroes. */ + if (fallocate(fd, 0, 0, hugetlbsize)) { + ksft_test_result_skip("need more free huge pages\n"); + goto close; + } + + /* Create a private mapping of the memfd. */ + mem = mmap(NULL, hugetlbsize, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, + 0); + if (mem == MAP_FAILED) { + ksft_test_result_skip("need more free huge pages\n"); + goto close; + } + smem = mmap(NULL, hugetlbsize, PROT_READ, MAP_SHARED, fd, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + goto munmap; + } + + /* Fault the page in. */ + tmp = *mem + *smem; + asm volatile("" : "+r" (tmp)); + + fn(mem, smem, hugetlbsize); +munmap: + munmap(mem, hugetlbsize); + if (mem != MAP_FAILED) + munmap(smem, hugetlbsize); +close: + close(fd); +} + +struct non_anon_test_case { + const char *desc; + non_anon_test_fn fn; +}; + +/* + * Test cases that target any pages in private mappings that are non anonymous: + * pages that may get shared via COW ndependent of fork(). This includes + * the shared zeropage(s), pagecache pages, ... + */ +static const struct non_anon_test_case non_anon_test_cases[] = { + /* + * Basic COW test without any GUP. If we miss to break COW, changes are + * visible via other private/shared mappings. + */ + { + "Basic COW", + test_cow, + }, +}; + +static void run_non_anon_test_case(struct non_anon_test_case const *test_case) +{ + int i; + + run_with_zeropage(test_case->fn, test_case->desc); + run_with_memfd(test_case->fn, test_case->desc); + run_with_tmpfile(test_case->fn, test_case->desc); + if (thpsize) + run_with_huge_zeropage(test_case->fn, test_case->desc); + for (i = 0; i < nr_hugetlbsizes; i++) + run_with_memfd_hugetlb(test_case->fn, test_case->desc, + hugetlbsizes[i]); +} + +static void run_non_anon_test_cases(void) +{ + int i; + + ksft_print_msg("[RUN] Non-anonymous memory tests in private mappings\n"); + + for (i = 0; i < ARRAY_SIZE(non_anon_test_cases); i++) + run_non_anon_test_case(&non_anon_test_cases[i]); +} + +static int tests_per_non_anon_test_case(void) +{ + int tests = 3 + nr_hugetlbsizes; + + if (thpsize) + tests += 1; + return tests; +} + int main(int argc, char **argv) { int err; @@ -1155,9 +1488,11 @@ int main(int argc, char **argv) pagesize = getpagesize(); detect_thpsize(); detect_hugetlbsizes(); + detect_huge_zeropage(); ksft_print_header(); - ksft_set_plan(ARRAY_SIZE(anon_test_cases) * tests_per_anon_test_case()); + ksft_set_plan(ARRAY_SIZE(anon_test_cases) * tests_per_anon_test_case() + + ARRAY_SIZE(non_anon_test_cases) * tests_per_non_anon_test_case()); gup_fd = open("/sys/kernel/debug/gup_test", O_RDWR); pagemap_fd = open("/proc/self/pagemap", O_RDONLY); @@ -1165,6 +1500,7 @@ int main(int argc, char **argv) ksft_exit_fail_msg("opening pagemap failed\n"); run_anon_test_cases(); + run_non_anon_test_cases(); err = ksft_get_fail_cnt(); if (err) -- cgit v1.2.3 From 97713a3abe338bb6c968e77264edbb68eb8d932a Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Wed, 16 Nov 2022 11:26:42 +0100 Subject: selftests/vm: cow: R/O long-term pinning reliability tests for non-anon pages Let's test whether R/O long-term pinning is reliable for non-anonymous memory: when R/O long-term pinning a page, the expectation is that we break COW early before pinning, such that actual write access via the page tables won't break COW later and end up replacing the R/O-pinned page in the page table. Consequently, R/O long-term pinning in private mappings would only target exclusive anonymous pages. For now, all tests fail: # [RUN] R/O longterm GUP pin ... with shared zeropage not ok 151 Longterm R/O pin is reliable # [RUN] R/O longterm GUP pin ... with memfd not ok 152 Longterm R/O pin is reliable # [RUN] R/O longterm GUP pin ... with tmpfile not ok 153 Longterm R/O pin is reliable # [RUN] R/O longterm GUP pin ... with huge zeropage not ok 154 Longterm R/O pin is reliable # [RUN] R/O longterm GUP pin ... with memfd hugetlb (2048 kB) not ok 155 Longterm R/O pin is reliable # [RUN] R/O longterm GUP pin ... with memfd hugetlb (1048576 kB) not ok 156 Longterm R/O pin is reliable # [RUN] R/O longterm GUP-fast pin ... with shared zeropage not ok 157 Longterm R/O pin is reliable # [RUN] R/O longterm GUP-fast pin ... with memfd not ok 158 Longterm R/O pin is reliable # [RUN] R/O longterm GUP-fast pin ... with tmpfile not ok 159 Longterm R/O pin is reliable # [RUN] R/O longterm GUP-fast pin ... with huge zeropage not ok 160 Longterm R/O pin is reliable # [RUN] R/O longterm GUP-fast pin ... with memfd hugetlb (2048 kB) not ok 161 Longterm R/O pin is reliable # [RUN] R/O longterm GUP-fast pin ... with memfd hugetlb (1048576 kB) not ok 162 Longterm R/O pin is reliable Link: https://lkml.kernel.org/r/20221116102659.70287-4-david@redhat.com Signed-off-by: David Hildenbrand Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/cow.c | 28 +++++++++++++++++++++++++++- 1 file changed, 27 insertions(+), 1 deletion(-) (limited to 'tools') diff --git a/tools/testing/selftests/vm/cow.c b/tools/testing/selftests/vm/cow.c index fb07bd44529c..73e05b52c49e 100644 --- a/tools/testing/selftests/vm/cow.c +++ b/tools/testing/selftests/vm/cow.c @@ -561,6 +561,7 @@ static void test_iouring_fork(char *mem, size_t size) #endif /* LOCAL_CONFIG_HAVE_LIBURING */ enum ro_pin_test { + RO_PIN_TEST, RO_PIN_TEST_SHARED, RO_PIN_TEST_PREVIOUSLY_SHARED, RO_PIN_TEST_RO_EXCLUSIVE, @@ -593,6 +594,8 @@ static void do_test_ro_pin(char *mem, size_t size, enum ro_pin_test test, } switch (test) { + case RO_PIN_TEST: + break; case RO_PIN_TEST_SHARED: case RO_PIN_TEST_PREVIOUSLY_SHARED: /* @@ -1193,6 +1196,16 @@ static void test_cow(char *mem, const char *smem, size_t size) free(old); } +static void test_ro_pin(char *mem, const char *smem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST, false); +} + +static void test_ro_fast_pin(char *mem, const char *smem, size_t size) +{ + do_test_ro_pin(mem, size, RO_PIN_TEST, true); +} + static void run_with_zeropage(non_anon_test_fn fn, const char *desc) { char *mem, *smem, tmp; @@ -1433,7 +1446,7 @@ struct non_anon_test_case { }; /* - * Test cases that target any pages in private mappings that are non anonymous: + * Test cases that target any pages in private mappings that are not anonymous: * pages that may get shared via COW ndependent of fork(). This includes * the shared zeropage(s), pagecache pages, ... */ @@ -1446,6 +1459,19 @@ static const struct non_anon_test_case non_anon_test_cases[] = { "Basic COW", test_cow, }, + /* + * Take a R/O longterm pin. When modifying the page via the page table, + * the page content change must be visible via the pin. + */ + { + "R/O longterm GUP pin", + test_ro_pin, + }, + /* Same as above, but using GUP-fast. */ + { + "R/O longterm GUP-fast pin", + test_ro_fast_pin, + }, }; static void run_non_anon_test_case(struct non_anon_test_case const *test_case) -- cgit v1.2.3 From 91a99f1d1248bdde674b66e20ac472ec76f6a202 Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Thu, 17 Nov 2022 16:29:15 -0500 Subject: selftests/vm: use memfd for hugepage-mmap test This test was overlooked with a hard-coded mntpoint path in test when we're removing the hugetlb mntpoint in commit 0796c7b8be84. Fix it up so the test can keep running. Link: https://lkml.kernel.org/r/Y3aojfUC2nSwbCzB@x1n Fixes: 0796c7b8be84 ("selftests/vm: drop mnt point for hugetlb in run_vmtests.sh") Signed-off-by: Peter Xu Reported-by: Joel Savitz Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/hugepage-mmap.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/vm/hugepage-mmap.c b/tools/testing/selftests/vm/hugepage-mmap.c index 93f9e7b81331..955ef87f382c 100644 --- a/tools/testing/selftests/vm/hugepage-mmap.c +++ b/tools/testing/selftests/vm/hugepage-mmap.c @@ -16,14 +16,13 @@ * range. * Other architectures, such as ppc64, i386 or x86_64 are not so constrained. */ - +#define _GNU_SOURCE #include #include #include #include #include -#define FILE_NAME "huge/hugepagefile" #define LENGTH (256UL*1024*1024) #define PROTECTION (PROT_READ | PROT_WRITE) @@ -67,16 +66,16 @@ int main(void) void *addr; int fd, ret; - fd = open(FILE_NAME, O_CREAT | O_RDWR, 0755); + fd = memfd_create("hugepage-mmap", MFD_HUGETLB); if (fd < 0) { - perror("Open failed"); + perror("memfd_create() failed"); exit(1); } addr = mmap(ADDR, LENGTH, PROTECTION, FLAGS, fd, 0); if (addr == MAP_FAILED) { perror("mmap"); - unlink(FILE_NAME); + close(fd); exit(1); } @@ -87,7 +86,6 @@ int main(void) munmap(addr, LENGTH); close(fd); - unlink(FILE_NAME); return ret; } -- cgit v1.2.3 From 85463321e726fe59873bbc21f2f480747810aef8 Mon Sep 17 00:00:00 2001 From: Joel Savitz Date: Tue, 18 Oct 2022 19:12:22 -0400 Subject: selftests/vm: enable running select groups of tests Our memory management kernel CI testing at Red Hat uses the VM selftests and we have run into two problems: First, our LTP tests overlap with the VM selftests. We want to avoid unhelpful redundancy in our testing practices. Second, we have observed the current run_vmtests.sh to report overall failure/ambiguous results in the case that a machine lacks the necessary hardware to perform one or more of the tests. E.g. ksm tests that require more than one numa node. We want to be able to run the vm selftests suitable to particular hardware. Add the ability to run one or more groups of vm tests via run_vmtests.sh instead of simply all-or-none in order to solve these problems. Preserve existing default behavior of running all tests when the script is invoked with no arguments. Documentation of test groups is included in the patch as follows: # ./run_vmtests.sh [ -h || --help ] usage: ./tools/testing/selftests/vm/run_vmtests.sh [ -h | -t ""] -t: specify specific categories to tests to run -h: display this message The default behavior is to run all tests. Alternatively, specific groups tests can be run by passing a string to the -t argument containing one or more of the following categories separated by spaces: - mmap tests for mmap(2) - gup_test tests for gup using gup_test interface - userfaultfd tests for userfaultfd(2) - compaction a test for the patch "Allow compaction of unevictable pages" - mlock tests for mlock(2) - mremap tests for mremap(2) - hugevm tests for very large virtual address space - vmalloc vmalloc smoke tests - hmm hmm smoke tests - madv_populate test memadvise(2) MADV_POPULATE_{READ,WRITE} options - memfd_secret test memfd_secret(2) - process_mrelease test process_mrelease(2) - ksm ksm tests that do not require >=2 NUMA nodes - ksm_numa ksm tests that require >=2 NUMA nodes - pkey memory protection key tests - soft_dirty test soft dirty page bit semantics - anon_cow test anonymous copy-on-write semantics example: ./run_vmtests.sh -t "hmm mmap ksm" Link: https://lkml.kernel.org/r/20221018231222.1884715-1-jsavitz@redhat.com Signed-off-by: Joel Savitz Cc: Joel Savitz Cc: Nico Pache Cc: Shuah Khan Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/run_vmtests.sh | 207 +++++++++++++++++++++--------- 1 file changed, 144 insertions(+), 63 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/vm/run_vmtests.sh b/tools/testing/selftests/vm/run_vmtests.sh index 54d7a822c2ce..e26661feacf5 100755 --- a/tools/testing/selftests/vm/run_vmtests.sh +++ b/tools/testing/selftests/vm/run_vmtests.sh @@ -1,13 +1,88 @@ #!/bin/bash # SPDX-License-Identifier: GPL-2.0 -#please run as root +# Please run as root # Kselftest framework requirement - SKIP code is 4. ksft_skip=4 exitcode=0 -#get huge pagesize and freepages from /proc/meminfo +usage() { + cat <"] + -t: specify specific categories to tests to run + -h: display this message + +The default behavior is to run all tests. + +Alternatively, specific groups tests can be run by passing a string +to the -t argument containing one or more of the following categories +separated by spaces: +- mmap + tests for mmap(2) +- gup_test + tests for gup using gup_test interface +- userfaultfd + tests for userfaultfd(2) +- compaction + a test for the patch "Allow compaction of unevictable pages" +- mlock + tests for mlock(2) +- mremap + tests for mremap(2) +- hugevm + tests for very large virtual address space +- vmalloc + vmalloc smoke tests +- hmm + hmm smoke tests +- madv_populate + test memadvise(2) MADV_POPULATE_{READ,WRITE} options +- memfd_secret + test memfd_secret(2) +- process_mrelease + test process_mrelease(2) +- ksm + ksm tests that do not require >=2 NUMA nodes +- ksm_numa + ksm tests that require >=2 NUMA nodes +- pkey + memory protection key tests +- soft_dirty + test soft dirty page bit semantics +- cow + test copy-on-write semantics +example: ./run_vmtests.sh -t "hmm mmap ksm" +EOF + exit 0 +} + + +while getopts "ht:" OPT; do + case ${OPT} in + "h") usage ;; + "t") VM_SELFTEST_ITEMS=${OPTARG} ;; + esac +done +shift $((OPTIND -1)) + +# default behavior: run all tests +VM_SELFTEST_ITEMS=${VM_SELFTEST_ITEMS:-default} + +test_selected() { + if [ "$VM_SELFTEST_ITEMS" == "default" ]; then + # If no VM_SELFTEST_ITEMS are specified, run all tests + return 0 + fi + # If test selected argument is one of the test items + if [[ " ${VM_SELFTEST_ITEMS[*]} " =~ " ${1} " ]]; then + return 0 + else + return 1 + fi +} + +# get huge pagesize and freepages from /proc/meminfo while read -r name size unit; do if [ "$name" = "HugePages_Free:" ]; then freepgs="$size" @@ -27,7 +102,7 @@ hpgsize_MB=$((hpgsize_KB / 1024)) half_ufd_size_MB=$((((nr_cpus * hpgsize_MB + 127) / 128) * 128)) needmem_KB=$((half_ufd_size_MB * 2 * 1024)) -#set proper nr_hugepages +# set proper nr_hugepages if [ -n "$freepgs" ] && [ -n "$hpgsize_KB" ]; then nr_hugepgs=$(cat /proc/sys/vm/nr_hugepages) needpgs=$((needmem_KB / hpgsize_KB)) @@ -56,136 +131,142 @@ else exit 1 fi -#filter 64bit architectures +# filter 64bit architectures ARCH64STR="arm64 ia64 mips64 parisc64 ppc64 ppc64le riscv64 s390x sh64 sparc64 x86_64" if [ -z "$ARCH" ]; then ARCH=$(uname -m 2>/dev/null | sed -e 's/aarch64.*/arm64/') fi VADDR64=0 -echo "$ARCH64STR" | grep "$ARCH" && VADDR64=1 +echo "$ARCH64STR" | grep "$ARCH" &>/dev/null && VADDR64=1 # Usage: run_test [test binary] [arbitrary test arguments...] run_test() { - local title="running $*" - local sep=$(echo -n "$title" | tr "[:graph:][:space:]" -) - printf "%s\n%s\n%s\n" "$sep" "$title" "$sep" - - "$@" - local ret=$? - if [ $ret -eq 0 ]; then - echo "[PASS]" - elif [ $ret -eq $ksft_skip ]; then - echo "[SKIP]" - exitcode=$ksft_skip - else - echo "[FAIL]" - exitcode=1 - fi + if test_selected ${CATEGORY}; then + local title="running $*" + local sep=$(echo -n "$title" | tr "[:graph:][:space:]" -) + printf "%s\n%s\n%s\n" "$sep" "$title" "$sep" + + "$@" + local ret=$? + if [ $ret -eq 0 ]; then + echo "[PASS]" + elif [ $ret -eq $ksft_skip ]; then + echo "[SKIP]" + exitcode=$ksft_skip + else + echo "[FAIL]" + exitcode=1 + fi + fi # test_selected } -run_test ./hugepage-mmap +CATEGORY="hugetlb" run_test ./hugepage-mmap shmmax=$(cat /proc/sys/kernel/shmmax) shmall=$(cat /proc/sys/kernel/shmall) echo 268435456 > /proc/sys/kernel/shmmax echo 4194304 > /proc/sys/kernel/shmall -run_test ./hugepage-shm +CATEGORY="hugetlb" run_test ./hugepage-shm echo "$shmmax" > /proc/sys/kernel/shmmax echo "$shmall" > /proc/sys/kernel/shmall -run_test ./map_hugetlb -run_test ./hugepage-mremap -run_test ./hugepage-vmemmap -run_test ./hugetlb-madvise +CATEGORY="hugetlb" run_test ./map_hugetlb +CATEGORY="hugetlb" run_test ./hugepage-mremap +CATEGORY="hugetlb" run_test ./hugepage-vmemmap +CATEGORY="hugetlb" run_test ./hugetlb-madvise -echo "NOTE: The above hugetlb tests provide minimal coverage. Use" -echo " https://github.com/libhugetlbfs/libhugetlbfs.git for" -echo " hugetlb regression testing." +if test_selected "hugetlb"; then + echo "NOTE: These hugetlb tests provide minimal coverage. Use" + echo " https://github.com/libhugetlbfs/libhugetlbfs.git for" + echo " hugetlb regression testing." +fi -run_test ./map_fixed_noreplace +CATEGORY="mmap" run_test ./map_fixed_noreplace # get_user_pages_fast() benchmark -run_test ./gup_test -u +CATEGORY="gup_test" run_test ./gup_test -u # pin_user_pages_fast() benchmark -run_test ./gup_test -a +CATEGORY="gup_test" run_test ./gup_test -a # Dump pages 0, 19, and 4096, using pin_user_pages: -run_test ./gup_test -ct -F 0x1 0 19 0x1000 +CATEGORY="gup_test" run_test ./gup_test -ct -F 0x1 0 19 0x1000 uffd_mods=("" ":dev") for mod in "${uffd_mods[@]}"; do - run_test ./userfaultfd anon${mod} 20 16 + CATEGORY="userfaultfd" run_test ./userfaultfd anon${mod} 20 16 # Hugetlb tests require source and destination huge pages. Pass in half # the size ($half_ufd_size_MB), which is used for *each*. - run_test ./userfaultfd hugetlb${mod} "$half_ufd_size_MB" 32 - run_test ./userfaultfd hugetlb_shared${mod} "$half_ufd_size_MB" 32 - run_test ./userfaultfd shmem${mod} 20 16 + CATEGORY="userfaultfd" run_test ./userfaultfd hugetlb${mod} "$half_ufd_size_MB" 32 + CATEGORY="userfaultfd" run_test ./userfaultfd hugetlb_shared${mod} "$half_ufd_size_MB" 32 + CATEGORY="userfaultfd" run_test ./userfaultfd shmem${mod} 20 16 done #cleanup echo "$nr_hugepgs" > /proc/sys/vm/nr_hugepages -run_test ./compaction_test +CATEGORY="compaction" run_test ./compaction_test -run_test sudo -u nobody ./on-fault-limit +CATEGORY="mlock" run_test sudo -u nobody ./on-fault-limit -run_test ./map_populate +CATEGORY="mmap" run_test ./map_populate -run_test ./mlock-random-test +CATEGORY="mlock" run_test ./mlock-random-test -run_test ./mlock2-tests +CATEGORY="mlock" run_test ./mlock2-tests -run_test ./mrelease_test +CATEGORY="process_mrelease" run_test ./mrelease_test -run_test ./mremap_test +CATEGORY="mremap" run_test ./mremap_test -run_test ./thuge-gen +CATEGORY="hugetlb" run_test ./thuge-gen if [ $VADDR64 -ne 0 ]; then - run_test ./virtual_address_range + CATEGORY="hugevm" run_test ./virtual_address_range # virtual address 128TB switch test - run_test ./va_128TBswitch.sh + CATEGORY="hugevm" run_test ./va_128TBswitch.sh fi # VADDR64 # vmalloc stability smoke test -run_test ./test_vmalloc.sh smoke +CATEGORY="vmalloc" run_test ./test_vmalloc.sh smoke -run_test ./mremap_dontunmap +CATEGORY="mremap" run_test ./mremap_dontunmap -run_test ./test_hmm.sh smoke +CATEGORY="hmm" run_test ./test_hmm.sh smoke # MADV_POPULATE_READ and MADV_POPULATE_WRITE tests -run_test ./madv_populate +CATEGORY="madv_populate" run_test ./madv_populate -run_test ./memfd_secret +CATEGORY="memfd_secret" run_test ./memfd_secret # KSM MADV_MERGEABLE test with 10 identical pages -run_test ./ksm_tests -M -p 10 +CATEGORY="ksm" run_test ./ksm_tests -M -p 10 # KSM unmerge test -run_test ./ksm_tests -U +CATEGORY="ksm" run_test ./ksm_tests -U # KSM test with 10 zero pages and use_zero_pages = 0 -run_test ./ksm_tests -Z -p 10 -z 0 +CATEGORY="ksm" run_test ./ksm_tests -Z -p 10 -z 0 # KSM test with 10 zero pages and use_zero_pages = 1 -run_test ./ksm_tests -Z -p 10 -z 1 +CATEGORY="ksm" run_test ./ksm_tests -Z -p 10 -z 1 # KSM test with 2 NUMA nodes and merge_across_nodes = 1 -run_test ./ksm_tests -N -m 1 +CATEGORY="ksm_numa" run_test ./ksm_tests -N -m 1 # KSM test with 2 NUMA nodes and merge_across_nodes = 0 -run_test ./ksm_tests -N -m 0 +CATEGORY="ksm_numa" run_test ./ksm_tests -N -m 0 + +CATEGORY="ksm" run_test ./ksm_functional_tests # protection_keys tests if [ -x ./protection_keys_32 ] then - run_test ./protection_keys_32 + CATEGORY="pkey" run_test ./protection_keys_32 fi if [ -x ./protection_keys_64 ] then - run_test ./protection_keys_64 + CATEGORY="pkey" run_test ./protection_keys_64 fi -run_test ./soft-dirty +CATEGORY="soft_dirty" run_test ./soft-dirty -# COW tests for anonymous memory -run_test ./cow +# COW tests +CATEGORY="cow" run_test ./cow exit $exitcode -- cgit v1.2.3 From 93fb70aa5904c2577fab8100fa990ecfa4f5b4c7 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Fri, 21 Oct 2022 12:11:36 +0200 Subject: selftests/vm: add KSM unmerge tests Patch series "mm/ksm: break_ksm() cleanups and fixes", v2. This series cleans up and fixes break_ksm(). In summary, we no longer use fake write faults to break COW but instead FAULT_FLAG_UNSHARE. Further, we move away from using follow_page() --- that we can hopefully remove completely at one point --- and use new walk_page_range_vma() instead. Fortunately, we can get rid of VM_FAULT_WRITE and FOLL_MIGRATION in common code now. Extend the existing ksm tests by an unmerge benchmark, and a some new unmerge tests. Also, add a selftest to measure MADV_UNMERGEABLE performance. In my setup (AMD Ryzen 9 3900X), running the KSM selftest to test unmerge performance on 2 GiB (taskset 0x8 ./ksm_tests -D -s 2048), this results in a performance degradation of ~6% -- 7% (old: ~5250 MiB/s, new: ~4900 MiB/s). I don't think we particularly care for now, but it's good to be aware of the implication. This patch (of 9): Let's add three unmerge tests (MADV_UNMERGEABLE unmerging all pages in the range). test_unmerge(): basic unmerge tests test_unmerge_discarded(): have some pte_none() entries in the range test_unmerge_uffd_wp(): protect the merged pages using uffd-wp ksm_tests.c currently contains a mixture of benchmarks and tests, whereby each test is carried out by executing the ksm_tests binary with specific parameters. Let's add new ksm_functional_tests.c that performs multiple, smaller functional tests all at once. Link: https://lkml.kernel.org/r/20221021101141.84170-1-david@redhat.com Link: https://lkml.kernel.org/r/20221021101141.84170-5-david@redhat.com Signed-off-by: David Hildenbrand Cc: Andrea Arcangeli Cc: Hugh Dickins Cc: Jason Gunthorpe Cc: John Hubbard Cc: Matthew Wilcox (Oracle) Cc: Peter Xu Cc: Shuah Khan Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/Makefile | 2 + tools/testing/selftests/vm/ksm_functional_tests.c | 279 ++++++++++++++++++++++ tools/testing/selftests/vm/run_vmtests.sh | 2 + tools/testing/selftests/vm/vm_util.c | 10 + tools/testing/selftests/vm/vm_util.h | 1 + 5 files changed, 294 insertions(+) create mode 100644 tools/testing/selftests/vm/ksm_functional_tests.c (limited to 'tools') diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index a4d764efd6e3..89c14e41bd43 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -55,6 +55,7 @@ TEST_GEN_FILES += userfaultfd TEST_GEN_PROGS += soft-dirty TEST_GEN_PROGS += split_huge_page_test TEST_GEN_FILES += ksm_tests +TEST_GEN_PROGS += ksm_functional_tests ifeq ($(MACHINE),x86_64) CAN_BUILD_I386 := $(shell ./../x86/check_cc.sh "$(CC)" ../x86/trivial_32bit_program.c -m32) @@ -100,6 +101,7 @@ include ../lib.mk $(OUTPUT)/cow: vm_util.c $(OUTPUT)/khugepaged: vm_util.c +$(OUTPUT)/ksm_functional_tests: vm_util.c $(OUTPUT)/madv_populate: vm_util.c $(OUTPUT)/soft-dirty: vm_util.c $(OUTPUT)/split_huge_page_test: vm_util.c diff --git a/tools/testing/selftests/vm/ksm_functional_tests.c b/tools/testing/selftests/vm/ksm_functional_tests.c new file mode 100644 index 000000000000..96644be68962 --- /dev/null +++ b/tools/testing/selftests/vm/ksm_functional_tests.c @@ -0,0 +1,279 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * KSM functional tests + * + * Copyright 2022, Red Hat, Inc. + * + * Author(s): David Hildenbrand + */ +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "../kselftest.h" +#include "vm_util.h" + +#define KiB 1024u +#define MiB (1024 * KiB) + +static int ksm_fd; +static int ksm_full_scans_fd; +static int pagemap_fd; +static size_t pagesize; + +static bool range_maps_duplicates(char *addr, unsigned long size) +{ + unsigned long offs_a, offs_b, pfn_a, pfn_b; + + /* + * There is no easy way to check if there are KSM pages mapped into + * this range. We only check that the range does not map the same PFN + * twice by comaring each pair of mapped pages. + */ + for (offs_a = 0; offs_a < size; offs_a += pagesize) { + pfn_a = pagemap_get_pfn(pagemap_fd, addr + offs_a); + /* Page not present or PFN not exposed by the kernel. */ + if (pfn_a == -1ull || !pfn_a) + continue; + + for (offs_b = offs_a + pagesize; offs_b < size; + offs_b += pagesize) { + pfn_b = pagemap_get_pfn(pagemap_fd, addr + offs_b); + if (pfn_b == -1ull || !pfn_b) + continue; + if (pfn_a == pfn_b) + return true; + } + } + return false; +} + +static long ksm_get_full_scans(void) +{ + char buf[10]; + ssize_t ret; + + ret = pread(ksm_full_scans_fd, buf, sizeof(buf) - 1, 0); + if (ret <= 0) + return -errno; + buf[ret] = 0; + + return strtol(buf, NULL, 10); +} + +static int ksm_merge(void) +{ + long start_scans, end_scans; + + /* Wait for two full scans such that any possible merging happened. */ + start_scans = ksm_get_full_scans(); + if (start_scans < 0) + return start_scans; + if (write(ksm_fd, "1", 1) != 1) + return -errno; + do { + end_scans = ksm_get_full_scans(); + if (end_scans < 0) + return end_scans; + } while (end_scans < start_scans + 2); + + return 0; +} + +static char *mmap_and_merge_range(char val, unsigned long size) +{ + char *map; + + map = mmap(NULL, size, PROT_READ|PROT_WRITE, + MAP_PRIVATE|MAP_ANON, -1, 0); + if (map == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + return MAP_FAILED; + } + + /* Don't use THP. Ignore if THP are not around on a kernel. */ + if (madvise(map, size, MADV_NOHUGEPAGE) && errno != EINVAL) { + ksft_test_result_fail("MADV_NOHUGEPAGE failed\n"); + goto unmap; + } + + /* Make sure each page contains the same values to merge them. */ + memset(map, val, size); + if (madvise(map, size, MADV_MERGEABLE)) { + ksft_test_result_fail("MADV_MERGEABLE failed\n"); + goto unmap; + } + + /* Run KSM to trigger merging and wait. */ + if (ksm_merge()) { + ksft_test_result_fail("Running KSM failed\n"); + goto unmap; + } + return map; +unmap: + munmap(map, size); + return MAP_FAILED; +} + +static void test_unmerge(void) +{ + const unsigned int size = 2 * MiB; + char *map; + + ksft_print_msg("[RUN] %s\n", __func__); + + map = mmap_and_merge_range(0xcf, size); + if (map == MAP_FAILED) + return; + + if (madvise(map, size, MADV_UNMERGEABLE)) { + ksft_test_result_fail("MADV_UNMERGEABLE failed\n"); + goto unmap; + } + + ksft_test_result(!range_maps_duplicates(map, size), + "Pages were unmerged\n"); +unmap: + munmap(map, size); +} + +static void test_unmerge_discarded(void) +{ + const unsigned int size = 2 * MiB; + char *map; + + ksft_print_msg("[RUN] %s\n", __func__); + + map = mmap_and_merge_range(0xcf, size); + if (map == MAP_FAILED) + return; + + /* Discard half of all mapped pages so we have pte_none() entries. */ + if (madvise(map, size / 2, MADV_DONTNEED)) { + ksft_test_result_fail("MADV_DONTNEED failed\n"); + goto unmap; + } + + if (madvise(map, size, MADV_UNMERGEABLE)) { + ksft_test_result_fail("MADV_UNMERGEABLE failed\n"); + goto unmap; + } + + ksft_test_result(!range_maps_duplicates(map, size), + "Pages were unmerged\n"); +unmap: + munmap(map, size); +} + +#ifdef __NR_userfaultfd +static void test_unmerge_uffd_wp(void) +{ + struct uffdio_writeprotect uffd_writeprotect; + struct uffdio_register uffdio_register; + const unsigned int size = 2 * MiB; + struct uffdio_api uffdio_api; + char *map; + int uffd; + + ksft_print_msg("[RUN] %s\n", __func__); + + map = mmap_and_merge_range(0xcf, size); + if (map == MAP_FAILED) + return; + + /* See if UFFD is around. */ + uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK); + if (uffd < 0) { + ksft_test_result_skip("__NR_userfaultfd failed\n"); + goto unmap; + } + + /* See if UFFD-WP is around. */ + uffdio_api.api = UFFD_API; + uffdio_api.features = UFFD_FEATURE_PAGEFAULT_FLAG_WP; + if (ioctl(uffd, UFFDIO_API, &uffdio_api) < 0) { + ksft_test_result_fail("UFFDIO_API failed\n"); + goto close_uffd; + } + if (!(uffdio_api.features & UFFD_FEATURE_PAGEFAULT_FLAG_WP)) { + ksft_test_result_skip("UFFD_FEATURE_PAGEFAULT_FLAG_WP not available\n"); + goto close_uffd; + } + + /* Register UFFD-WP, no need for an actual handler. */ + uffdio_register.range.start = (unsigned long) map; + uffdio_register.range.len = size; + uffdio_register.mode = UFFDIO_REGISTER_MODE_WP; + if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register) < 0) { + ksft_test_result_fail("UFFDIO_REGISTER_MODE_WP failed\n"); + goto close_uffd; + } + + /* Write-protect the range using UFFD-WP. */ + uffd_writeprotect.range.start = (unsigned long) map; + uffd_writeprotect.range.len = size; + uffd_writeprotect.mode = UFFDIO_WRITEPROTECT_MODE_WP; + if (ioctl(uffd, UFFDIO_WRITEPROTECT, &uffd_writeprotect)) { + ksft_test_result_fail("UFFDIO_WRITEPROTECT failed\n"); + goto close_uffd; + } + + if (madvise(map, size, MADV_UNMERGEABLE)) { + ksft_test_result_fail("MADV_UNMERGEABLE failed\n"); + goto close_uffd; + } + + ksft_test_result(!range_maps_duplicates(map, size), + "Pages were unmerged\n"); +close_uffd: + close(uffd); +unmap: + munmap(map, size); +} +#endif + +int main(int argc, char **argv) +{ + unsigned int tests = 2; + int err; + +#ifdef __NR_userfaultfd + tests++; +#endif + + ksft_print_header(); + ksft_set_plan(tests); + + pagesize = getpagesize(); + + ksm_fd = open("/sys/kernel/mm/ksm/run", O_RDWR); + if (ksm_fd < 0) + ksft_exit_skip("open(\"/sys/kernel/mm/ksm/run\") failed\n"); + ksm_full_scans_fd = open("/sys/kernel/mm/ksm/full_scans", O_RDONLY); + if (ksm_full_scans_fd < 0) + ksft_exit_skip("open(\"/sys/kernel/mm/ksm/full_scans\") failed\n"); + pagemap_fd = open("/proc/self/pagemap", O_RDONLY); + if (pagemap_fd < 0) + ksft_exit_skip("open(\"/proc/self/pagemap\") failed\n"); + + test_unmerge(); + test_unmerge_discarded(); +#ifdef __NR_userfaultfd + test_unmerge_uffd_wp(); +#endif + + err = ksft_get_fail_cnt(); + if (err) + ksft_exit_fail_msg("%d out of %d tests failed\n", + err, ksft_test_num()); + return ksft_exit_pass(); +} diff --git a/tools/testing/selftests/vm/run_vmtests.sh b/tools/testing/selftests/vm/run_vmtests.sh index e26661feacf5..8984e0bb58c7 100755 --- a/tools/testing/selftests/vm/run_vmtests.sh +++ b/tools/testing/selftests/vm/run_vmtests.sh @@ -253,6 +253,8 @@ CATEGORY="ksm_numa" run_test ./ksm_tests -N -m 0 CATEGORY="ksm" run_test ./ksm_functional_tests +run_test ./ksm_functional_tests + # protection_keys tests if [ -x ./protection_keys_32 ] then diff --git a/tools/testing/selftests/vm/vm_util.c b/tools/testing/selftests/vm/vm_util.c index 5bbf7641a0f0..710571902743 100644 --- a/tools/testing/selftests/vm/vm_util.c +++ b/tools/testing/selftests/vm/vm_util.c @@ -43,6 +43,16 @@ bool pagemap_is_populated(int fd, char *start) return entry & 0xc000000000000000ull; } +unsigned long pagemap_get_pfn(int fd, char *start) +{ + uint64_t entry = pagemap_get_entry(fd, start); + + /* If present (63th bit), PFN is at bit 0 -- 54. */ + if (entry & 0x8000000000000000ull) + return entry & 0x007fffffffffffffull; + return -1ull; +} + void clear_softdirty(void) { int ret; diff --git a/tools/testing/selftests/vm/vm_util.h b/tools/testing/selftests/vm/vm_util.h index 80d5a6ad413b..1995ee911ef2 100644 --- a/tools/testing/selftests/vm/vm_util.h +++ b/tools/testing/selftests/vm/vm_util.h @@ -6,6 +6,7 @@ uint64_t pagemap_get_entry(int fd, char *start); bool pagemap_is_softdirty(int fd, char *start); bool pagemap_is_swapped(int fd, char *start); bool pagemap_is_populated(int fd, char *start); +unsigned long pagemap_get_pfn(int fd, char *start); void clear_softdirty(void); bool check_for_pattern(FILE *fp, const char *pattern, char *buf, size_t len); uint64_t read_pmd_pagesize(void); -- cgit v1.2.3 From 5036880efdad976165c817dcb6a1c8c24fb16caa Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Fri, 21 Oct 2022 12:11:33 +0200 Subject: selftests/vm: add test to measure MADV_UNMERGEABLE performance Let's add a test to measure performance of KSM breaking not triggered via COW, but triggered by disabling KSM on an area filled with KSM pages via MADV_UNMERGEABLE. Link: https://lkml.kernel.org/r/20221021101141.84170-2-david@redhat.com Signed-off-by: David Hildenbrand Acked-by: Peter Xu Cc: Andrea Arcangeli Cc: Hugh Dickins Cc: Jason Gunthorpe Cc: John Hubbard Cc: Matthew Wilcox (Oracle) Cc: Shuah Khan Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/ksm_tests.c | 76 +++++++++++++++++++++++++++++++++- 1 file changed, 74 insertions(+), 2 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/vm/ksm_tests.c b/tools/testing/selftests/vm/ksm_tests.c index 0d85be2350fa..f9eb4d67e0dd 100644 --- a/tools/testing/selftests/vm/ksm_tests.c +++ b/tools/testing/selftests/vm/ksm_tests.c @@ -40,6 +40,7 @@ enum ksm_test_name { CHECK_KSM_NUMA_MERGE, KSM_MERGE_TIME, KSM_MERGE_TIME_HUGE_PAGES, + KSM_UNMERGE_TIME, KSM_COW_TIME }; @@ -108,7 +109,10 @@ static void print_help(void) " -P evaluate merging time and speed.\n" " For this test, the size of duplicated memory area (in MiB)\n" " must be provided using -s option\n" - " -H evaluate merging time and speed of area allocated mostly with huge pages\n" + " -H evaluate merging time and speed of area allocated mostly with huge pages\n" + " For this test, the size of duplicated memory area (in MiB)\n" + " must be provided using -s option\n" + " -D evaluate unmerging time and speed when disabling KSM.\n" " For this test, the size of duplicated memory area (in MiB)\n" " must be provided using -s option\n" " -C evaluate the time required to break COW of merged pages.\n\n"); @@ -188,6 +192,16 @@ static int ksm_merge_pages(void *addr, size_t size, struct timespec start_time, return 0; } +static int ksm_unmerge_pages(void *addr, size_t size, + struct timespec start_time, int timeout) +{ + if (madvise(addr, size, MADV_UNMERGEABLE)) { + perror("madvise"); + return 1; + } + return 0; +} + static bool assert_ksm_pages_count(long dupl_page_count) { unsigned long max_page_sharing, pages_sharing, pages_shared; @@ -560,6 +574,53 @@ err_out: return KSFT_FAIL; } +static int ksm_unmerge_time(int mapping, int prot, int timeout, size_t map_size) +{ + void *map_ptr; + struct timespec start_time, end_time; + unsigned long scan_time_ns; + + map_size *= MB; + + map_ptr = allocate_memory(NULL, prot, mapping, '*', map_size); + if (!map_ptr) + return KSFT_FAIL; + if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) { + perror("clock_gettime"); + goto err_out; + } + if (ksm_merge_pages(map_ptr, map_size, start_time, timeout)) + goto err_out; + + if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) { + perror("clock_gettime"); + goto err_out; + } + if (ksm_unmerge_pages(map_ptr, map_size, start_time, timeout)) + goto err_out; + if (clock_gettime(CLOCK_MONOTONIC_RAW, &end_time)) { + perror("clock_gettime"); + goto err_out; + } + + scan_time_ns = (end_time.tv_sec - start_time.tv_sec) * NSEC_PER_SEC + + (end_time.tv_nsec - start_time.tv_nsec); + + printf("Total size: %lu MiB\n", map_size / MB); + printf("Total time: %ld.%09ld s\n", scan_time_ns / NSEC_PER_SEC, + scan_time_ns % NSEC_PER_SEC); + printf("Average speed: %.3f MiB/s\n", (map_size / MB) / + ((double)scan_time_ns / NSEC_PER_SEC)); + + munmap(map_ptr, map_size); + return KSFT_PASS; + +err_out: + printf("Not OK\n"); + munmap(map_ptr, map_size); + return KSFT_FAIL; +} + static int ksm_cow_time(int mapping, int prot, int timeout, size_t page_size) { void *map_ptr; @@ -644,7 +705,7 @@ int main(int argc, char *argv[]) bool merge_across_nodes = KSM_MERGE_ACROSS_NODES_DEFAULT; long size_MB = 0; - while ((opt = getopt(argc, argv, "ha:p:l:z:m:s:MUZNPCH")) != -1) { + while ((opt = getopt(argc, argv, "ha:p:l:z:m:s:MUZNPCHD")) != -1) { switch (opt) { case 'a': prot = str_to_prot(optarg); @@ -701,6 +762,9 @@ int main(int argc, char *argv[]) case 'H': test_name = KSM_MERGE_TIME_HUGE_PAGES; break; + case 'D': + test_name = KSM_UNMERGE_TIME; + break; case 'C': test_name = KSM_COW_TIME; break; @@ -762,6 +826,14 @@ int main(int argc, char *argv[]) ret = ksm_merge_hugepages_time(MAP_PRIVATE | MAP_ANONYMOUS, prot, ksm_scan_limit_sec, size_MB); break; + case KSM_UNMERGE_TIME: + if (size_MB == 0) { + printf("Option '-s' is required.\n"); + return KSFT_FAIL; + } + ret = ksm_unmerge_time(MAP_PRIVATE | MAP_ANONYMOUS, prot, + ksm_scan_limit_sec, size_MB); + break; case KSM_COW_TIME: ret = ksm_cow_time(MAP_PRIVATE | MAP_ANONYMOUS, prot, ksm_scan_limit_sec, page_size); -- cgit v1.2.3 From 0b7623bdf89b9f6d320784e929acb78291aaf5f6 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Thu, 1 Dec 2022 17:08:34 +0000 Subject: selftests/damon: test removed scheme sysfs dir access bug A DAMON sysfs user could start DAMON with a scheme, remove the sysfs directory for the scheme, and then ask stats or schemes tried regions update. The related logic were not aware of the already removed directory situation, so it was able to results in invalid memory accesses. The fix has made with commit 8468b486612c ("mm/damon/sysfs-schemes: skip stats update if the scheme directory is removed"), though. Add a selftest to prevent such kinds of bugs from being introduced again. Link: https://lkml.kernel.org/r/20221201170834.62823-1-sj@kernel.org Signed-off-by: SeongJae Park Cc: Shuah Khan Signed-off-by: Andrew Morton --- tools/testing/selftests/damon/Makefile | 2 +- .../damon/sysfs_update_removed_scheme_dir.sh | 58 ++++++++++++++++++++++ 2 files changed, 59 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/damon/sysfs_update_removed_scheme_dir.sh (limited to 'tools') diff --git a/tools/testing/selftests/damon/Makefile b/tools/testing/selftests/damon/Makefile index 838a8e49f77b..b71247ba7196 100644 --- a/tools/testing/selftests/damon/Makefile +++ b/tools/testing/selftests/damon/Makefile @@ -8,7 +8,7 @@ TEST_PROGS = debugfs_attrs.sh debugfs_schemes.sh debugfs_target_ids.sh TEST_PROGS += debugfs_empty_targets.sh debugfs_huge_count_read_write.sh TEST_PROGS += debugfs_duplicate_context_creation.sh TEST_PROGS += debugfs_rm_non_contexts.sh -TEST_PROGS += sysfs.sh +TEST_PROGS += sysfs.sh sysfs_update_removed_scheme_dir.sh TEST_PROGS += reclaim.sh lru_sort.sh include ../lib.mk diff --git a/tools/testing/selftests/damon/sysfs_update_removed_scheme_dir.sh b/tools/testing/selftests/damon/sysfs_update_removed_scheme_dir.sh new file mode 100644 index 000000000000..ade35576e748 --- /dev/null +++ b/tools/testing/selftests/damon/sysfs_update_removed_scheme_dir.sh @@ -0,0 +1,58 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 + +# Kselftest framework requirement - SKIP code is 4. +ksft_skip=4 + +if [ $EUID -ne 0 ] +then + echo "Run as root" + exit $ksft_skip +fi + +damon_sysfs="/sys/kernel/mm/damon/admin" +if [ ! -d "$damon_sysfs" ] +then + echo "damon sysfs not found" + exit $ksft_skip +fi + +# clear log +dmesg -C + +# start DAMON with a scheme +echo 1 > "$damon_sysfs/kdamonds/nr_kdamonds" +echo 1 > "$damon_sysfs/kdamonds/0/contexts/nr_contexts" +echo "vaddr" > "$damon_sysfs/kdamonds/0/contexts/0/operations" +echo 1 > "$damon_sysfs/kdamonds/0/contexts/0/targets/nr_targets" +echo $$ > "$damon_sysfs/kdamonds/0/contexts/0/targets/0/pid_target" +echo 1 > "$damon_sysfs/kdamonds/0/contexts/0/schemes/nr_schemes" +scheme_dir="$damon_sysfs/kdamonds/0/contexts/0/schemes/0" +echo 4096000 > "$scheme_dir/access_pattern/sz/max" +echo 20 > "$scheme_dir/access_pattern/nr_accesses/max" +echo 1024 > "$scheme_dir/access_pattern/age/max" +echo "on" > "$damon_sysfs/kdamonds/0/state" +sleep 0.3 + +# remove scheme sysfs dir +echo 0 > "$damon_sysfs/kdamonds/0/contexts/0/schemes/nr_schemes" + +# try to update stat of already removed scheme sysfs dir +echo "update_schemes_stats" > "$damon_sysfs/kdamonds/0/state" +if dmesg | grep -q BUG +then + echo "update_schemes_stats triggers a kernel bug" + dmesg + exit 1 +fi + +# try to update tried regions of already removed scheme sysfs dir +echo "update_schemes_tried_regions" > "$damon_sysfs/kdamonds/0/state" +if dmesg | grep -q BUG +then + echo "update_schemes_tried_regions triggers a kernel bug" + dmesg + exit 1 +fi + +echo "off" > "$damon_sysfs/kdamonds/0/state" -- cgit v1.2.3 From e5d64edac64531375716fabe35c9e0a502ca2894 Mon Sep 17 00:00:00 2001 From: Yosry Ahmed Date: Fri, 2 Dec 2022 03:15:11 +0000 Subject: selftests: cgroup: refactor proactive reclaim code to reclaim_until() Refactor the code that drives writing to memory.reclaim (retrying, error handling, etc) from test_memcg_reclaim() to a helper called reclaim_until(), which proactively reclaims from a memcg until its usage reaches a certain value. While we are at it, refactor and simplify the reclaim loop. This will be used in a following patch in another test. Link: https://lkml.kernel.org/r/20221202031512.1365483-3-yosryahmed@google.com Signed-off-by: Yosry Ahmed Suggested-by: Roman Gushchin Reviewed-by: Roman Gushchin Cc: Chris Down Cc: David Rientjes Cc: Johannes Weiner Cc: Matthew Wilcox Cc: Michal Hocko Cc: Muchun Song Cc: Shakeel Butt Cc: Tejun Heo Cc: Vasily Averin Cc: Vlastimil Babka Cc: Yu Zhao Signed-off-by: Andrew Morton --- tools/testing/selftests/cgroup/test_memcontrol.c | 80 +++++++++++++----------- 1 file changed, 44 insertions(+), 36 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/cgroup/test_memcontrol.c b/tools/testing/selftests/cgroup/test_memcontrol.c index 8833359556f3..a8f4700353a4 100644 --- a/tools/testing/selftests/cgroup/test_memcontrol.c +++ b/tools/testing/selftests/cgroup/test_memcontrol.c @@ -645,6 +645,48 @@ cleanup: return ret; } +/* + * Reclaim from @memcg until usage reaches @goal by writing to + * memory.reclaim. + * + * This function will return false if the usage is already below the + * goal. + * + * This function assumes that writing to memory.reclaim is the only + * source of change in memory.current (no concurrent allocations or + * reclaim). + * + * This function makes sure memory.reclaim is sane. It will return + * false if memory.reclaim's error codes do not make sense, even if + * the usage goal was satisfied. + */ +static bool reclaim_until(const char *memcg, long goal) +{ + char buf[64]; + int retries, err; + long current, to_reclaim; + bool reclaimed = false; + + for (retries = 5; retries > 0; retries--) { + current = cg_read_long(memcg, "memory.current"); + + if (current < goal || values_close(current, goal, 3)) + break; + /* Did memory.reclaim return 0 incorrectly? */ + else if (reclaimed) + return false; + + to_reclaim = current - goal; + snprintf(buf, sizeof(buf), "%ld", to_reclaim); + err = cg_write(memcg, "memory.reclaim", buf); + if (!err) + reclaimed = true; + else if (err != -EAGAIN) + return false; + } + return reclaimed; +} + /* * This test checks that memory.reclaim reclaims the given * amount of memory (from both anon and file, if possible). @@ -653,8 +695,7 @@ static int test_memcg_reclaim(const char *root) { int ret = KSFT_FAIL, fd, retries; char *memcg; - long current, expected_usage, to_reclaim; - char buf[64]; + long current, expected_usage; memcg = cg_name(root, "memcg_test"); if (!memcg) @@ -705,41 +746,8 @@ static int test_memcg_reclaim(const char *root) * Reclaim until current reaches 30M, this makes sure we hit both anon * and file if swap is enabled. */ - retries = 5; - while (true) { - int err; - - current = cg_read_long(memcg, "memory.current"); - to_reclaim = current - MB(30); - - /* - * We only keep looping if we get EAGAIN, which means we could - * not reclaim the full amount. - */ - if (to_reclaim <= 0) - goto cleanup; - - - snprintf(buf, sizeof(buf), "%ld", to_reclaim); - err = cg_write(memcg, "memory.reclaim", buf); - if (!err) { - /* - * If writing succeeds, then the written amount should have been - * fully reclaimed (and maybe more). - */ - current = cg_read_long(memcg, "memory.current"); - if (!values_close(current, MB(30), 3) && current > MB(30)) - goto cleanup; - break; - } - - /* The kernel could not reclaim the full amount, try again. */ - if (err == -EAGAIN && retries--) - continue; - - /* We got an unexpected error or ran out of retries. */ + if (!reclaim_until(memcg, MB(30))) goto cleanup; - } ret = KSFT_PASS; cleanup: -- cgit v1.2.3 From 1c74697776e17619e485a40cf8cfdb4bf18fd18e Mon Sep 17 00:00:00 2001 From: Yosry Ahmed Date: Fri, 2 Dec 2022 03:15:12 +0000 Subject: selftests: cgroup: make sure reclaim target memcg is unprotected Make sure that we ignore protection of a memcg that is the target of memcg reclaim. Link: https://lkml.kernel.org/r/20221202031512.1365483-4-yosryahmed@google.com Signed-off-by: Yosry Ahmed Reviewed-by: Roman Gushchin Cc: Chris Down Cc: David Rientjes Cc: Johannes Weiner Cc: Matthew Wilcox Cc: Michal Hocko Cc: Muchun Song Cc: Shakeel Butt Cc: Tejun Heo Cc: Vasily Averin Cc: Vlastimil Babka Cc: Yu Zhao Signed-off-by: Andrew Morton --- tools/testing/selftests/cgroup/test_memcontrol.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'tools') diff --git a/tools/testing/selftests/cgroup/test_memcontrol.c b/tools/testing/selftests/cgroup/test_memcontrol.c index a8f4700353a4..1e616a8c6a9c 100644 --- a/tools/testing/selftests/cgroup/test_memcontrol.c +++ b/tools/testing/selftests/cgroup/test_memcontrol.c @@ -238,6 +238,8 @@ static int cg_test_proc_killed(const char *cgroup) return -1; } +static bool reclaim_until(const char *memcg, long goal); + /* * First, this test creates the following hierarchy: * A memory.min = 0, memory.max = 200M @@ -266,6 +268,12 @@ static int cg_test_proc_killed(const char *cgroup) * unprotected memory in A available, and checks that: * a) memory.min protects pagecache even in this case, * b) memory.low allows reclaiming page cache with low events. + * + * Then we try to reclaim from A/B/C using memory.reclaim until its + * usage reaches 10M. + * This makes sure that: + * (a) We ignore the protection of the reclaim target memcg. + * (b) The previously calculated emin value (~29M) should be dismissed. */ static int test_memcg_protection(const char *root, bool min) { @@ -385,6 +393,9 @@ static int test_memcg_protection(const char *root, bool min) if (!values_close(cg_read_long(parent[1], "memory.current"), MB(50), 3)) goto cleanup; + if (!reclaim_until(children[0], MB(10))) + goto cleanup; + if (min) { ret = KSFT_PASS; goto cleanup; -- cgit v1.2.3 From d88825f22b8f1cad8acb429b6bf0a54c85d7b93f Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Mon, 5 Dec 2022 20:37:14 +0100 Subject: selftests/vm: madv_populate: fix missing MADV_POPULATE_(READ|WRITE) definitions The tests fail to compile in some environments (e.g., Debian 11.5 on x86). Let's simply conditionally define MADV_POPULATE_(READ|WRITE) if not already defined, similar to how the khugepaged.c test handles it. Link: https://lkml.kernel.org/r/20221205193716.276024-3-david@redhat.com Fixes: 39b2e5cae43d ("selftests/vm: make MADV_POPULATE_(READ|WRITE) use in-tree headers") Signed-off-by: David Hildenbrand Cc: Shuah Khan Cc: Yang Li Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/madv_populate.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'tools') diff --git a/tools/testing/selftests/vm/madv_populate.c b/tools/testing/selftests/vm/madv_populate.c index 60547245e479..262eae6b58f2 100644 --- a/tools/testing/selftests/vm/madv_populate.c +++ b/tools/testing/selftests/vm/madv_populate.c @@ -20,6 +20,13 @@ #include "../kselftest.h" #include "vm_util.h" +#ifndef MADV_POPULATE_READ +#define MADV_POPULATE_READ 22 +#endif /* MADV_POPULATE_READ */ +#ifndef MADV_POPULATE_WRITE +#define MADV_POPULATE_WRITE 23 +#endif /* MADV_POPULATE_WRITE */ + /* * For now, we're using 2 MiB of private anonymous memory for all tests. */ -- cgit v1.2.3 From 380969fe5aacdea661d3f9ab32e84327e8624ae2 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Mon, 5 Dec 2022 20:37:15 +0100 Subject: selftests/vm: cow: fix compile warning on 32bit The compiler complains about the conversion of a pointer to an int of different width. Link: https://lkml.kernel.org/r/20221205193716.276024-4-david@redhat.com Fixes: 6f1405efc61b ("selftests/vm: anon_cow: add R/O longterm tests via gup_test") Signed-off-by: David Hildenbrand Cc: Shuah Khan Cc: Yang Li Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/cow.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/vm/cow.c b/tools/testing/selftests/vm/cow.c index 73e05b52c49e..26f6ea3079e2 100644 --- a/tools/testing/selftests/vm/cow.c +++ b/tools/testing/selftests/vm/cow.c @@ -650,7 +650,7 @@ static void do_test_ro_pin(char *mem, size_t size, enum ro_pin_test test, } /* Take a R/O pin. This should trigger unsharing. */ - args.addr = (__u64)mem; + args.addr = (__u64)(uintptr_t)mem; args.size = size; args.flags = fast ? PIN_LONGTERM_TEST_FLAG_USE_FAST : 0; ret = ioctl(gup_fd, PIN_LONGTERM_TEST_START, &args); @@ -669,7 +669,7 @@ static void do_test_ro_pin(char *mem, size_t size, enum ro_pin_test test, * Read back the content via the pin to the temporary buffer and * test if we observed the modification. */ - tmp_val = (__u64)tmp; + tmp_val = (__u64)(uintptr_t)tmp; ret = ioctl(gup_fd, PIN_LONGTERM_TEST_READ, &tmp_val); if (ret) ksft_test_result_fail("PIN_LONGTERM_TEST_READ failed\n"); -- cgit v1.2.3 From 9d789c3b4170574baa4242dd8cae5988cf97d48d Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Mon, 5 Dec 2022 20:37:16 +0100 Subject: selftests/vm: ksm_functional_tests: fixes for 32bit The test currently fails on 32bit. Fixing the "-1ull" vs. "-1ul" seems to make the test pass and the compiler happy. Note: This test is not in mm-stable yet. This fix should be squashed into "selftests/vm: add KSM unmerge tests". Link: https://lkml.kernel.org/r/20221205193716.276024-5-david@redhat.com Signed-off-by: David Hildenbrand Cc: Shuah Khan Cc: Yang Li Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/ksm_functional_tests.c | 4 ++-- tools/testing/selftests/vm/vm_util.c | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/vm/ksm_functional_tests.c b/tools/testing/selftests/vm/ksm_functional_tests.c index 96644be68962..b11b7e5115dc 100644 --- a/tools/testing/selftests/vm/ksm_functional_tests.c +++ b/tools/testing/selftests/vm/ksm_functional_tests.c @@ -42,13 +42,13 @@ static bool range_maps_duplicates(char *addr, unsigned long size) for (offs_a = 0; offs_a < size; offs_a += pagesize) { pfn_a = pagemap_get_pfn(pagemap_fd, addr + offs_a); /* Page not present or PFN not exposed by the kernel. */ - if (pfn_a == -1ull || !pfn_a) + if (pfn_a == -1ul || !pfn_a) continue; for (offs_b = offs_a + pagesize; offs_b < size; offs_b += pagesize) { pfn_b = pagemap_get_pfn(pagemap_fd, addr + offs_b); - if (pfn_b == -1ull || !pfn_b) + if (pfn_b == -1ul || !pfn_b) continue; if (pfn_a == pfn_b) return true; diff --git a/tools/testing/selftests/vm/vm_util.c b/tools/testing/selftests/vm/vm_util.c index 710571902743..40e795624ff3 100644 --- a/tools/testing/selftests/vm/vm_util.c +++ b/tools/testing/selftests/vm/vm_util.c @@ -50,7 +50,7 @@ unsigned long pagemap_get_pfn(int fd, char *start) /* If present (63th bit), PFN is at bit 0 -- 54. */ if (entry & 0x8000000000000000ull) return entry & 0x007fffffffffffffull; - return -1ull; + return -1ul; } void clear_softdirty(void) -- cgit v1.2.3