From 399ab86ea55039f9d0a5f621a68cb4631f796f37 Mon Sep 17 00:00:00 2001 From: Jeff Xu Date: Fri, 14 Jun 2024 23:20:14 +0000 Subject: /proc/pid/smaps: add mseal info for vma MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add sl in /proc/pid/smaps to indicate vma is sealed Link: https://lkml.kernel.org/r/20240614232014.806352-2-jeffxu@google.com Fixes: 8be7258aad44 ("mseal: add mseal syscall") Signed-off-by: Jeff Xu Acked-by: David Hildenbrand Cc: Adhemerval Zanella Cc: Jann Horn Cc: Jorge Lucangeli Obes Cc: Kees Cook Cc: Randy Dunlap Cc: Stephen Röttger Signed-off-by: Andrew Morton --- include/linux/mm.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include/linux') diff --git a/include/linux/mm.h b/include/linux/mm.h index 9a5652c5fadd..eb7c96d24ac0 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -406,6 +406,11 @@ extern unsigned int kobjsize(const void *objp); #define VM_ALLOW_ANY_UNCACHED VM_NONE #endif +#ifdef CONFIG_64BIT +/* VM is sealed, in vm_flags */ +#define VM_SEALED _BITUL(63) +#endif + /* Bits set in the VMA until the stack is in its final location */ #define VM_STACK_INCOMPLETE_SETUP (VM_RAND_READ | VM_SEQ_READ | VM_STACK_EARLY) -- cgit v1.2.3 From ff202303c398ed56386ca4954154de9a96eb732a Mon Sep 17 00:00:00 2001 From: Stephen Brennan Date: Fri, 7 Jun 2024 13:29:53 -0700 Subject: mm: convert page type macros to enum Changing PG_slab from a page flag to a page type in commit 46df8e73a4a3 ("mm: free up PG_slab") in has the unintended consequence of removing the PG_slab constant from kernel debuginfo. The commit does add the value to the vmcoreinfo note, which allows debuggers to find the value without hardcoding it. However it's most flexible to continue representing the constant with an enum. To that end, convert the page type fields into an enum. Debuggers will now be able to detect that PG_slab's type has changed from enum pageflags to enum pagetype. Link: https://lkml.kernel.org/r/20240607202954.1198180-1-stephen.s.brennan@oracle.com Fixes: 46df8e73a4a3 ("mm: free up PG_slab") Signed-off-by: Stephen Brennan Acked-by: Vlastimil Babka Cc: David Hildenbrand Cc: Hao Ge Cc: Matthew Wilcox (Oracle) Cc: Omar Sandoval Cc: Vishal Moola (Oracle) Signed-off-by: Andrew Morton --- include/linux/page-flags.h | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) (limited to 'include/linux') diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 104078afe0b1..b9e914e1face 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -944,15 +944,18 @@ PAGEFLAG_FALSE(HasHWPoisoned, has_hwpoisoned) * mistaken for a page type value. */ -#define PAGE_TYPE_BASE 0xf0000000 -/* Reserve 0x0000007f to catch underflows of _mapcount */ -#define PAGE_MAPCOUNT_RESERVE -128 -#define PG_buddy 0x00000080 -#define PG_offline 0x00000100 -#define PG_table 0x00000200 -#define PG_guard 0x00000400 -#define PG_hugetlb 0x00000800 -#define PG_slab 0x00001000 +enum pagetype { + PG_buddy = 0x00000080, + PG_offline = 0x00000100, + PG_table = 0x00000200, + PG_guard = 0x00000400, + PG_hugetlb = 0x00000800, + PG_slab = 0x00001000, + + PAGE_TYPE_BASE = 0xf0000000, + /* Reserve 0x0000007f to catch underflows of _mapcount */ + PAGE_MAPCOUNT_RESERVE = -128, +}; #define PageType(page, flag) \ ((page->page_type & (PAGE_TYPE_BASE | flag)) == PAGE_TYPE_BASE) -- cgit v1.2.3 From bf14ed81f571f8dba31cd72ab2e50fbcc877cc31 Mon Sep 17 00:00:00 2001 From: yangge Date: Thu, 20 Jun 2024 08:59:50 +0800 Subject: mm/page_alloc: Separate THP PCP into movable and non-movable categories Since commit 5d0a661d808f ("mm/page_alloc: use only one PCP list for THP-sized allocations") no longer differentiates the migration type of pages in THP-sized PCP list, it's possible that non-movable allocation requests may get a CMA page from the list, in some cases, it's not acceptable. If a large number of CMA memory are configured in system (for example, the CMA memory accounts for 50% of the system memory), starting a virtual machine with device passthrough will get stuck. During starting the virtual machine, it will call pin_user_pages_remote(..., FOLL_LONGTERM, ...) to pin memory. Normally if a page is present and in CMA area, pin_user_pages_remote() will migrate the page from CMA area to non-CMA area because of FOLL_LONGTERM flag. But if non-movable allocation requests return CMA memory, migrate_longterm_unpinnable_pages() will migrate a CMA page to another CMA page, which will fail to pass the check in check_and_migrate_movable_pages() and cause migration endless. Call trace: pin_user_pages_remote --__gup_longterm_locked // endless loops in this function ----_get_user_pages_locked ----check_and_migrate_movable_pages ------migrate_longterm_unpinnable_pages --------alloc_migration_target This problem will also have a negative impact on CMA itself. For example, when CMA is borrowed by THP, and we need to reclaim it through cma_alloc() or dma_alloc_coherent(), we must move those pages out to ensure CMA's users can retrieve that contigous memory. Currently, CMA's memory is occupied by non-movable pages, meaning we can't relocate them. As a result, cma_alloc() is more likely to fail. To fix the problem above, we add one PCP list for THP, which will not introduce a new cacheline for struct per_cpu_pages. THP will have 2 PCP lists, one PCP list is used by MOVABLE allocation, and the other PCP list is used by UNMOVABLE allocation. MOVABLE allocation contains GPF_MOVABLE, and UNMOVABLE allocation contains GFP_UNMOVABLE and GFP_RECLAIMABLE. Link: https://lkml.kernel.org/r/1718845190-4456-1-git-send-email-yangge1116@126.com Fixes: 5d0a661d808f ("mm/page_alloc: use only one PCP list for THP-sized allocations") Signed-off-by: yangge Cc: Baolin Wang Cc: Barry Song <21cnbao@gmail.com> Cc: Mel Gorman Cc: Signed-off-by: Andrew Morton --- include/linux/mmzone.h | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'include/linux') diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 8f9c9590a42c..586a8f0104d7 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -654,13 +654,12 @@ enum zone_watermarks { }; /* - * One per migratetype for each PAGE_ALLOC_COSTLY_ORDER. One additional list - * for THP which will usually be GFP_MOVABLE. Even if it is another type, - * it should not contribute to serious fragmentation causing THP allocation - * failures. + * One per migratetype for each PAGE_ALLOC_COSTLY_ORDER. Two additional lists + * are added for THP. One PCP list is used by GPF_MOVABLE, and the other PCP list + * is used by GFP_UNMOVABLE and GFP_RECLAIMABLE. */ #ifdef CONFIG_TRANSPARENT_HUGEPAGE -#define NR_PCP_THP 1 +#define NR_PCP_THP 2 #else #define NR_PCP_THP 0 #endif -- cgit v1.2.3