Pull s390 updates from Heiko Carstens: - Drop support for outdated 3590/3592 and 3480 tape devices, and limit support to virtualized 3490E types devices - Implement exception based WARN() and WARN_ONCE() similar to x86 - Slightly optimize preempt primitives like __preempt_count_add() and __preempt_count_dec_and_test() - A couple of small fixes and improvements * tag 's390-7.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (35 commits) s390/tape: Consolidate tape config options and modules s390/cio: Fix device lifecycle handling in css_alloc_subchannel() s390/tape: Rename tape_34xx.c to tape_3490.c s390/tape: Cleanup sense data analysis and error handling s390/tape: Remove 3480 tape device type s390/tape: Remove unused command definitions s390/tape: Remove special block id handling s390/tape: Remove tape load display support s390/tape: Remove support for 3590/3592 models s390/kexec: Emit an error message when cmdline is too long s390/configs: Enable BLK_DEV_NULL_BLK as module s390: Document s390 stackprotector support s390/perf: Disable register readout on sampling events s390/Kconfig: Define non-zero ILLEGAL_POINTER_VALUE s390/bug: Prevent tail-call optimization s390/bug: Skip __WARN_trap() in call traces s390/bug: Implement WARN_ONCE() s390/bug: Implement __WARN_printf() s390/traps: Copy monitor code to pt_regs s390/bug: Introduce and use monitor code macro ...
Define CONFIG_ILLEGAL_POINTER_VALUE to the eye-catching non-zero value
of 0xdead000000000000, consistent with other architectures. Assert at
compile-time that the poison pointers that include/linux/poison.h
defines based on this illegal pointer are beyond the largest useful
virtual addresses. Also, assert at compile-time that the range of poison
pointers per include/linux/poison.h (currently a range of less than
0x10000 addresses) does not overlap with the range used for address
handles for s390's non-MIO PCI instructions.
This enables s390 to track the DMA mappings by the network stack's
page_pool that was introduced with [0]. Other functional changes are not
intended.
Other archictectures have introduced this for various other reasons with
commit 5c178472af24 ("riscv: define ILLEGAL_POINTER_VALUE for 64bit")
commit f6853eb561fb ("powerpc/64: Define ILLEGAL_POINTER_VALUE for 64-bit")
commit bf0c4e047324 ("arm64: kconfig: Move LIST_POISON to a safe value")
commit a29815a333c6 ("core, x86: make LIST_POISON less deadly")
[0] https://lore.kernel.org/all/20250409-page-pool-track-dma-v9-0-6a9ef2e0cba8@redhat.com/
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Gerd Bayer <gbayer@linux.ibm.com>
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Since commit 3e86e4d74c04 ("kbuild: keep .modinfo section in
vmlinux.unstripped") the .modinfo section which has SHF_ALLOC ends up
in bzImage after the SecureBoot trailer. This breaks SecureBoot because
the bootloader can no longer find the SecureBoot trailer with kernel's
signature at the expected location in bzImage. To fix the bug,
move discarded sections before the ELF_DETAILS macro and discard
the .modinfo section which is not needed by the decompressor.
Fixes: 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped")
Cc: stable@vger.kernel.org
Suggested-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Tested-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Add -Wno-default-const-init-unsafe to boot KBUILD_CFLAGS, similar to
scripts/Makefile.extrawarn, since clang generates warnings for the dummy
variable in typecheck():
CC arch/s390/boot/version.o
arch/s390/include/asm/ptrace.h:221:9: warning: default initialization of an object of type 'typeof (regs->psw)' (aka 'const psw_t') leaves the object uninitialized [-Wdefault-const-init-var-unsafe]
221 | return psw_bits(regs->psw).pstate;
| ^
arch/s390/include/asm/ptrace.h:98:2: note: expanded from macro 'psw_bits'
98 | typecheck(psw_t, __psw); \
| ^
include/linux/typecheck.h:11:12: note: expanded from macro 'typecheck'
11 | typeof(x) __dummy2; \
| ^
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Make boot_pte_alloc() always allocate a full PAGE_SIZE page for
PTE tables, instead of carving two 2K PTE tables out of a single
4K page, similar to commit daa8af80d283 ("s390/mm: Allocate page
table with PAGE_SIZE granularity").
This mirrors the change in the vmem code and ensures that boot page
tables backing the early KASAN shadow can later be fully freed by
the vmem page-table teardown helpers (e.g. when unmapping early
KASAN shadow on memory hotplug).
The leftover-based allocation was originally added to reduce physmem
allocator fragmentation when EDAT was disabled. On current hardware
EDAT1 is available on all production systems, so the complexity is no
longer justified and gets in the way of freeing the shadow mappings.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Pull MM updates from Andrew Morton:
"__vmalloc()/kvmalloc() and no-block support" (Uladzislau Rezki)
Rework the vmalloc() code to support non-blocking allocations
(GFP_ATOIC, GFP_NOWAIT)
"ksm: fix exec/fork inheritance" (xu xin)
Fix a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not
inherited across fork/exec
"mm/zswap: misc cleanup of code and documentations" (SeongJae Park)
Some light maintenance work on the zswap code
"mm/page_owner: add debugfs files 'show_handles' and 'show_stacks_handles'" (Mauricio Faria de Oliveira)
Enhance the /sys/kernel/debug/page_owner debug feature by adding
unique identifiers to differentiate the various stack traces so
that userspace monitoring tools can better match stack traces over
time
"mm/page_alloc: pcp->batch cleanups" (Joshua Hahn)
Minor alterations to the page allocator's per-cpu-pages feature
"Improve UFFDIO_MOVE scalability by removing anon_vma lock" (Lokesh Gidra)
Address a scalability issue in userfaultfd's UFFDIO_MOVE operation
"kasan: cleanups for kasan_enabled() checks" (Sabyrzhan Tasbolatov)
"drivers/base/node: fold node register and unregister functions" (Donet Tom)
Clean up the NUMA node handling code a little
"mm: some optimizations for prot numa" (Kefeng Wang)
Cleanups and small optimizations to the NUMA allocation hinting
code
"mm/page_alloc: Batch callers of free_pcppages_bulk" (Joshua Hahn)
Address long lock hold times at boot on large machines. These were
causing (harmless) softlockup warnings
"optimize the logic for handling dirty file folios during reclaim" (Baolin Wang)
Remove some now-unnecessary work from page reclaim
"mm/damon: allow DAMOS auto-tuned for per-memcg per-node memory usage" (SeongJae Park)
Enhance the DAMOS auto-tuning feature
"mm/damon: fixes for address alignment issues in DAMON_LRU_SORT and DAMON_RECLAIM" (Quanmin Yan)
Fix DAMON_LRU_SORT and DAMON_RECLAIM with certain userspace
configuration
"expand mmap_prepare functionality, port more users" (Lorenzo Stoakes)
Enhance the new(ish) file_operations.mmap_prepare() method and port
additional callsites from the old ->mmap() over to ->mmap_prepare()
"Fix stale IOTLB entries for kernel address space" (Lu Baolu)
Fix a bug (and possible security issue on non-x86) in the IOMMU
code. In some situations the IOMMU could be left hanging onto a
stale kernel pagetable entry
"mm/huge_memory: cleanup __split_unmapped_folio()" (Wei Yang)
Clean up and optimize the folio splitting code
"mm, swap: misc cleanup and bugfix" (Kairui Song)
Some cleanups and a minor fix in the swap discard code
"mm/damon: misc documentation fixups" (SeongJae Park)
"mm/damon: support pin-point targets removal" (SeongJae Park)
Permit userspace to remove a specific monitoring target in the
middle of the current targets list
"mm: MISC follow-up patches for linux/pgalloc.h" (Harry Yoo)
A couple of cleanups related to mm header file inclusion
"mm/swapfile.c: select swap devices of default priority round robin" (Baoquan He)
improve the selection of swap devices for NUMA machines
"mm: Convert memory block states (MEM_*) macros to enums" (Israel Batista)
Change the memory block labels from macros to enums so they will
appear in kernel debug info
"ksm: perform a range-walk to jump over holes in break_ksm" (Pedro Demarchi Gomes)
Address an inefficiency when KSM unmerges an address range
"mm/damon/tests: fix memory bugs in kunit tests" (SeongJae Park)
Fix leaks and unhandled malloc() failures in DAMON userspace unit
tests
"some cleanups for pageout()" (Baolin Wang)
Clean up a couple of minor things in the page scanner's
writeback-for-eviction code
"mm/hugetlb: refactor sysfs/sysctl interfaces" (Hui Zhu)
Move hugetlb's sysfs/sysctl handling code into a new file
"introduce VM_MAYBE_GUARD and make it sticky" (Lorenzo Stoakes)
Make the VMA guard regions available in /proc/pid/smaps and
improves the mergeability of guarded VMAs
"mm: perform guard region install/remove under VMA lock" (Lorenzo Stoakes)
Reduce mmap lock contention for callers performing VMA guard region
operations
"vma_start_write_killable" (Matthew Wilcox)
Start work on permitting applications to be killed when they are
waiting on a read_lock on the VMA lock
"mm/damon/tests: add more tests for online parameters commit" (SeongJae Park)
Add additional userspace testing of DAMON's "commit" feature
"mm/damon: misc cleanups" (SeongJae Park)
"make VM_SOFTDIRTY a sticky VMA flag" (Lorenzo Stoakes)
Address the possible loss of a VMA's VM_SOFTDIRTY flag when that
VMA is merged with another
"mm: support device-private THP" (Balbir Singh)
Introduce support for Transparent Huge Page (THP) migration in zone
device-private memory
"Optimize folio split in memory failure" (Zi Yan)
"mm/huge_memory: Define split_type and consolidate split support checks" (Wei Yang)
Some more cleanups in the folio splitting code
"mm: remove is_swap_[pte, pmd]() + non-swap entries, introduce leaf entries" (Lorenzo Stoakes)
Clean up our handling of pagetable leaf entries by introducing the
concept of 'software leaf entries', of type softleaf_t
"reparent the THP split queue" (Muchun Song)
Reparent the THP split queue to its parent memcg. This is in
preparation for addressing the long-standing "dying memcg" problem,
wherein dead memcg's linger for too long, consuming memory
resources
"unify PMD scan results and remove redundant cleanup" (Wei Yang)
A little cleanup in the hugepage collapse code
"zram: introduce writeback bio batching" (Sergey Senozhatsky)
Improve zram writeback efficiency by introducing batched bio
writeback support
"memcg: cleanup the memcg stats interfaces" (Shakeel Butt)
Clean up our handling of the interrupt safety of some memcg stats
"make vmalloc gfp flags usage more apparent" (Vishal Moola)
Clean up vmalloc's handling of incoming GFP flags
"mm: Add soft-dirty and uffd-wp support for RISC-V" (Chunyan Zhang)
Teach soft dirty and userfaultfd write protect tracking to use
RISC-V's Svrsw60t59b extension
"mm: swap: small fixes and comment cleanups" (Youngjun Park)
Fix a small bug and clean up some of the swap code
"initial work on making VMA flags a bitmap" (Lorenzo Stoakes)
Start work on converting the vma struct's flags to a bitmap, so we
stop running out of them, especially on 32-bit
"mm/swapfile: fix and cleanup swap list iterations" (Youngjun Park)
Address a possible bug in the swap discard code and clean things
up a little
[ This merge also reverts commit ebb9aeb980e5 ("vfio/nvgrace-gpu:
register device memory for poison handling") because it looks
broken to me, I've asked for clarification - Linus ]
* tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits)
mm: fix vma_start_write_killable() signal handling
mm/swapfile: use plist_for_each_entry in __folio_throttle_swaprate
mm/swapfile: fix list iteration when next node is removed during discard
fs/proc/task_mmu.c: fix make_uffd_wp_huge_pte() huge pte handling
mm/kfence: add reboot notifier to disable KFENCE on shutdown
memcg: remove inc/dec_lruvec_kmem_state helpers
selftests/mm/uffd: initialize char variable to Null
mm: fix DEBUG_RODATA_TEST indentation in Kconfig
mm: introduce VMA flags bitmap type
tools/testing/vma: eliminate dependency on vma->__vm_flags
mm: simplify and rename mm flags function for clarity
mm: declare VMA flags by bit
zram: fix a spelling mistake
mm/page_alloc: optimize lowmem_reserve max lookup using its semantic monotonicity
mm/vmscan: skip increasing kswapd_failures when reclaim was boosted
pagemap: update BUDDY flag documentation
mm: swap: remove scan_swap_map_slots() references from comments
mm: swap: change swap_alloc_slow() to void
mm, swap: remove redundant comment for read_swap_cache_async
mm, swap: use SWP_SOLIDSTATE to determine if swap is rotational
...
Stackprotector support was previously unavailable on s390 because by
default compilers generate code which is not suitable for the kernel:
the canary value is accessed via thread local storage, where the address
of thread local storage is within access registers 0 and 1.
Using those registers also for the kernel would come with a significant
performance impact and more complicated kernel entry/exit code, since
access registers contents would have to be exchanged on every kernel entry
and exit.
With the upcoming gcc 16 release new compiler options will become available
which allow to generate code suitable for the kernel. [1]
Compiler option -mstack-protector-guard=global instructs gcc to generate
stackprotector code that refers to a global stackprotector canary value via
symbol __stack_chk_guard. Access to this value is guaranteed to occur via
larl and lgrl instructions.
Furthermore, compiler option -mstack-protector-guard-record generates a
section containing all code addresses that reference the canary value.
To allow for per task canary values the instructions which load the address
of __stack_chk_guard are patched so they access a lowcore field instead: a
per task canary value is available within the task_struct of each task, and
is written to the per-cpu lowcore location on each context switch.
Also add sanity checks and debugging option to be consistent with other
kernel code patching mechanisms.
Full debugging output can be enabled with the following kernel command line
options:
debug_stackprotector
bootdebug
ignore_loglevel
earlyprintk
dyndbg="file stackprotector.c +p"
Example debug output:
stackprot: 0000021e402d4eda: c010005a9ae3 -> c01f00070240
where "<insn address>: <old insn> -> <new insn>".
[1] gcc commit 0cd1f03939d5 ("s390: Support global stack protector")
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
There shouldn't be any 31 bit code around anymore that matters. Remove the compat layer support required to run 31 bit code. Reason for removal is code simplification and reduced test effort. Note that this comes without any deprecation warnings added to config options, or kernel messages, since most likely those would be ignored anyway. If it turns out there is still a reason to keep the compat layer this can be reverted at any time in the future. Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Use a standard "_t" suffix for psw_t32 and rename it to psw32_t. Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
INVALID_PHYS_ADDR has very similar definitions across the code base. Hence just move that inside header <liux/mm.h> for more generic usage. Also drop the now redundant ones which are no longer required. Link: https://lkml.kernel.org/r/20251021025638.2420216-1-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> [s390] Signed-off-by: Andrew Morton <akpm@linux-foundation.org>