linux.git/arch/alpha/include, branch v7.1-rc5

ring-buffer: Flush and stop persistent ring buffer on panic

2026-05-21T12:20:58+00:00

On real hardware, panic and machine reboot may not flush hardware cache
to memory. This means the persistent ring buffer, which relies on a
coherent state of memory, may not have its events written to the buffer
and they may be lost. Moreover, there may be inconsistency with the
counters which are used for validation of the integrity of the
persistent ring buffer which may cause all data to be discarded.

To avoid this issue, stop recording of the ring buffer on panic and
flush the cache of the ring buffer's memory.

Fixes: e645535a954a ("tracing: Add option to use memmapped memory for trace boot instance")
Cc: stable@vger.kernel.org
Cc: Will Deacon 
Cc: Mathieu Desnoyers 
Cc: Ian Rogers 
Link: https://patch.msgid.link/177751969602.2136606.12031934362587643488.stgit@mhiramat.tok.corp.google.com
Signed-off-by: Masami Hiramatsu (Google) 
Acked-by: Catalin Marinas 
Acked-by: Geert Uytterhoeven 
Signed-off-by: Steven Rostedt

Merge tag 'alpha-for-v7.1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/lindholm/alpha

2026-04-17T15:34:43+00:00

Pull alpha updates from Magnus Lindholm:
 "One fix to silence pgprot_modify() compiler warnings, and one patch
  adding SECCOMP/SECCOMP_FILTER support together with the syscall and
  ptrace fixes needed for it"

* tag 'alpha-for-v7.1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/lindholm/alpha:
  alpha: Define pgprot_modify to silence tautological comparison warnings
  alpha: add support for SECCOMP and SECCOMP_FILTER

Merge tag 'mm-nonmm-stable-2026-04-15-04-20' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2026-04-17T03:11:56+00:00

Pull non-MM updates from Andrew Morton:

 - "pid: make sub-init creation retryable" (Oleg Nesterov)

   Make creation of init in a new namespace more robust by clearing away
   some historical cruft which is no longer needed. Also some
   documentation fixups

 - "selftests/fchmodat2: Error handling and general" (Mark Brown)

   Fix and a cleanup for the fchmodat2() syscall selftest

 - "lib: polynomial: Move to math/ and clean up" (Andy Shevchenko)

 - "hung_task: Provide runtime reset interface for hung task detector"
   (Aaron Tomlin)

   Give administrators the ability to zero out
   /proc/sys/kernel/hung_task_detect_count

 - "tools/getdelays: use the static UAPI headers from
   tools/include/uapi" (Thomas Weißschuh)

   Teach getdelays to use the in-kernel UAPI headers rather than the
   system-provided ones

 - "watchdog/hardlockup: Improvements to hardlockup" (Mayank Rungta)

   Several cleanups and fixups to the hardlockup detector code and its
   documentation

 - "lib/bch: fix undefined behavior from signed left-shifts" (Josh Law)

   A couple of small/theoretical fixes in the bch code

 - "ocfs2/dlm: fix two bugs in dlm_match_regions()" (Junrui Luo)

 - "cleanup the RAID5 XOR library" (Christoph Hellwig)

   A quite far-reaching cleanup to this code. I can't do better than to
   quote Christoph:

     "The XOR library used for the RAID5 parity is a bit of a mess right
      now. The main file sits in crypto/ despite not being cryptography
      and not using the crypto API, with the generic implementations
      sitting in include/asm-generic and the arch implementations
      sitting in an asm/ header in theory. The latter doesn't work for
      many cases, so architectures often build the code directly into
      the core kernel, or create another module for the architecture
      code.

      Change this to a single module in lib/ that also contains the
      architecture optimizations, similar to the library work Eric
      Biggers has done for the CRC and crypto libraries later. After
      that it changes to better calling conventions that allow for
      smarter architecture implementations (although none is contained
      here yet), and uses static_call to avoid indirection function call
      overhead"

 - "lib/list_sort: Clean up list_sort() scheduling workarounds"
   (Kuan-Wei Chiu)

   Clean up this library code by removing a hacky thing which was added
   for UBIFS, which UBIFS doesn't actually need

 - "Fix bugs in extract_iter_to_sg()" (Christian Ehrhardt)

   Fix a few bugs in the scatterlist code, add in-kernel tests for the
   now-fixed bugs and fix a leak in the test itself

 - "kdump: Enable LUKS-encrypted dump target support in ARM64 and
   PowerPC" (Coiby Xu)

   Enable support of the LUKS-encrypted device dump target on arm64 and
   powerpc

 - "ocfs2: consolidate extent list validation into block read callbacks"
   (Joseph Qi)

   Cleanup, simplify, and make more robust ocfs2's validation of extent
   list fields (Kernel test robot loves mounting corrupted fs images!)

* tag 'mm-nonmm-stable-2026-04-15-04-20' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (127 commits)
  ocfs2: validate group add input before caching
  ocfs2: validate bg_bits during freefrag scan
  ocfs2: fix listxattr handling when the buffer is full
  doc: watchdog: fix typos etc
  update Sean's email address
  ocfs2: use get_random_u32() where appropriate
  ocfs2: split transactions in dio completion to avoid credit exhaustion
  ocfs2: remove redundant l_next_free_rec check in __ocfs2_find_path()
  ocfs2: validate extent block list fields during block read
  ocfs2: remove empty extent list check in ocfs2_dx_dir_lookup_rec()
  ocfs2: validate dx_root extent list fields during block read
  ocfs2: fix use-after-free in ocfs2_fault() when VM_FAULT_RETRY
  ocfs2: handle invalid dinode in ocfs2_group_extend
  .get_maintainer.ignore: add Askar
  ocfs2: validate bg_list extent bounds in discontig groups
  checkpatch: exclude forward declarations of const structs
  tools/accounting: handle truncated taskstats netlink messages
  taskstats: set version in TGID exit notifications
  ocfs2/heartbeat: fix slot mapping rollback leaks on error paths
  arm64,ppc64le/kdump: pass dm-crypt keys to kdump kernel
  ...

alpha: Define pgprot_modify to silence tautological comparison warnings

2026-04-12T17:14:37+00:00

Alpha's pgprot_noncached, pgprot_writecombine, and pgprot_device are
all identity macros, so the generic pgprot_modify() produces
tautological self-comparisons that GCC warns about:

  include/linux/pgtable.h:1701:25: warning: self-comparison always
  evaluates to true [-Wtautological-compare]

Since all caching attributes are no-ops on Alpha, define
pgprot_modify() to simply return newprot.

Assisted-by: Claude:claude-opus-4-6
Signed-off-by: Matt Turner 
Reviewed-by: Magnus Lindholm 
Link: https://lore.kernel.org/r/20260403150128.488513-1-mattst88@gmail.com
Signed-off-by: Magnus Lindholm

alpha: add support for SECCOMP and SECCOMP_FILTER

2026-04-12T17:13:59+00:00

Add SECCOMP and SECCOMP_FILTER support to the Alpha architecture and fix
syscall entry and ptrace issues uncovered by the seccomp-bpf selftests.

The syscall entry path is reworked to consistently track syscall state
using r0, r1 and r2:
  - r1 holds the active syscall number
  - r2 preserves the original syscall number for restart
  - r0 carries the return value, with r19 (a3) indicating success/error

This allows syscall restarts to be permitted only for valid ERESTART*
return codes and prevents kernel-internal restart values from leaking to
userspace. The syscall tracing error marker is corrected to use the saved
syscall number slot, matching the Alpha ABI.

Additionally, implement minimal PTRACE_GETREGSET and PTRACE_SETREGSET
support for NT_PRSTATUS, exporting struct pt_regs directly. This fixes
ptrace-based seccomp tests that previously failed with -EIO.

With these changes, seccomp-bpf and ptrace syscall tests pass reliably on
Alpha.

Tested-by: Michael Cree 
Signed-off-by: Magnus Lindholm 
Link: https://lore.kernel.org/r/20260409171439.8759-2-linmag7@gmail.com
Signed-off-by: Magnus Lindholm

arch, mm: consolidate empty_zero_page

2026-04-05T20:53:01+00:00

Reduce 22 declarations of empty_zero_page to 3 and 23 declarations of
ZERO_PAGE() to 4.

Every architecture defines empty_zero_page that way or another, but for the
most of them it is always a page aligned page in BSS and most definitions
of ZERO_PAGE do virt_to_page(empty_zero_page).

Move Linus vetted x86 definition of empty_zero_page and ZERO_PAGE() to the
core MM and drop these definitions in architectures that do not implement
colored zero page (MIPS and s390).

ZERO_PAGE() remains a macro because turning it to a wrapper for a static
inline causes severe pain in header dependencies.

For the most part the change is mechanical, with these being noteworthy:

* alpha: aliased empty_zero_page with ZERO_PGE that was also used for boot
  parameters. Switching to a generic empty_zero_page removes the aliasing
  and keeps ZERO_PGE for boot parameters only
* arm64: uses __pa_symbol() in ZERO_PAGE() so that definition of
  ZERO_PAGE() is kept intact.
* m68k/parisc/um: allocated empty_zero_page from memblock,
  although they do not support zero page coloring and having it in BSS
  will work fine.
* sparc64 can have empty_zero_page in BSS rather allocate it, but it
  can't use virt_to_page() for BSS. Keep it's definition of ZERO_PAGE()
  but instead of allocating it, make mem_map_zero point to
  empty_zero_page.
* sh: used empty_zero_page for boot parameters at the very early boot.
  Rename the parameters page to boot_params_page and let sh use the generic
  empty_zero_page.
* hexagon: had an amusing comment about empty_zero_page

	/* A handy thing to have if one has the RAM. Declared in head.S */

  that unfortunately had to go :)

Link: https://lkml.kernel.org/r/20260211103141.3215197-4-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) 
Acked-by: Helge Deller 		[parisc]
Tested-by: Helge Deller 		[parisc]
Reviewed-by: Christophe Leroy (CS GROUP) 
Acked-by: Dave Hansen 
Acked-by: Catalin Marinas 
Acked-by: Magnus Lindholm 	[alpha]
Acked-by: Dinh Nguyen 	[nios2]
Acked-by: Andreas Larsson 	[sparc]
Acked-by: David Hildenbrand (Arm) 
Acked-by: Liam R. Howlett 
Cc: "Borislav Petkov (AMD)" 
Cc: David S. Miller 
Cc: Geert Uytterhoeven 
Cc: Guo Ren 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: Johannes Berg 
Cc: John Paul Adrian Glaubitz 
Cc: Lorenzo Stoakes 
Cc: Madhavan Srinivasan 
Cc: Matt Turner 
Cc: Max Filippov 
Cc: Michael Ellerman 
Cc: Michal Hocko 
Cc: Michal Simek 
Cc: Palmer Dabbelt 
Cc: Richard Weinberger 
Cc: Russell King 
Cc: Stafford Horne 
Cc: Suren Baghdasaryan 
Cc: Vineet Gupta 
Cc: Vlastimil Babka 
Cc: Will Deacon 
Signed-off-by: Andrew Morton

xor: make xor.ko self-contained in lib/raid/

2026-04-03T06:36:20+00:00

Move the asm/xor.h headers to lib/raid/xor/$(SRCARCH)/xor_arch.h and
include/linux/raid/xor_impl.h to lib/raid/xor/xor_impl.h so that the
xor.ko module implementation is self-contained in lib/raid/.

As this remove the asm-generic mechanism a new kconfig symbol is added to
indicate that a architecture-specific implementations exists, and
xor_arch.h should be included.

Link: https://lkml.kernel.org/r/20260327061704.3707577-22-hch@lst.de
Signed-off-by: Christoph Hellwig 
Reviewed-by: Eric Biggers 
Tested-by: Eric Biggers 
Cc: Albert Ou 
Cc: Alexander Gordeev 
Cc: Alexandre Ghiti 
Cc: Andreas Larsson 
Cc: Anton Ivanov 
Cc: Ard Biesheuvel 
Cc: Arnd Bergmann 
Cc: "Borislav Petkov (AMD)" 
Cc: Catalin Marinas 
Cc: Chris Mason 
Cc: Christian Borntraeger 
Cc: Dan Williams 
Cc: David S. Miller 
Cc: David Sterba 
Cc: Heiko Carstens 
Cc: Herbert Xu 
Cc: "H. Peter Anvin" 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: Jason A. Donenfeld 
Cc: Johannes Berg 
Cc: Li Nan 
Cc: Madhavan Srinivasan 
Cc: Magnus Lindholm 
Cc: Matt Turner 
Cc: Michael Ellerman 
Cc: Nicholas Piggin 
Cc: Palmer Dabbelt 
Cc: Richard Henderson 
Cc: Richard Weinberger 
Cc: Russell King 
Cc: Song Liu 
Cc: Sven Schnelle 
Cc: Ted Ts'o 
Cc: Vasily Gorbik 
Cc: WANG Xuerui 
Cc: Will Deacon 
Signed-off-by: Andrew Morton

alpha: move the XOR code to lib/raid/

2026-04-03T06:36:17+00:00

Move the optimized XOR code out of line into lib/raid.

Note that the giant inline assembly block might be better off as a
separate assembly source file now, but I'll leave that to the alpha
maintainers.

Link: https://lkml.kernel.org/r/20260327061704.3707577-12-hch@lst.de
Signed-off-by: Christoph Hellwig 
Acked-by: Magnus Lindholm 
Tested-by: Magnus Lindholm 
Reviewed-by: Eric Biggers 
Tested-by: Eric Biggers 
Cc: Albert Ou 
Cc: Alexander Gordeev 
Cc: Alexandre Ghiti 
Cc: Andreas Larsson 
Cc: Anton Ivanov 
Cc: Ard Biesheuvel 
Cc: Arnd Bergmann 
Cc: "Borislav Petkov (AMD)" 
Cc: Catalin Marinas 
Cc: Chris Mason 
Cc: Christian Borntraeger 
Cc: Dan Williams 
Cc: David S. Miller 
Cc: David Sterba 
Cc: Heiko Carstens 
Cc: Herbert Xu 
Cc: "H. Peter Anvin" 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: Jason A. Donenfeld 
Cc: Johannes Berg 
Cc: Li Nan 
Cc: Madhavan Srinivasan 
Cc: Matt Turner 
Cc: Michael Ellerman 
Cc: Nicholas Piggin 
Cc: Palmer Dabbelt 
Cc: Richard Henderson 
Cc: Richard Weinberger 
Cc: Russell King 
Cc: Song Liu 
Cc: Sven Schnelle 
Cc: Ted Ts'o 
Cc: Vasily Gorbik 
Cc: WANG Xuerui 
Cc: Will Deacon 
Signed-off-by: Andrew Morton

xor: remove macro abuse for XOR implementation registrations

2026-04-03T06:36:17+00:00

Drop the pretty confusing historic XOR_TRY_TEMPLATES and
XOR_SELECT_TEMPLATE, and instead let the architectures provide a
arch_xor_init that calls either xor_register to register candidates or
xor_force to force a specific implementation.

Link: https://lkml.kernel.org/r/20260327061704.3707577-10-hch@lst.de
Signed-off-by: Christoph Hellwig 
Reviewed-by: Eric Biggers 
Tested-by: Eric Biggers 
Cc: Albert Ou 
Cc: Alexander Gordeev 
Cc: Alexandre Ghiti 
Cc: Andreas Larsson 
Cc: Anton Ivanov 
Cc: Ard Biesheuvel 
Cc: Arnd Bergmann 
Cc: "Borislav Petkov (AMD)" 
Cc: Catalin Marinas 
Cc: Chris Mason 
Cc: Christian Borntraeger 
Cc: Dan Williams 
Cc: David S. Miller 
Cc: David Sterba 
Cc: Heiko Carstens 
Cc: Herbert Xu 
Cc: "H. Peter Anvin" 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: Jason A. Donenfeld 
Cc: Johannes Berg 
Cc: Li Nan 
Cc: Madhavan Srinivasan 
Cc: Magnus Lindholm 
Cc: Matt Turner 
Cc: Michael Ellerman 
Cc: Nicholas Piggin 
Cc: Palmer Dabbelt 
Cc: Richard Henderson 
Cc: Richard Weinberger 
Cc: Russell King 
Cc: Song Liu 
Cc: Sven Schnelle 
Cc: Ted Ts'o 
Cc: Vasily Gorbik 
Cc: WANG Xuerui 
Cc: Will Deacon 
Signed-off-by: Andrew Morton

alpha: add missing address argument in call to page_table_check_pte_clear()

2026-02-13T18:44:31+00:00

After the merge of the alpha and mm trees, this code does not compile,
as a parameter is missing in a call to page_table_check_pte_clear().

The parameter was re-added in commit d7b4b67eb6b3 ("mm/page_table_check:
reinstate address parameter in [__]page_table_check_pte_clear()").
The alpha-specific code was newly added in commit dd5712f3379c ("alpha:
fix user-space corruption during memory compaction").

Fixes: 4cff5c05e076 ("Merge tag 'mm-stable-2026-02-11-19-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm")
Signed-off-by: Thomas Weißschuh 
Acked-by: Magnus Lindholm 
Signed-off-by: Linus Torvalds