When the unused exports whitelist is provided, the symbol protection bit
is set for symbols not present in the unused exports whitelist.
The flag will be used in the following commit to prevent unsigned
modules from the using symbols other than those explicitly declared by
the such modules ahead of time.
Bug: 519119852
Change-Id: Ibddd628a8b1463397cc95d3d8f556b9bc82bf623
Signed-off-by: Siddharth Nayyar <sidnayyar@google.com>
Pull Kbuild fixes from Nicolas Schier:
- modpost: prevent stack buffer overflow in do_input_entry() and
do_dmi_entry()
Defensively replace unbound sprintf() calls in file2alias to prevent
silent stack overflows and detect alias name overflows with proper
error message.
- kbuild: pacman-pkg: make "rc" releases adhere to pacman versioning
scheme
Enable smooth upgrades from "rc" releases w/ pacman packages.
* tag 'kbuild-fixes-7.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux:
kbuild: pacman-pkg: make "rc" releases adhere to pacman versioning scheme
modpost: prevent stack buffer overflow in do_input_entry() and do_dmi_entry()
Pull misc fixes from Andrew Morton:
"14 hotfixes. 9 are for MM. 10 are cc:stable and the remainder are for
post-7.1 issues or aren't deemed suitable for backporting.
There's a two-patch MAINTAINERS series from Mike Rapoport which
updates us for the new KEXEC/KDUMP/crash/LUO/etc arrangements. And
another two-patch series from Muchun Song to fix a couple of
memory-hotplug issues. Otherwise singletons, please see the changelogs
for details"
* tag 'mm-hotfixes-stable-2026-05-18-21-07' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mm/memory: fix spurious warning when unmapping device-private/exclusive pages
mm: fix __vm_normal_page() to handle missing support for pmd_special()/pud_special()
drivers/base/memory: fix memory block reference leak in poison accounting
mm/memory_hotplug: fix memory block reference leak on remove
lib: kunit_iov_iter: fix test fail on powerpc
mm/page_alloc: fix initialization of tags of the huge zero folio with init_on_free
MAINTAINERS: add kexec@ list to LIVE UPDATE ENTRY
MAINTAINERS: add tree for KDUMP and KEXEC
selftests/mm: run_vmtests.sh: fix destructive tests invocation
scripts/gdb: slab: update field names of struct kmem_cache
scripts/gdb: mm: cast untyped symbols in x86_page_ops
mm/damon: fix damos_stat tracepoint format for sz_applied
mm/damon/sysfs-schemes: call missing mem_cgroup_iter_break()
mm/migrate_device: fix spinlock leak in migrate_vma_insert_huge_pmd_page
The package versioning scheme does not enable smooth upgrades from "rc"
releases to the corresponding stable releases (e.g. 7.0.0-rc7 -> 7.0.0)
because pacman considers that a downgrade due to the underscore in
pkgver (e.g. 7.0.0_rc7), see e.g. vercmp(8) for an explanation of the
package version comparison used by pacman. Package versions which are
derived from said releases (e.g. built from git revisions) are
similarly affected. Fix this by modifying pkgver in order to remove the
hyphen from kernel versions containing "-rcN", where N is a
non-negative integer.
Acked-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Viktor Jägersküpper <viktor_jaegerskuepper@freenet.de>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Link: https://patch.msgid.link/20260515215913.92481-1-viktor_jaegerskuepper@freenet.de
Fixes: c8578539de ("kbuild: add script and target to generate pacman package")
Signed-off-by: Nicolas Schier <nsc@kernel.org>
Several functions in scripts/mod/file2alias.c build the module alias
string by repeatedly appending into a fixed-size on-stack buffer:
char alias[256] = {};
...
sprintf(alias + strlen(alias), "%X,*", i);
This pattern is unbounded and silently corrupts the stack when the
formatted output exceeds the destination size. Two functions in this
file are realistically reachable with input that overflows their
buffer:
1. do_input_entry() appends across nine bitmap classes
(evbit/keybit/relbit/absbit/mscbit/ledbit/sndbit/ffbit/swbit). The
keybit case alone scans bits from INPUT_DEVICE_ID_KEY_MIN_INTERESTING
(0x71) to INPUT_DEVICE_ID_KEY_MAX (0x2ff), 655 iterations; if a
MODULE_DEVICE_TABLE(input, ...) populates keybit[] densely, the
emission reaches ~3132 bytes — overflowing the 256-byte buffer by
about 12x. include/linux/mod_devicetable.h declares storage for the
full bit range ("keybit[INPUT_DEVICE_ID_KEY_MAX / BITS_PER_LONG + 1]"),
so the worst case is reachable per the ABI.
2. do_dmi_entry() emits one ":<prefix>*<filtered_substr>*" segment per
matched DMI field, up to 4 matches per dmi_system_id. Each substr
is sized as char[79] in struct dmi_strmatch (mod_devicetable.h:584),
and dmi_ascii_filter() copies it verbatim into the alias buffer
without bounds. Worst case: 4 × (1 + 3 + 1 + 79 + 1) = 336 bytes
into alias[256], an 80-byte overflow.
No driver in the current tree triggers either case — every in-tree
INPUT_DEVICE_ID_MATCH_KEYBIT user populates keybit[] very sparsely
(1-3 bits), and no in-tree dmi_system_id has four maximally-long
matches. The concern is defense-in-depth: both unbounded sprintf
chains are silent stack-corruption primitives in a host build tool,
and the buffer sizes have not been revisited since the corresponding
code was first introduced.
The other do_*_entry() handlers in this file (do_usb_entry,
do_cpu_entry, do_typec_entry, ...) were audited and are bounded by
their input field sizes (uint16 IDs, fixed-length keys); their alias
buffers do not need this treatment.
Reproduced under AddressSanitizer with a stand-alone harness mirroring
do_input on a fully-populated keybit:
==18319==ERROR: AddressSanitizer: stack-buffer-overflow
WRITE of size 2 at offset 288 in frame [32, 288) 'alias'
#6 do_input poc.c:44
Stack-canary build:
Abort trap: 6 (strlen(alias)=3134, cap was 256-1)
Add a small alias_append() helper around vsnprintf with a remaining-
space check and call fatal() on overflow, matching the modpost style
for unrecoverable build conditions. do_input() takes the buffer size
as a new parameter; do_input_entry() and do_dmi_entry() pass
sizeof(alias) at every call site. dmi_ascii_filter() takes the
remaining buffer size as well and aborts on truncation. This bounds
every write into the on-stack buffers and turns the latent overflow
into a clean build error if it is ever reached.
Fixes: 1d8f430c15 ("[PATCH] Input: add modalias support")
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Hasan Basbunar <basbunarhasan@gmail.com>
Link: https://patch.msgid.link/20260505161102.44087-1-basbunarhasan@gmail.com
Signed-off-by: Nicolas Schier <nsc@kernel.org>
Steps on the way to v7.1-rc1
Resolved merge conflicts in:
include/linux/module.h
kernel/module/main.c
Cc: Siddharth Nayyar <sidnayyar@google.com>
Cc: Will McVicker <willmcvicker@google.com>
Change-Id: Ia9abf40b1600d5f67533e107e69d8c16979e2c71
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Pull Kbuild fixes from Nicolas Schier:
- builddeb - avoid recompiles for non-cross-compiles
Avoid triggering complete rebuilds for non-cross-compile Debian
package builds by only triggering the rebuild of host tools for
actual cross-compile builds
- Never respect CONFIG_WERROR / W=e to fixdep
Avoid spurious rebuilds of fixdep w/ and w/o -Werror during a single
kbuild invocation by never respecting CONFIG_WERROR for fixdep
* tag 'kbuild-fixes-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux:
kbuild: Never respect CONFIG_WERROR / W=e to fixdep
kbuild: builddeb - avoid recompiles for non-cross-compiles
Pull SPDX update from Greg KH:
"Here is a single SPDX-like change for 7.1-rc1. It explicitly allows
the use of SPDX-FileCopyrightText which has been used already in many
files.
At the same time, update checkpatch to catch any "non allowed" spdx
identifiers as we don't want to go overboard here.
This has been in linux-next for a long time with no reported problems"
* tag 'spdx-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx:
LICENSES: Explicitly allow SPDX-FileCopyrightText
Pull parisc architecture updates from Helge Deller:
- A fix to make modules on 32-bit parisc architecture work again
- Drop ip_fast_csum() inline assembly to avoid unaligned memory
accesses
- Allow to build kernel without 32-bit VDSO
- Reference leak fix in error path in LED driver
* tag 'parisc-for-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: led: fix reference leak on failed device registration
module.lds.S: Fix modules on 32-bit parisc architecture
parisc: Allow to build without VDSO32
parisc: Include 32-bit VDSO only when building for 32-bit or compat mode
parisc: Allow to disable COMPAT mode on 64-bit kernel
parisc: Fix default stack size when COMPAT=n
parisc: Fix signal code to depend on CONFIG_COMPAT instead of CONFIG_64BIT
parisc: is_compat_task() shall return false for COMPAT=n
parisc: Avoid compat syscalls when COMPAT=n
parisc: _llseek syscall is only available for 32-bit userspace
parisc: Drop ip_fast_csum() inline assembly implementation
parisc: update outdated comments for renamed ccio_alloc_consistent()
On the 32-bit parisc architecture, we always used the
-ffunction-sections compiler option to tell the compiler to put the
functions into seperate text sections. This is necessary, otherwise
"big" kernel modules like ext4 or ipv6 fail to load because some
branches won't be able to reach their stubs.
Commit 1ba9f89794 ("vmlinux.lds: Unify TEXT_MAIN, DATA_MAIN, and related
macros") broke this for parisc because all text sections will get
unconditionally merged now.
Introduce the ARCH_WANTS_MODULES_TEXT_SECTIONS config option which
avoids the text section merge for modules, and fix this issue by
enabling this option by default for 32-bit parisc.
Fixes: 1ba9f89794 ("vmlinux.lds: Unify TEXT_MAIN, DATA_MAIN, and related macros")
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: stable@vger.kernel.org # v6.19+
Suggested-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Helge Deller <deller@gmx.de>
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
...
Limit checkpatch warnings for normally-const structs by excluding patterns
consistent with forward declarations.
For example, the forward declaration `struct regmap_access_table;` in a
header file currently generates a warning recommending that it is
generally declared as const; however, this would apply a useless type
qualifier in the empty declaration `const struct regmap_access_table;`,
and subsequently generate compiler warnings.
Link: https://lkml.kernel.org/r/20260331181509.1258693-1-tknelms@google.com
Signed-off-by: Taylor Nelms <tknelms@google.com>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Pull bpf updates from Alexei Starovoitov:
- Welcome new BPF maintainers: Kumar Kartikeya Dwivedi, Eduard
Zingerman while Martin KaFai Lau reduced his load to Reviwer.
- Lots of fixes everywhere from many first time contributors. Thank you
All.
- Diff stat is dominated by mechanical split of verifier.c into
multiple components:
- backtrack.c: backtracking logic and jump history
- states.c: state equivalence
- cfg.c: control flow graph, postorder, strongly connected
components
- liveness.c: register and stack liveness
- fixups.c: post-verification passes: instruction patching, dead
code removal, bpf_loop inlining, finalize fastcall
8k line were moved. verifier.c still stands at 20k lines.
Further refactoring is planned for the next release.
- Replace dynamic stack liveness with static stack liveness based on
data flow analysis.
This improved the verification time by 2x for some programs and
equally reduced memory consumption. New logic is in liveness.c and
supported by constant folding in const_fold.c (Eduard Zingerman,
Alexei Starovoitov)
- Introduce BTF layout to ease addition of new BTF kinds (Alan Maguire)
- Use kmalloc_nolock() universally in BPF local storage (Amery Hung)
- Fix several bugs in linked registers delta tracking (Daniel Borkmann)
- Improve verifier support of arena pointers (Emil Tsalapatis)
- Improve verifier tracking of register bounds in min/max and tnum
domains (Harishankar Vishwanathan, Paul Chaignon, Hao Sun)
- Further extend support for implicit arguments in the verifier (Ihor
Solodrai)
- Add support for nop,nop5 instruction combo for USDT probes in libbpf
(Jiri Olsa)
- Support merging multiple module BTFs (Josef Bacik)
- Extend applicability of bpf_kptr_xchg (Kaitao Cheng)
- Retire rcu_trace_implies_rcu_gp() (Kumar Kartikeya Dwivedi)
- Support variable offset context access for 'syscall' programs (Kumar
Kartikeya Dwivedi)
- Migrate bpf_task_work and dynptr to kmalloc_nolock() (Mykyta
Yatsenko)
- Fix UAF in in open-coded task_vma iterator (Puranjay Mohan)
* tag 'bpf-next-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (241 commits)
selftests/bpf: cover short IPv4/IPv6 inputs with adjust_room
bpf: reject short IPv4/IPv6 inputs in bpf_prog_test_run_skb
selftests/bpf: Use memfd_create instead of shm_open in cgroup_iter_memcg
selftests/bpf: Add test for cgroup storage OOB read
bpf: Fix OOB in pcpu_init_value
selftests/bpf: Fix reg_bounds to match new tnum-based refinement
selftests/bpf: Add tests for non-arena/arena operations
bpf: Allow instructions with arena source and non-arena dest registers
bpftool: add missing fsession to the usage and docs of bpftool
docs/bpf: add missing fsession attach type to docs
bpf: add missing fsession to the verifier log
bpf: Move BTF checking logic into check_btf.c
bpf: Move backtracking logic to backtrack.c
bpf: Move state equivalence logic to states.c
bpf: Move check_cfg() into cfg.c
bpf: Move compute_insn_live_regs() into liveness.c
bpf: Move fixup/post-processing logic from verifier.c into fixups.c
bpf: Simplify do_check_insn()
bpf: Move checks for reserved fields out of the main pass
bpf: Delete unused variable
...
Pull module updates from Sami Tolvanen:
"Kernel symbol flags:
- Replace the separate *_gpl symbol sections (__ksymtab_gpl and
__kcrctab_gpl) with a unified symbol table and a new __kflagstab
section.
This section stores symbol flags, such as the GPL-only flag, as an
8-bit bitset for each exported symbol. This is a cleanup that
simplifies symbol lookup in the module loader by avoiding table
fragmentation and will allow a cleaner way to add more flags later
if needed.
Module signature UAPI:
- Move struct module_signature to the UAPI headers to allow reuse by
tools outside the kernel proper, such as kmod and
scripts/sign-file.
This also renames a few constants for clarity and drops unused
signature types as preparation for hash-based module integrity
checking work that's in progress.
Sysfs:
- Add a /sys/module/<module>/import_ns sysfs attribute to show the
symbol namespaces imported by loaded modules.
This makes it easier to verify driver API access at runtime on
systems that care about such things (e.g. Android).
Cleanups and fixes:
- Force sh_addr to 0 for all sections in module.lds. This prevents
non-zero section addresses when linking modules with 'ld.bfd -r',
which confused elfutils.
- Fix a memory leak of charp module parameters on module unload when
the kernel is configured with CONFIG_SYSFS=n.
- Override the -EEXIST error code returned by module_init() to
userspace. This prevents confusion with the errno reserved by the
module loader to indicate that a module is already loaded.
- Simplify the warning message and drop the stack dump on positive
returns from module_init().
- Drop unnecessary extern keywords from function declarations and
synchronize parse_args() arguments with their implementation"
* tag 'modules-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux: (23 commits)
module: Simplify warning on positive returns from module_init()
module: Override -EEXIST module return
documentation: remove references to *_gpl sections
module: remove *_gpl sections from vmlinux and modules
module: deprecate usage of *_gpl sections in module loader
module: use kflagstab instead of *_gpl sections
module: populate kflagstab in modpost
module: add kflagstab section to vmlinux and modules
module: define ksym_flags enumeration to represent kernel symbol flags
selftests/bpf: verify_pkcs7_sig: Use 'struct module_signature' from the UAPI headers
sign-file: use 'struct module_signature' from the UAPI headers
tools uapi headers: add linux/module_signature.h
module: Move 'struct module_signature' to UAPI
module: Give MODULE_SIG_STRING a more descriptive name
module: Give 'enum pkey_id_type' a more specific name
module: Drop unused signature types
extract-cert: drop unused definition of PKEY_ID_PKCS7
docs: symbol-namespaces: mention sysfs attribute
module: expose imported namespaces via sysfs
module: Remove extern keyword from param prototypes
...
Pull objtool updates from Ingo Molnar:
- KLP support updates and fixes (Song Liu)
- KLP-build script updates and fixes (Joe Lawrence)
- Support Clang RAX DRAP sequence, to address clang false positive
(Josh Poimboeuf)
- Reorder ORC register numbering to match regular x86 register
numbering (Josh Poimboeuf)
- Misc cleanups (Wentong Tian, Song Liu)
* tag 'objtool-core-2026-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool/x86: Reorder ORC register numbering
objtool: Support Clang RAX DRAP sequence
livepatch/klp-build: report patch validation fuzz
livepatch/klp-build: add terminal color output
livepatch/klp-build: provide friendlier error messages
livepatch/klp-build: improve short-circuit validation
livepatch/klp-build: fix shellcheck complaints
livepatch/klp-build: add Makefile with check target
livepatch/klp-build: add grep-override function
livepatch/klp-build: switch to GNU patch and recountdiff
livepatch/klp-build: support patches that add/remove files
objtool/klp: Correlate locals to globals
objtool/klp: Match symbols based on demangled_name for global variables
objtool/klp: Remove .llvm suffix in demangle_name()
objtool/klp: Also demangle global objects
objtool/klp: Use sym->demangled_name for symbol_name hash
objtool/klp: Remove trailing '_' in demangle_name()
objtool/klp: Remove redundant strcmp() in correlate_symbols()
objtool: Use section/symbol type helpers
Pull locking updates from Ingo Molnar:
"Mutexes:
- Add killable flavor to guard definitions (Davidlohr Bueso)
- Remove the list_head from struct mutex (Matthew Wilcox)
- Rename mutex_init_lockep() (Davidlohr Bueso)
rwsems:
- Remove the list_head from struct rw_semaphore and
replace it with a single pointer (Matthew Wilcox)
- Fix logic error in rwsem_del_waiter() (Andrei Vagin)
Semaphores:
- Remove the list_head from struct semaphore (Matthew Wilcox)
Jump labels:
- Use ATOMIC_INIT() for initialization of .enabled (Thomas Weißschuh)
- Remove workaround for old compilers in initializations
(Thomas Weißschuh)
Lock context analysis changes and improvements:
- Add context analysis for rwsems (Peter Zijlstra)
- Fix rwlock and spinlock lock context annotations (Bart Van Assche)
- Fix rwlock support in <linux/spinlock_up.h> (Bart Van Assche)
- Add lock context annotations in the spinlock implementation
(Bart Van Assche)
- signal: Fix the lock_task_sighand() annotation (Bart Van Assche)
- ww-mutex: Fix the ww_acquire_ctx function annotations
(Bart Van Assche)
- Add lock context support in do_raw_{read,write}_trylock()
(Bart Van Assche)
- arm64, compiler-context-analysis: Permit alias analysis through
__READ_ONCE() with CONFIG_LTO=y (Marco Elver)
- Add __cond_releases() (Peter Zijlstra)
- Add context analysis for mutexes (Peter Zijlstra)
- Add context analysis for rtmutexes (Peter Zijlstra)
- Convert futexes to compiler context analysis (Peter Zijlstra)
Rust integration updates:
- Add atomic fetch_sub() implementation (Andreas Hindborg)
- Refactor various rust_helper_ methods for expansion (Boqun Feng)
- Add Atomic<*{mut,const} T> support (Boqun Feng)
- Add atomic operation helpers over raw pointers (Boqun Feng)
- Add performance-optimal Flag type for atomic booleans, to avoid
slow byte-sized RMWs on architectures that don't support them.
(FUJITA Tomonori)
- Misc cleanups and fixes (Andreas Hindborg, Boqun Feng, FUJITA
Tomonori)
LTO support updates:
- arm64: Optimize __READ_ONCE() with CONFIG_LTO=y (Marco Elver)
- compiler: Simplify generic RELOC_HIDE() (Marco Elver)
Miscellaneous fixes and cleanups by Peter Zijlstra, Randy Dunlap,
Thomas Weißschuh, Davidlohr Bueso and Mikhail Gavrilov"
* tag 'locking-core-2026-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits)
compiler: Simplify generic RELOC_HIDE()
locking: Add lock context annotations in the spinlock implementation
locking: Add lock context support in do_raw_{read,write}_trylock()
locking: Fix rwlock support in <linux/spinlock_up.h>
lockdep: Raise default stack trace limits when KASAN is enabled
cleanup: Optimize guards
jump_label: remove workaround for old compilers in initializations
jump_label: use ATOMIC_INIT() for initialization of .enabled
futex: Convert to compiler context analysis
locking/rwsem: Fix logic error in rwsem_del_waiter()
locking/rwsem: Add context analysis
locking/rtmutex: Add context analysis
locking/mutex: Add context analysis
compiler-context-analysys: Add __cond_releases()
locking/mutex: Remove the list_head from struct mutex
locking/semaphore: Remove the list_head from struct semaphore
locking/rwsem: Remove the list_head from struct rw_semaphore
rust: atomic: Update a safety comment in impl of `fetch_add()`
rust: sync: atomic: Update documentation for `fetch_add()`
rust: sync: atomic: Add fetch_sub()
...
Pull timer core updates from Thomas Gleixner:
- A rework of the hrtimer subsystem to reduce the overhead for
frequently armed timers, especially the hrtick scheduler timer:
- Better timer locality decision
- Simplification of the evaluation of the first expiry time by
keeping track of the neighbor timers in the RB-tree by providing
a RB-tree variant with neighbor links. That avoids walking the
RB-tree on removal to find the next expiry time, but even more
important allows to quickly evaluate whether a timer which is
rearmed changes the position in the RB-tree with the modified
expiry time or not. If not, the dequeue/enqueue sequence which
both can end up in rebalancing can be completely avoided.
- Deferred reprogramming of the underlying clock event device. This
optimizes for the situation where a hrtimer callback sets the
need resched bit. In that case the code attempts to defer the
re-programming of the clock event device up to the point where
the scheduler has picked the next task and has the next hrtick
timer armed. In case that there is no immediate reschedule or
soft interrupts have to be handled before reaching the reschedule
point in the interrupt entry code the clock event is reprogrammed
in one of those code paths to prevent that the timer becomes
stale.
- Support for clocksource coupled clockevents
The TSC deadline timer is coupled to the TSC. The next event is
programmed in TSC time. Currently this is done by converting the
CLOCK_MONOTONIC based expiry value into a relative timeout,
converting it into TSC ticks, reading the TSC adding the delta
ticks and writing the deadline MSR.
As the timekeeping core has the conversion factors for the TSC
already, the whole back and forth conversion can be completely
avoided. The timekeeping core calculates the reverse conversion
factors from nanoseconds to TSC ticks and utilizes the base
timestamps of TSC and CLOCK_MONOTONIC which are updated once per
tick. This allows a direct conversion into the TSC deadline value
without reading the time and as a bonus keeps the deadline
conversion in sync with the TSC conversion factors, which are
updated by adjtimex() on systems with NTP/PTP enabled.
- Allow inlining of the clocksource read and clockevent write
functions when they are tiny enough, e.g. on x86 RDTSC and WRMSR.
With all those enhancements in place a hrtick enabled scheduler
provides the same performance as without hrtick. But also other
hrtimer users obviously benefit from these optimizations.
- Robustness improvements and cleanups of historical sins in the
hrtimer and timekeeping code.
- Rewrite of the clocksource watchdog.
The clocksource watchdog code has over time reached the state of an
impenetrable maze of duct tape and staples. The original design,
which was made in the context of systems far smaller than today, is
based on the assumption that the to be monitored clocksource (TSC)
can be trivially compared against a known to be stable clocksource
(HPET/ACPI-PM timer).
Over the years this rather naive approach turned out to have major
flaws. Long delays between the watchdog invocations can cause wrap
arounds of the reference clocksource. The access to the reference
clocksource degrades on large multi-sockets systems dure to
interconnect congestion. This has been addressed with various
heuristics which degraded the accuracy of the watchdog to the point
that it fails to detect actual TSC problems on older hardware which
exposes slow inter CPU drifts due to firmware manipulating the TSC to
hide SMI time.
The rewrite addresses this by:
- Restricting the validation against the reference clocksource to
the boot CPU which is usually closest to the legacy block which
contains the reference clocksource (HPET/ACPI-PM).
- Do a round robin validation betwen the boot CPU and the other
CPUs based only on the TSC with an algorithm similar to the TSC
synchronization code during CPU hotplug.
- Being more leniant versus remote timeouts
- The usual tiny fixes, cleanups and enhancements all over the place
* tag 'timers-core-2026-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (75 commits)
alarmtimer: Access timerqueue node under lock in suspend
hrtimer: Fix incorrect #endif comment for BITS_PER_LONG check
posix-timers: Fix stale function name in comment
timers: Get this_cpu once while clearing the idle state
clocksource: Rewrite watchdog code completely
clocksource: Don't use non-continuous clocksources as watchdog
x86/tsc: Handle CLOCK_SOURCE_VALID_FOR_HRES correctly
MIPS: Don't select CLOCKSOURCE_WATCHDOG
parisc: Remove unused clocksource flags
hrtimer: Add a helper to retrieve a hrtimer from its timerqueue node
hrtimer: Remove trailing comma after HRTIMER_MAX_CLOCK_BASES
hrtimer: Mark index and clockid of clock base as const
hrtimer: Drop unnecessary pointer indirection in hrtimer_expire_entry event
hrtimer: Drop spurious space in 'enum hrtimer_base_type'
hrtimer: Don't zero-initialize ret in hrtimer_nanosleep()
hrtimer: Remove hrtimer_get_expires_ns()
timekeeping: Mark offsets array as const
timekeeping/auxclock: Consistently use raw timekeeper for tk_setup_internals()
timer_list: Print offset as signed integer
tracing: Use explicit array size instead of sentinel elements in symbol printing
...
Pull Kbuild/Kconfig updates from Nicolas Schier:
"Kbuild:
- reject unexpected values for LLVM=
- uapi: remove usage of toolchain headers
- switch from '-fms-extensions' to '-fms-anonymous-structs' when
available (currently: clang >= 23.0.0)
- reduce the number of compiler-generated suffixes for clang thin-lto
build
- reduce output spam ("GEN Makefile") when building out of tree
- improve portability for testing headers
- also test UAPI headers against C++ compilers
- drop build ID architecture allow-list in vdso_install
- only run checksyscalls when necessary
- update the debug information notes in reproducible-builds.rst
- expand inlining hints with -fdiagnostics-show-inlining-chain
Kconfig:
- forbid multiple entries with the same symbol in a choice
- error out on duplicated kconfig inclusion"
* tag 'kbuild-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux: (35 commits)
kbuild: expand inlining hints with -fdiagnostics-show-inlining-chain
kconfig: forbid multiple entries with the same symbol in a choice
Documentation: kbuild: Update the debug information notes in reproducible-builds.rst
checksyscalls: move instance functionality into generic code
checksyscalls: only run when necessary
checksyscalls: fail on all intermediate errors
checksyscalls: move path to reference table to a variable
kbuild: vdso_install: drop build ID architecture allow-list
kbuild: vdso_install: gracefully handle images without build ID
kbuild: vdso_install: hide readelf warnings
kbuild: vdso_install: split out the readelf invocation
kbuild: uapi: also test UAPI headers against C++ compilers
kbuild: uapi: provide a C++ compatible dummy definition of NULL
kbuild: uapi: handle UML in architecture-specific exclusion lists
kbuild: uapi: move all include path flags together
kbuild: uapi: move some compiler arguments out of the command definition
check-uapi: use dummy libc includes
check-uapi: honor ${CROSS_COMPILE} setting
check-uapi: link into shared objects
kbuild: reduce output spam when building out of tree
...