It's misplaced in struct proc_ns_operations and ns->ops might be NULL if
the namespace is compiled out but we still want to know the type of the
namespace for the initial namespace struct.
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
The kernel's CFI implementation uses the KCFI ABI specifically, and is
not strictly tied to a particular compiler. In preparation for GCC
supporting KCFI, rename CONFIG_CFI_CLANG to CONFIG_CFI (along with
associated options).
Use new "transitional" Kconfig option for old CONFIG_CFI_CLANG that will
enable CONFIG_CFI during olddefconfig.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20250923213422.1105654-3-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
clang < 17 fails to use scope local labels with CONFIG_CC_HAS_ASM_GOTO_OUTPUT=y:
{
__label__ local_lbl;
...
unsafe_get_user(uval, uaddr, local_lbl);
...
return 0;
local_lbl:
return -EFAULT;
}
when two such scopes exist in the same function:
error: cannot jump from this asm goto statement to one of its possible targets
There are other failure scenarios. Shuffling code around slightly makes it
worse and fail even with one instance.
That issue prevents using local labels for a cleanup based user access
mechanism.
After failed attempts to provide a simple enough test case for the 'depends
on' test in Kconfig, the initial cure was to mark ASM goto broken on clang
versions < 17 to get this road block out of the way.
But Nathan pointed out that this is a known clang issue and indeed affects
clang < version 17 in combination with cleanup(). It's not even required to
use local labels for that.
The clang issue tracker has a small enough test case, which can be used as
a test in the 'depends on' section of CC_HAS_ASM_GOTO_OUTPUT:
void bar(void **);
void* baz(void);
int foo (void) {
{
asm goto("jmp %l0"::::l0);
return 0;
l0:
return 1;
}
void *x __attribute__((cleanup(bar))) = baz();
{
asm goto("jmp %l0"::::l1);
return 42;
l1:
return 0xff;
}
}
Add another dependency to config CC_HAS_ASM_GOTO_OUTPUT for it and use the
clang issue tracker test case for detection by condensing it to obfuscated
C-code contest format. This reliably catches the problem on clang < 17 and
did not show any issues on the non broken GCC versions.
That test might be sufficient to catch all issues and therefore could
replace the existing test, but keeping that around does no harm either.
Thanks to Nathan for pointing to the relevant clang issue!
Suggested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://github.com/ClangBuiltLinux/linux/issues/1886
Link: f023f5cdb2
Commit bd7c231212 ("pinctrl: meson: Fix typo in device table macro")
is needed in kbuild-next to avoid a build error with a future change.
While at it, address the conflict between commit 41f9049cff ("riscv:
Only allow LTO with CMODEL_MEDANY") and commit 6578a1ff6a ("riscv:
Remove version check for LTO_CLANG selects"), as reported by Stephen
Rothwell [1].
Link: https://lore.kernel.org/20250908134913.68778b7b@canb.auug.org.au/ [1]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Support the generic ns lookup infrastructure to support file handles for
namespaces.
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Make the statement attribute "assume" with a new __assume macro available.
The assume attribute is used to indicate that a certain condition is
assumed to be true. Compilers may or may not use this indication to
generate optimized code. If this condition is violated at runtime, the
behavior is undefined.
Note that the clang documentation states that optimizers may react
differently to this attribute, and this may even have a negative
performance impact. Therefore this attribute should be used with care.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
INITRAMFS_PRESERVE_MTIME is only used in init/initramfs.c and
init/initramfs_test.c. Hence add a dependency on BLK_DEV_INITRD, to
prevent asking the user about this feature when configuring a kernel
without initramfs support.
Fixes: 1274aea127 ("initramfs: add INITRAMFS_PRESERVE_MTIME Kconfig option")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Martin Wilck <mwilck@suse.com>
Reviewed-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Add the local variable 'nr_disks' and replace the manual ternary "s"
pluralization with the standardized str_plural() helper function.
Use pr_notice() instead of printk(KERN_NOTICE) to silence a checkpatch
warning.
No functional changes intended.
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Use struct_size() to calculate the number of bytes to allocate for a new
directory entry. No functional changes.
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Christian Brauner <brauner@kernel.org>
The local variables 'rotator' and 'rotate' (used for the progress
indicator) aren't used on s390. Building the kernel with W=1 generates
the following warning:
init/do_mounts_rd.c:192:17: warning: variable 'rotate' set but not used [-Wunused-but-set-variable]
192 | unsigned short rotate = 0;
| ^
1 warning generated.
Remove the preprocessor directives and use the IS_ENABLED(CONFIG_S390)
macro instead, allowing the compiler to optimize away unused variables
and avoid the warning on s390.
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Pull misc fixes from Andrew Morton:
"20 hotfixes. 15 are cc:stable and the remainder address post-6.16
issues or aren't considered necessary for -stable kernels. 14 of these
fixes are for MM.
This includes
- kexec fixes from Breno for a recently introduced
use-uninitialized bug
- DAMON fixes from Quanmin Yan to avoid div-by-zero crashes
which can occur if the operator uses poorly-chosen insmod
parameters
and misc singleton fixes"
* tag 'mm-hotfixes-stable-2025-09-10-20-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
MAINTAINERS: add tree entry to numa memblocks and emulation block
mm/damon/sysfs: fix use-after-free in state_show()
proc: fix type confusion in pde_set_flags()
compiler-clang.h: define __SANITIZE_*__ macros only when undefined
mm/vmalloc, mm/kasan: respect gfp mask in kasan_populate_vmalloc()
ocfs2: fix recursive semaphore deadlock in fiemap call
mm/memory-failure: fix VM_BUG_ON_PAGE(PagePoisoned(page)) when unpoison memory
mm/mremap: fix regression in vrm->new_addr check
percpu: fix race on alloc failed warning limit
mm/memory-failure: fix redundant updates for already poisoned pages
s390: kexec: initialize kexec_buf struct
riscv: kexec: initialize kexec_buf struct
arm64: kexec: initialize kexec_buf struct in load_other_segments()
mm/damon/reclaim: avoid divide-by-zero in damon_reclaim_apply_parameters()
mm/damon/lru_sort: avoid divide-by-zero in damon_lru_sort_apply_parameters()
mm/damon/core: set quota->charged_from to jiffies at first charge window
mm/hugetlb: add missing hugetlb_lock in __unmap_hugepage_range()
init/main.c: fix boot time tracing crash
mm/memory_hotplug: fix hwpoisoned large folio handling in do_migrate_range()
mm/khugepaged: fix the address passed to notifier on testing young
The static usage pattern of creating a cgroup, enabling controllers,
and then seeding it with CLONE_INTO_CGROUP doesn't require write
locking cgroup_threadgroup_rwsem and thus doesn't benefit from this
patch.
To avoid affecting other users, the per threadgroup rwsem is only used
when the favordynmods is enabled.
As computer hardware advances, modern systems are typically equipped
with many CPU cores and large amounts of memory, enabling the deployment
of numerous applications. On such systems, container creation and
deletion become frequent operations, making cgroup process migration no
longer a cold path. This leads to noticeable contention with common
process operations such as fork, exec, and exit.
To alleviate the contention between cgroup process migration and
operations like process fork, this patch modifies lock to take the write
lock on signal_struct->group_rwsem when writing pid to
cgroup.procs/threads instead of holding a global write lock.
Cgroup process migration has historically relied on
signal_struct->group_rwsem to protect thread group integrity. In commit
<1ed1328792ff> ("sched, cgroup: replace signal_struct->group_rwsem with
a global percpu_rwsem"), this was changed to a global
cgroup_threadgroup_rwsem. The advantage of using a global lock was
simplified handling of process group migrations. This patch retains the
use of the global lock for protecting process group migration, while
reducing contention by using per thread group lock during
cgroup.procs/threads writes.
The locking behavior is as follows:
write cgroup.procs/threads | process fork,exec,exit | process group migration
------------------------------------------------------------------------------
cgroup_lock() | down_read(&g_rwsem) | cgroup_lock()
down_write(&p_rwsem) | down_read(&p_rwsem) | down_write(&g_rwsem)
critical section | critical section | critical section
up_write(&p_rwsem) | up_read(&p_rwsem) | up_write(&g_rwsem)
cgroup_unlock() | up_read(&g_rwsem) | cgroup_unlock()
g_rwsem denotes cgroup_threadgroup_rwsem, p_rwsem denotes
signal_struct->group_rwsem.
This patch eliminates contention between cgroup migration and fork
operations for threads that belong to different thread groups, thereby
reducing the long-tail latency of cgroup migrations and lowering system
load.
With this patch, under heavy fork and exec interference, the long-tail
latency of cgroup migration has been reduced from milliseconds to
microseconds. Under heavy cgroup migration interference, the multi-CPU
score of the spawn test case in UnixBench increased by 9%.
tj: Update comment in cgroup_favor_dynmods() and switch WARN_ONCE() to
pr_warn_once().
Signed-off-by: Yi Tao <escape@linux.alibaba.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Pull rust fixes from Miguel Ojeda:
- Two changes to prepare for the future Rust 1.91.0 release (expected
2025-10-30, currently in nightly): a target specification format
change and a renamed, soon-to-be-stabilized 'core' function.
* tag 'rust-fixes-6.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux:
rust: support Rust >= 1.91.0 target spec
rust: use the new name Location::file_as_c_str() in Rust >= 1.91.0
After an innocuous change in -next that modified a structure that
contains __counted_by, clang-19 start crashing when building certain
files in drivers/gpu/drm/xe. When assertions are enabled, the more
descriptive failure is:
clang: clang/lib/AST/RecordLayoutBuilder.cpp:3335: const ASTRecordLayout &clang::ASTContext::getASTRecordLayout(const RecordDecl *) const: Assertion `D && "Cannot get layout of forward declarations!"' failed.
According to a reverse bisect, a tangential change to the LLVM IR
generation phase of clang during the LLVM 20 development cycle [1]
resolves this problem. Bump the version of clang that enables
CONFIG_CC_HAS_COUNTED_BY to 20.1.0 to ensure that this issue cannot be
hit.
Link: 160fb1121c [1]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Justin Stitt <justinstitt@google.com>
Link: https://lore.kernel.org/r/20250807-fix-counted_by-clang-19-v1-1-902c86c1d515@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
Pull non-MM updates from Andrew Morton:
"Significant patch series in this pull request:
- "squashfs: Remove page->mapping references" (Matthew Wilcox) gets
us closer to being able to remove page->mapping
- "relayfs: misc changes" (Jason Xing) does some maintenance and
minor feature addition work in relayfs
- "kdump: crashkernel reservation from CMA" (Jiri Bohac) switches
us from static preallocation of the kdump crashkernel's working
memory over to dynamic allocation. So the difficulty of a-priori
estimation of the second kernel's needs is removed and the first
kernel obtains extra memory
- "generalize panic_print's dump function to be used by other
kernel parts" (Feng Tang) implements some consolidation and
rationalization of the various ways in which a failing kernel
splats information at the operator
* tag 'mm-nonmm-stable-2025-08-03-12-47' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (80 commits)
tools/getdelays: add backward compatibility for taskstats version
kho: add test for kexec handover
delaytop: enhance error logging and add PSI feature description
samples: Kconfig: fix spelling mistake "instancess" -> "instances"
fat: fix too many log in fat_chain_add()
scripts/spelling.txt: add notifer||notifier to spelling.txt
xen/xenbus: fix typo "notifer"
net: mvneta: fix typo "notifer"
drm/xe: fix typo "notifer"
cxl: mce: fix typo "notifer"
KVM: x86: fix typo "notifer"
MAINTAINERS: add maintainers for delaytop
ucount: use atomic_long_try_cmpxchg() in atomic_long_inc_below()
ucount: fix atomic_long_inc_below() argument type
kexec: enable CMA based contiguous allocation
stackdepot: make max number of pools boot-time configurable
lib/xxhash: remove unused functions
init/Kconfig: restore CONFIG_BROKEN help text
lib/raid6: update recov_rvv.c zero page usage
docs: update docs after introducing delaytop
...
Pull sched_ext updates from Tejun Heo:
- Add support for cgroup "cpu.max" interface
- Code organization cleanup so that ext_idle.c doesn't depend on the
source-file-inclusion build method of sched/
- Drop UP paths in accordance with sched core changes
- Documentation and other misc changes
* tag 'sched_ext-for-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext:
sched_ext: Fix scx_bpf_reenqueue_local() reference
sched_ext: Drop kfuncs marked for removal in 6.15
sched_ext, rcu: Eject BPF scheduler on RCU CPU stall panic
kernel/sched/ext.c: fix typo "occured" -> "occurred" in comments
sched_ext: Add support for cgroup bandwidth control interface
sched_ext, sched/core: Factor out struct scx_task_group
sched_ext: Return NULL in llc_span
sched_ext: Always use SMP versions in kernel/sched/ext_idle.h
sched_ext: Always use SMP versions in kernel/sched/ext_idle.c
sched_ext: Always use SMP versions in kernel/sched/ext.h
sched_ext: Always use SMP versions in kernel/sched/ext.c
sched_ext: Documentation: Clarify time slice handling in task lifecycle
sched_ext: Make scx_locked_rq() inline
sched_ext: Make scx_rq_bypassing() inline
sched_ext: idle: Make local functions static in ext_idle.c
sched_ext: idle: Remove unnecessary ifdef in scx_bpf_cpu_node()
Pull MM updates from Andrew Morton:
"As usual, many cleanups. The below blurbiage describes 42 patchsets.
21 of those are partially or fully cleanup work. "cleans up",
"cleanup", "maintainability", "rationalizes", etc.
I never knew the MM code was so dirty.
"mm: ksm: prevent KSM from breaking merging of new VMAs" (Lorenzo Stoakes)
addresses an issue with KSM's PR_SET_MEMORY_MERGE mode: newly
mapped VMAs were not eligible for merging with existing adjacent
VMAs.
"mm/damon: introduce DAMON_STAT for simple and practical access monitoring" (SeongJae Park)
adds a new kernel module which simplifies the setup and usage of
DAMON in production environments.
"stop passing a writeback_control to swap/shmem writeout" (Christoph Hellwig)
is a cleanup to the writeback code which removes a couple of
pointers from struct writeback_control.
"drivers/base/node.c: optimization and cleanups" (Donet Tom)
contains largely uncorrelated cleanups to the NUMA node setup and
management code.
"mm: userfaultfd: assorted fixes and cleanups" (Tal Zussman)
does some maintenance work on the userfaultfd code.
"Readahead tweaks for larger folios" (Ryan Roberts)
implements some tuneups for pagecache readahead when it is reading
into order>0 folios.
"selftests/mm: Tweaks to the cow test" (Mark Brown)
provides some cleanups and consistency improvements to the
selftests code.
"Optimize mremap() for large folios" (Dev Jain)
does that. A 37% reduction in execution time was measured in a
memset+mremap+munmap microbenchmark.
"Remove zero_user()" (Matthew Wilcox)
expunges zero_user() in favor of the more modern memzero_page().
"mm/huge_memory: vmf_insert_folio_*() and vmf_insert_pfn_pud() fixes" (David Hildenbrand)
addresses some warts which David noticed in the huge page code.
These were not known to be causing any issues at this time.
"mm/damon: use alloc_migrate_target() for DAMOS_MIGRATE_{HOT,COLD" (SeongJae Park)
provides some cleanup and consolidation work in DAMON.
"use vm_flags_t consistently" (Lorenzo Stoakes)
uses vm_flags_t in places where we were inappropriately using other
types.
"mm/memfd: Reserve hugetlb folios before allocation" (Vivek Kasireddy)
increases the reliability of large page allocation in the memfd
code.
"mm: Remove pXX_devmap page table bit and pfn_t type" (Alistair Popple)
removes several now-unneeded PFN_* flags.
"mm/damon: decouple sysfs from core" (SeongJae Park)
implememnts some cleanup and maintainability work in the DAMON
sysfs layer.
"madvise cleanup" (Lorenzo Stoakes)
does quite a lot of cleanup/maintenance work in the madvise() code.
"madvise anon_name cleanups" (Vlastimil Babka)
provides additional cleanups on top or Lorenzo's effort.
"Implement numa node notifier" (Oscar Salvador)
creates a standalone notifier for NUMA node memory state changes.
Previously these were lumped under the more general memory
on/offline notifier.
"Make MIGRATE_ISOLATE a standalone bit" (Zi Yan)
cleans up the pageblock isolation code and fixes a potential issue
which doesn't seem to cause any problems in practice.
"selftests/damon: add python and drgn based DAMON sysfs functionality tests" (SeongJae Park)
adds additional drgn- and python-based DAMON selftests which are
more comprehensive than the existing selftest suite.
"Misc rework on hugetlb faulting path" (Oscar Salvador)
fixes a rather obscure deadlock in the hugetlb fault code and
follows that fix with a series of cleanups.
"cma: factor out allocation logic from __cma_declare_contiguous_nid" (Mike Rapoport)
rationalizes and cleans up the highmem-specific code in the CMA
allocator.
"mm/migration: rework movable_ops page migration (part 1)" (David Hildenbrand)
provides cleanups and future-preparedness to the migration code.
"mm/damon: add trace events for auto-tuned monitoring intervals and DAMOS quota" (SeongJae Park)
adds some tracepoints to some DAMON auto-tuning code.
"mm/damon: fix misc bugs in DAMON modules" (SeongJae Park)
does that.
"mm/damon: misc cleanups" (SeongJae Park)
also does what it claims.
"mm: folio_pte_batch() improvements" (David Hildenbrand)
cleans up the large folio PTE batching code.
"mm/damon/vaddr: Allow interleaving in migrate_{hot,cold} actions" (SeongJae Park)
facilitates dynamic alteration of DAMON's inter-node allocation
policy.
"Remove unmap_and_put_page()" (Vishal Moola)
provides a couple of page->folio conversions.
"mm: per-node proactive reclaim" (Davidlohr Bueso)
implements a per-node control of proactive reclaim - beyond the
current memcg-based implementation.
"mm/damon: remove damon_callback" (SeongJae Park)
replaces the damon_callback interface with a more general and
powerful damon_call()+damos_walk() interface.
"mm/mremap: permit mremap() move of multiple VMAs" (Lorenzo Stoakes)
implements a number of mremap cleanups (of course) in preparation
for adding new mremap() functionality: newly permit the remapping
of multiple VMAs when the user is specifying MREMAP_FIXED. It still
excludes some specialized situations where this cannot be performed
reliably.
"drop hugetlb_free_pgd_range()" (Anthony Yznaga)
switches some sparc hugetlb code over to the generic version and
removes the thus-unneeded hugetlb_free_pgd_range().
"mm/damon/sysfs: support periodic and automated stats update" (SeongJae Park)
augments the present userspace-requested update of DAMON sysfs
monitoring files. Automatic update is now provided, along with a
tunable to control the update interval.
"Some randome fixes and cleanups to swapfile" (Kemeng Shi)
does what is claims.
"mm: introduce snapshot_page" (Luiz Capitulino and David Hildenbrand)
provides (and uses) a means by which debug-style functions can grab
a copy of a pageframe and inspect it locklessly without tripping
over the races inherent in operating on the live pageframe
directly.
"use per-vma locks for /proc/pid/maps reads" (Suren Baghdasaryan)
addresses the large contention issues which can be triggered by
reads from that procfs file. Latencies are reduced by more than
half in some situations. The series also introduces several new
selftests for the /proc/pid/maps interface.
"__folio_split() clean up" (Zi Yan)
cleans up __folio_split()!
"Optimize mprotect() for large folios" (Dev Jain)
provides some quite large (>3x) speedups to mprotect() when dealing
with large folios.
"selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));" and some cleanup" (wang lian)
does some cleanup work in the selftests code.
"tools/testing: expand mremap testing" (Lorenzo Stoakes)
extends the mremap() selftest in several ways, including adding
more checking of Lorenzo's recently added "permit mremap() move of
multiple VMAs" feature.
"selftests/damon/sysfs.py: test all parameters" (SeongJae Park)
extends the DAMON sysfs interface selftest so that it tests all
possible user-requested parameters. Rather than the present minimal
subset"
* tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (370 commits)
MAINTAINERS: add missing headers to mempory policy & migration section
MAINTAINERS: add missing file to cgroup section
MAINTAINERS: add MM MISC section, add missing files to MISC and CORE
MAINTAINERS: add missing zsmalloc file
MAINTAINERS: add missing files to page alloc section
MAINTAINERS: add missing shrinker files
MAINTAINERS: move memremap.[ch] to hotplug section
MAINTAINERS: add missing mm_slot.h file THP section
MAINTAINERS: add missing interval_tree.c to memory mapping section
MAINTAINERS: add missing percpu-internal.h file to per-cpu section
mm/page_alloc: remove trace_mm_alloc_contig_migrate_range_info()
selftests/damon: introduce _common.sh to host shared function
selftests/damon/sysfs.py: test runtime reduction of DAMON parameters
selftests/damon/sysfs.py: test non-default parameters runtime commit
selftests/damon/sysfs.py: generalize DAMON context commit assertion
selftests/damon/sysfs.py: generalize monitoring attributes commit assertion
selftests/damon/sysfs.py: generalize DAMOS schemes commit assertion
selftests/damon/sysfs.py: test DAMOS filters commitment
selftests/damon/sysfs.py: generalize DAMOS scheme commit assertion
selftests/damon/sysfs.py: test DAMOS destinations commitment
...
Pull x86 boot updates from Ingo Molnar:
- Implement support for embedding EFI SBAT data (Secure Boot Advanced
Targeting: a secure boot image revocation facility) on x86 (Vitaly
Kuznetsov)
- Move the efi_enter_virtual_mode() initialization call from the
generic init code to x86 init code (Alexander Shishkin)
* tag 'x86-boot-2025-07-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/efi: Implement support for embedding SBAT data for x86
x86/efi: Move runtime service initialization to arch/x86
Pull scheduler updates from Ingo Molnar:
"Core scheduler changes:
- Better tracking of maximum lag of tasks in presence of different
slices duration, for better handling of lag in the fair scheduler
(Vincent Guittot)
- Clean up and standardize #if/#else/#endif markers throughout the
entire scheduler code base (Ingo Molnar)
- Make SMP unconditional: build the SMP scheduler's data structures
and logic on UP kernel too, even though they are not used, to
simplify the scheduler and remove around 200 #ifdef/[#else]/#endif
blocks from the scheduler (Ingo Molnar)
- Reorganize cgroup bandwidth control interface handling for better
interfacing with sched_ext (Tejun Heo)
Balancing:
- Bump sd->max_newidle_lb_cost when newidle balance fails (Chris
Mason)
- Remove sched_domain_topology_level::flags to simplify the code
(Prateek Nayak)
- Simplify and clean up build_sched_topology() (Li Chen)
- Optimize build_sched_topology() on large machines (Li Chen)
Real-time scheduling:
- Add initial version of proxy execution: a mechanism for
mutex-owning tasks to inherit the scheduling context of higher
priority waiters.
Currently limited to a single runqueue and conditional on
CONFIG_EXPERT, and other limitations (John Stultz, Peter Zijlstra,
Valentin Schneider)
- Deadline scheduler (Juri Lelli):
- Fix dl_servers initialization order (Juri Lelli)
- Fix DL scheduler's root domain reinitialization logic (Juri
Lelli)
- Fix accounting bugs after global limits change (Juri Lelli)
- Fix scalability regression by implementing less agressive
dl_server handling (Peter Zijlstra)
PSI:
- Improve scalability by optimizing psi_group_change() cpu_clock()
usage (Peter Zijlstra)
Rust changes:
- Make Task, CondVar and PollCondVar methods inline to avoid
unnecessary function calls (Kunwu Chan, Panagiotis Foliadis)
- Add might_sleep() support for Rust code: Rust's "#[track_caller]"
mechanism is used so that Rust's might_sleep() doesn't need to be
defined as a macro (Fujita Tomonori)
- Introduce file_from_location() (Boqun Feng)
Debugging & instrumentation:
- Make clangd usable with scheduler source code files again (Peter
Zijlstra)
- tools: Add root_domains_dump.py which dumps root domains info (Juri
Lelli)
- tools: Add dl_bw_dump.py for printing bandwidth accounting info
(Juri Lelli)
Misc cleanups & fixes:
- Remove play_idle() (Feng Lee)
- Fix check_preemption_disabled() (Sebastian Andrzej Siewior)
- Do not call __put_task_struct() on RT if pi_blocked_on is set (Luis
Claudio R. Goncalves)
- Correct the comment in place_entity() (wang wei)"
* tag 'sched-core-2025-07-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (84 commits)
sched/idle: Remove play_idle()
sched: Do not call __put_task_struct() on rt if pi_blocked_on is set
sched: Start blocked_on chain processing in find_proxy_task()
sched: Fix proxy/current (push,pull)ability
sched: Add an initial sketch of the find_proxy_task() function
sched: Fix runtime accounting w/ split exec & sched contexts
sched: Move update_curr_task logic into update_curr_se
locking/mutex: Add p->blocked_on wrappers for correctness checks
locking/mutex: Rework task_struct::blocked_on
sched: Add CONFIG_SCHED_PROXY_EXEC & boot argument to enable/disable
sched/topology: Remove sched_domain_topology_level::flags
x86/smpboot: avoid SMT domain attach/destroy if SMT is not enabled
x86/smpboot: moves x86_topology to static initialize and truncate
x86/smpboot: remove redundant CONFIG_SCHED_SMT
smpboot: introduce SDTL_INIT() helper to tidy sched topology setup
tools/sched: Add dl_bw_dump.py for printing bandwidth accounting info
tools/sched: Add root_domains_dump.py which dumps root domains info
sched/deadline: Fix accounting after global limits change
sched/deadline: Reset extra_bw to max_bw when clearing root domains
sched/deadline: Initialize dl_servers after SMP
...
Pull futex updates from Thomas Gleixner:
- Switch the reference counting to a RCU based per-CPU reference to
address a performance bottleneck vs the single instance rcuref
variant
- Make the futex selftest build on 32-bit architectures which only
support 64-bit time_t, e.g. RISCV-32
- Cleanups and improvements in selftests and futex bench
* tag 'locking-futex-2025-07-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
selftests/futex: Fix spelling mistake "Succeffuly" -> "Successfully"
selftests/futex: Define SYS_futex on 32-bit architectures with 64-bit time_t
perf bench futex: Remove support for IMMUTABLE
selftests/futex: Remove support for IMMUTABLE
futex: Remove support for IMMUTABLE
futex: Make futex_private_hash_get() static
futex: Use RCU-based per-CPU reference counting instead of rcuref_t
selftests/futex: Adapt the private hash test to RCU related changes
Pull char / misc / IIO / other driver updates from Greg KH:
"Here is the big set of char/misc/iio and other smaller driver
subsystems for 6.17-rc1. It's a big set this time around, with the
huge majority being in the iio subsystem with new drivers and dts
files being added there.
Highlights include:
- IIO driver updates, additions, and changes making more code const
and cleaning up some init logic
- bus_type constant conversion changes
- misc device test functions added
- rust miscdevice minor fixup
- unused function removals for some drivers
- mei driver updates
- mhi driver updates
- interconnect driver updates
- Android binder updates and test infrastructure added
- small cdx driver updates
- small comedi fixes
- small nvmem driver updates
- small pps driver updates
- some acrn virt driver fixes for printk messages
- other small driver updates
All of these have been in linux-next with no reported issues"
* tag 'char-misc-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (292 commits)
binder: Use seq_buf in binder_alloc kunit tests
binder: Add copyright notice to new kunit files
misc: ti_fpc202: Switch to of_fwnode_handle()
bus: moxtet: Use dev_fwnode()
pc104: move PC104 option to drivers/Kconfig
drivers: virt: acrn: Don't use %pK through printk
comedi: fix race between polling and detaching
interconnect: qcom: Add Milos interconnect provider driver
dt-bindings: interconnect: document the RPMh Network-On-Chip Interconnect in Qualcomm Milos SoC
mei: more prints with client prefix
mei: bus: use cldev in prints
bus: mhi: host: pci_generic: Add Telit FN990B40 modem support
bus: mhi: host: Detect events pointing to unexpected TREs
bus: mhi: host: pci_generic: Add Foxconn T99W696 modem
bus: mhi: host: Use str_true_false() helper
bus: mhi: host: pci_generic: Add support for EM929x and set MRU to 32768 for better performance.
bus: mhi: host: Fix endianness of BHI vector table
bus: mhi: host: pci_generic: Disable runtime PM for QDU100
bus: mhi: host: pci_generic: Fix the modem name of Foxconn T99W640
dt-bindings: interconnect: qcom,msm8998-bwmon: Allow 'nonposted-mmio'
...
Pull io_uring updates from Jens Axboe:
- Optimization to avoid reference counts on non-cloned registered
buffers. This is how these buffers were handled prior to having
cloning support, and we can still use that approach as long as the
buffers haven't been cloned to another ring.
- Cleanup and improvement for uring_cmd, where btrfs was the only user
of storing allocated data for the lifetime of the uring_cmd. Clean
that up so we can get rid of the need to do that.
- Avoid unnecessary memory copies in uring_cmd usage. This is
particularly important as a lot of uring_cmd usage necessitates the
use of 128b SQEs.
- A few updates for recv multishot, where it's now possible to add
fairness limits for limiting how much is transferred for each retry
loop. Additionally, recv multishot now supports an overall cap as
well, where once reached the multishot recv will terminate. The
latter is useful for buffer management and juggling many recv streams
at the same time.
- Add support for returning the TX timestamps via a new socket command.
This feature can work in either singleshot or multishot mode, where
the latter triggers a completion whenever new timestamps are
available. This is an alternative to using the existing error queue.
- Add support for an io_uring "mock" file, which is the start of being
able to do 100% targeted testing in terms of exercising io_uring
request handling. The idea is to have a file type that can be
anything the tester would like, and behave exactly how you want it to
behave in terms of hitting the code paths you want.
- Improve zcrx by using sgtables to de-duplicate and improve dma
address handling.
- Prep work for supporting larger pages for zcrx.
- Various little improvements and fixes.
* tag 'for-6.17/io_uring-20250728' of git://git.kernel.dk/linux: (42 commits)
io_uring/zcrx: fix leaking pages on sg init fail
io_uring/zcrx: don't leak pages on account failure
io_uring/zcrx: fix null ifq on area destruction
io_uring: fix breakage in EXPERT menu
io_uring/cmd: remove struct io_uring_cmd_data
btrfs/ioctl: store btrfs_uring_encoded_data in io_btrfs_cmd
io_uring/cmd: introduce IORING_URING_CMD_REISSUE flag
io_uring/zcrx: account area memory
io_uring: export io_[un]account_mem
io_uring/net: Support multishot receive len cap
io_uring: deduplicate wakeup handling
io_uring/net: cast min_not_zero() type
io_uring/poll: cleanup apoll freeing
io_uring/net: allow multishot receive per-invocation cap
io_uring/net: move io_sr_msg->retry_flags to io_sr_msg->flags
io_uring/net: use passed in 'len' in io_recv_buf_select()
io_uring/zcrx: prepare fallback for larger pages
io_uring/zcrx: assert area type in io_zcrx_iov_page
io_uring/zcrx: allocate sgtable for umem areas
io_uring/zcrx: introduce io_populate_area_dma
...
The vmstat_text array contains labels for counters displayed in
/proc/vmstat. It is important to keep the labels in sync with the
counters.
There is a BUILD_BUG_ON() check in vmstat_start() that ensures the size of
the vmstat_text is not smaller than VM_EVENT_COUNTERS. This helps to
catch cases where a new counter is added but the label is not. However,
it does not help if a counter is removed but the label remains.
It would be nice to make the BUILD_BUG_ON() check more strict to catch
such cases. However, when compiling with MEMCG enabled but
VM_EVENT_COUNTERS disabled, the vmstat_text array is larger than
NR_VMSTAT_ITEMS.
This issue arises because some elements of the vmstat_text array are
present when either MEMCG or VM_EVENT_COUNTERS is enabled, but
NR_VMSTAT_ITEMS only accounts for these elements if VM_EVENT_COUNTERS is
enabled.
Instead of adjusting the NR_VMSTAT_ITEMS definition to account for MEMCG,
make MEMCG select VM_EVENT_COUNTERS. VM_EVENT_COUNTERS is enabled in most
configurations anyway.
Link: https://lkml.kernel.org/r/20250604095111.533783-1-kirill.shutemov@linux.intel.com
Fixes: ebc5d83d04 ("mm/memcontrol: use vmstat names for printing statistics")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The use of rcuref_t for reference counting introduces a performance bottleneck
when accessed concurrently by multiple threads during futex operations.
Replace rcuref_t with special crafted per-CPU reference counters. The
lifetime logic remains the same.
The newly allocate private hash starts in FR_PERCPU state. In this state, each
futex operation that requires the private hash uses a per-CPU counter (an
unsigned int) for incrementing or decrementing the reference count.
When the private hash is about to be replaced, the per-CPU counters are
migrated to a atomic_t counter mm_struct::futex_atomic.
The migration process:
- Waiting for one RCU grace period to ensure all users observe the
current private hash. This can be skipped if a grace period elapsed
since the private hash was assigned.
- futex_private_hash::state is set to FR_ATOMIC, forcing all users to
use mm_struct::futex_atomic for reference counting.
- After a RCU grace period, all users are guaranteed to be using the
atomic counter. The per-CPU counters can now be summed up and added to
the atomic_t counter. If the resulting count is zero, the hash can be
safely replaced. Otherwise, active users still hold a valid reference.
- Once the atomic reference count drops to zero, the next futex
operation will switch to the new private hash.
call_rcu_hurry() is used to speed up transition which otherwise might be
delay with RCU_LAZY. There is nothing wrong with using call_rcu(). The
side effects would be that on auto scaling the new hash is used later
and the SET_SLOTS prctl() will block longer.
[bigeasy: commit description + mm get/ put_async]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250710110011.384614-3-bigeasy@linutronix.de
io_uring commands provide an ioctl style interface for files to
implement file specific operations. io_uring provides many features and
advanced api to commands, and it's getting hard to test as it requires
specific files/devices.
Add basic infrastucture for creating special mock files that will be
implementing the cmd api and using various io_uring features we want to
test. It'll also be useful to test some more obscure read/write/polling
edge cases in the future.
Suggested-by: chase xd <sl1589472800@gmail.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/93f21b0af58c1367a2b22635d5a7d694ad0272fc.1750599274.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Chris Mason reported a performance regression on big iron. Reports of
this kind were usually reported as part of a micro benchmark but Chris'
test did mimic his real workload. This makes it a real regression.
The root cause is rcuref_get() which is invoked during each futex
operation. If all threads of an application do this simultaneously then
it leads to cache line bouncing and the performance drops.
Disable FUTEX_PRIVATE_HASH entirely for this cycle. The performance
regression will be addressed in the following cycle enabling the option
again.
Closes: https://lore.kernel.org/all/3ad05298-351e-4d61-9972-ca45a0a50e33@meta.com/
Reported-by: Chris Mason <clm@meta.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20250630145034.8JnINEaS@linutronix.de
Most of kernel debugging facilities take a nul-terminated string for
file names for a callsite (generated from __FILE__), however the Rust
courterpart, Location, would return a Rust string (not nul-terminated)
from method .file(). And such a string cannot be passed to C debugging
function directly.
There is ongoing work to support a Location::file_with_nul() [1], which
returns a nul-terminated string from a Location. Since it's still
working in progress, and it will take some time before the feature
finally gets stabilized and the kernel's minimal rustc version might
also take a while to bump to a version that at least has that feature,
introduce a file_from_location() function, which returns a warning
string if Location::file_with_nul() is not available.
This should work in most cases because as for now the known usage of
Location::file_with_nul() is only in debugging code (e.g. might_sleep())
and there might be other information reported by the debugging code that
could help locate the problematic function, so missing the file name is
fine at the moment.
Link: https://github.com/rust-lang/rust/issues/141727 [1]
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20250619151007.61767-2-boqun.feng@gmail.com
From 077814f57f8acce13f91dc34bbd2b7e4911fbf25 Mon Sep 17 00:00:00 2001
From: Tejun Heo <tj@kernel.org>
Date: Fri, 13 Jun 2025 15:06:47 -1000
- Add CONFIG_GROUP_SCHED_BANDWIDTH which is selected by both
CONFIG_CFS_BANDWIDTH and EXT_GROUP_SCHED.
- Put bandwidth control interface files for both cgroup v1 and v2 under
CONFIG_GROUP_SCHED_BANDWIDTH.
- Update tg_bandwidth() to fetch configuration parameters from fair if
CONFIG_CFS_BANDWIDTH, SCX otherwise.
- Update tg_set_bandwidth() to update the parameters for both fair and SCX.
- Add bandwidth control parameters to struct scx_cgroup_init_args.
- Add sched_ext_ops.cgroup_set_bandwidth() which is invoked on bandwidth
control parameter updates.
- Update scx_qmap and maximal selftest to test the new feature.
Signed-off-by: Tejun Heo <tj@kernel.org>
After commit a934a57a42 ("scripts/misc-check: check missing #include
<linux/export.h> when W=1") and 7d95680d64 ("scripts/misc-check:
check unnecessary #include <linux/export.h> when W=1"), we get some build
warnings with W=1:
init/main.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
init/initramfs.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
So fix these build warnings for the init code.
Link: https://lkml.kernel.org/r/20250608141235.155206-1-chenhuacai@loongson.cn
Fixes: a934a57a42 ("scripts/misc-check: check missing #include <linux/export.h> when W=1")
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Pull Rust updates from Miguel Ojeda:
"Toolchain and infrastructure:
- KUnit '#[test]'s:
- Support KUnit-mapped 'assert!' macros.
The support that landed last cycle was very basic, and the
'assert!' macros panicked since they were the standard library
ones. Now, they are mapped to the KUnit ones in a similar way to
how is done for doctests, reusing the infrastructure there.
With this, a failing test like:
#[test]
fn my_first_test() {
assert_eq!(42, 43);
}
will report:
# my_first_test: ASSERTION FAILED at rust/kernel/lib.rs:251
Expected 42 == 43 to be true, but is false
# my_first_test.speed: normal
not ok 1 my_first_test
- Support tests with checked 'Result' return types.
The return value of test functions that return a 'Result' will
be checked, thus one can now easily catch errors when e.g. using
the '?' operator in tests.
With this, a failing test like:
#[test]
fn my_test() -> Result {
f()?;
Ok(())
}
will report:
# my_test: ASSERTION FAILED at rust/kernel/lib.rs:321
Expected is_test_result_ok(my_test()) to be true, but is false
# my_test.speed: normal
not ok 1 my_test
- Add 'kunit_tests' to the prelude.
- Clarify the remaining language unstable features in use.
- Compile 'core' with edition 2024 for Rust >= 1.87.
- Workaround 'bindgen' issue with forward references to 'enum' types.
- objtool: relax slice condition to cover more 'noreturn' functions.
- Use absolute paths in macros referencing 'core' and 'kernel'
crates.
- Skip '-mno-fdpic' flag for bindgen in GCC 32-bit arm builds.
- Clean some 'doc_markdown' lint hits -- we may enable it later on.
'kernel' crate:
- 'alloc' module:
- 'Box': support for type coercion, e.g. 'Box<T>' to 'Box<dyn U>'
if 'T' implements 'U'.
- 'Vec': implement new methods (prerequisites for nova-core and
binder): 'truncate', 'resize', 'clear', 'pop',
'push_within_capacity' (with new error type 'PushError'),
'drain_all', 'retain', 'remove' (with new error type
'RemoveError'), insert_within_capacity' (with new error type
'InsertError').
In addition, simplify 'push' using 'spare_capacity_mut', split
'set_len' into 'inc_len' and 'dec_len', add type invariant 'len
<= capacity' and simplify 'truncate' using 'dec_len'.
- 'time' module:
- Morph the Rust hrtimer subsystem into the Rust timekeeping
subsystem, covering delay, sleep, timekeeping, timers. This new
subsystem has all the relevant timekeeping C maintainers listed
in the entry.
- Replace 'Ktime' with 'Delta' and 'Instant' types to represent a
duration of time and a point in time.
- Temporarily add 'Ktime' to 'hrtimer' module to allow 'hrtimer'
to delay converting to 'Instant' and 'Delta'.
- 'xarray' module:
- Add a Rust abstraction for the 'xarray' data structure. This
abstraction allows Rust code to leverage the 'xarray' to store
types that implement 'ForeignOwnable'. This support is a
dependency for memory backing feature of the Rust null block
driver, which is waiting to be merged.
- Set up an entry in 'MAINTAINERS' for the XArray Rust support.
Patches will go to the new Rust XArray tree and then via the
Rust subsystem tree for now.
- Allow 'ForeignOwnable' to carry information about the pointed-to
type. This helps asserting alignment requirements for the
pointer passed to the foreign language.
- 'container_of!': retain pointer mut-ness and add a compile-time
check of the type of the first parameter ('$field_ptr').
- Support optional message in 'static_assert!'.
- Add C FFI types (e.g. 'c_int') to the prelude.
- 'str' module: simplify KUnit tests 'format!' macro, convert
'rusttest' tests into KUnit, take advantage of the '-> Result'
support in KUnit '#[test]'s.
- 'list' module: add examples for 'List', fix path of
'assert_pinned!' (so far unused macro rule).
- 'workqueue' module: remove 'HasWork::OFFSET'.
- 'page' module: add 'inline' attribute.
'macros' crate:
- 'module' macro: place 'cleanup_module()' in '.exit.text' section.
'pin-init' crate:
- Add 'Wrapper<T>' trait for creating pin-initializers for wrapper
structs with a structurally pinned value such as 'UnsafeCell<T>' or
'MaybeUninit<T>'.
- Add 'MaybeZeroable' derive macro to try to derive 'Zeroable', but
not error if not all fields implement it. This is needed to derive
'Zeroable' for all bindgen-generated structs.
- Add 'unsafe fn cast_[pin_]init()' functions to unsafely change the
initialized type of an initializer. These are utilized by the
'Wrapper<T>' implementations.
- Add support for visibility in 'Zeroable' derive macro.
- Add support for 'union's in 'Zeroable' derive macro.
- Upstream dev news: streamline CI, fix some bugs. Add new workflows
to check if the user-space version and the one in the kernel tree
have diverged. Use the issues tab [1] to track them, which should
help folks report and diagnose issues w.r.t. 'pin-init' better.
[1] https://github.com/rust-for-linux/pin-init/issues
Documentation:
- Testing: add docs on the new KUnit '#[test]' tests.
- Coding guidelines: explain that '///' vs. '//' applies to private
items too. Add section on C FFI types.
- Quick Start guide: update Ubuntu instructions and split them into
"25.04" and "24.04 LTS and older".
And a few other cleanups and improvements"
* tag 'rust-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (78 commits)
rust: list: Fix typo `much` in arc.rs
rust: check type of `$ptr` in `container_of!`
rust: workqueue: remove HasWork::OFFSET
rust: retain pointer mut-ness in `container_of!`
Documentation: rust: testing: add docs on the new KUnit `#[test]` tests
Documentation: rust: rename `#[test]`s to "`rusttest` host tests"
rust: str: take advantage of the `-> Result` support in KUnit `#[test]`'s
rust: str: simplify KUnit tests `format!` macro
rust: str: convert `rusttest` tests into KUnit
rust: add `kunit_tests` to the prelude
rust: kunit: support checked `-> Result`s in KUnit `#[test]`s
rust: kunit: support KUnit-mapped `assert!` macros in `#[test]`s
rust: make section names plural
rust: list: fix path of `assert_pinned!`
rust: compile libcore with edition 2024 for 1.87+
rust: dma: add missing Markdown code span
rust: task: add missing Markdown code spans and intra-doc links
rust: pci: fix docs related to missing Markdown code spans
rust: alloc: add missing Markdown code span
rust: alloc: add missing Markdown code spans
...
Pull more MM updates from Andrew Morton:
- "zram: support algorithm-specific parameters" from Sergey Senozhatsky
adds infrastructure for passing algorithm-specific parameters into
zram. A single parameter `winbits' is implemented at this time.
- "memcg: nmi-safe kmem charging" from Shakeel Butt makes memcg
charging nmi-safe, which is required by BFP, which can operate in NMI
context.
- "Some random fixes and cleanup to shmem" from Kemeng Shi implements
small fixes and cleanups in the shmem code.
- "Skip mm selftests instead when kernel features are not present" from
Zi Yan fixes some issues in the MM selftest code.
- "mm/damon: build-enable essential DAMON components by default" from
SeongJae Park reworks DAMON Kconfig to make it easier to enable
CONFIG_DAMON.
- "sched/numa: add statistics of numa balance task migration" from Libo
Chen adds more info into sysfs and procfs files to improve visibility
into the NUMA balancer's task migration activity.
- "selftests/mm: cow and gup_longterm cleanups" from Mark Brown
provides various updates to some of the MM selftests to make them
play better with the overall containing framework.
* tag 'mm-stable-2025-06-01-14-06' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (43 commits)
mm/khugepaged: clean up refcount check using folio_expected_ref_count()
selftests/mm: fix test result reporting in gup_longterm
selftests/mm: report unique test names for each cow test
selftests/mm: add helper for logging test start and results
selftests/mm: use standard ksft_finished() in cow and gup_longterm
selftests/damon/_damon_sysfs: skip testcases if CONFIG_DAMON_SYSFS is disabled
sched/numa: add statistics of numa balance task
sched/numa: fix task swap by skipping kernel threads
tools/testing: check correct variable in open_procmap()
tools/testing/vma: add missing function stub
mm/gup: update comment explaining why gup_fast() disables IRQs
selftests/mm: two fixes for the pfnmap test
mm/khugepaged: fix race with folio split/free using temporary reference
mm: add CONFIG_PAGE_BLOCK_ORDER to select page block order
mmu_notifiers: remove leftover stub macros
selftests/mm: deduplicate test names in madv_populate
kcov: rust: add flags for KCOV with Rust
mm: rust: make CONFIG_MMU ifdefs more narrow
mmu_gather: move tlb flush for VM_PFNMAP/VM_MIXEDMAP vmas into free_pgtables()
mm/damon/Kconfig: enable CONFIG_DAMON by default
...
Patch series "memcg: nmi-safe kmem charging", v4.
Users can attached their BPF programs at arbitrary execution points in the
kernel and such BPF programs may run in nmi context. In addition, these
programs can trigger memcg charged kernel allocations in the nmi context.
However memcg charging infra for kernel memory is not equipped to handle
nmi context for all architectures.
This series removes the hurdles to enable kmem charging in the nmi context
for most of the archs. For archs without CONFIG_HAVE_NMI, this series is
a noop. For archs with NMI support and have
CONFIG_ARCH_HAS_NMI_SAFE_THIS_CPU_OPS, the previous work to make memcg
stats re-entrant is sufficient for allowing kmem charging in nmi context.
For archs with NMI support but without
CONFIG_ARCH_HAS_NMI_SAFE_THIS_CPU_OPS and with ARCH_HAVE_NMI_SAFE_CMPXCHG,
this series added infra to support kmem charging in nmi context. Lastly
those archs with NMI support but without
CONFIG_ARCH_HAS_NMI_SAFE_THIS_CPU_OPS and ARCH_HAVE_NMI_SAFE_CMPXCHG, kmem
charging in nmi context is not supported at all.
Mostly used archs have support for CONFIG_ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
and this series should be almost a noop (other than making
memcg_rstat_updated nmi safe) for such archs.
This patch (of 5):
The memcg accounting and stats uses this_cpu* and atomic* ops. There are
archs which define CONFIG_HAVE_NMI but does not define
CONFIG_ARCH_HAS_NMI_SAFE_THIS_CPU_OPS and ARCH_HAVE_NMI_SAFE_CMPXCHG, so
memcg accounting for such archs in nmi context is not possible to support.
Let's just disable memcg accounting in nmi context for such archs.
Link: https://lkml.kernel.org/r/20250519063142.111219-1-shakeel.butt@linux.dev
Link: https://lkml.kernel.org/r/20250519063142.111219-2-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Pull non-MM updates from Andrew Morton:
- "hung_task: extend blocking task stacktrace dump to semaphore" from
Lance Yang enhances the hung task detector.
The detector presently dumps the blocking tasks's stack when it is
blocked on a mutex. Lance's series extends this to semaphores
- "nilfs2: improve sanity checks in dirty state propagation" from
Wentao Liang addresses a couple of minor flaws in nilfs2
- "scripts/gdb: Fixes related to lx_per_cpu()" from Illia Ostapyshyn
fixes a couple of issues in the gdb scripts
- "Support kdump with LUKS encryption by reusing LUKS volume keys" from
Coiby Xu addresses a usability problem with kdump.
When the dump device is LUKS-encrypted, the kdump kernel may not have
the keys to the encrypted filesystem. A full writeup of this is in
the series [0/N] cover letter
- "sysfs: add counters for lockups and stalls" from Max Kellermann adds
/sys/kernel/hardlockup_count and /sys/kernel/hardlockup_count and
/sys/kernel/rcu_stall_count
- "fork: Page operation cleanups in the fork code" from Pasha Tatashin
implements a number of code cleanups in fork.c
- "scripts/gdb/symbols: determine KASLR offset on s390 during early
boot" from Ilya Leoshkevich fixes some s390 issues in the gdb
scripts
* tag 'mm-nonmm-stable-2025-05-31-15-28' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (67 commits)
llist: make llist_add_batch() a static inline
delayacct: remove redundant code and adjust indentation
squashfs: add optional full compressed block caching
crash_dump, nvme: select CONFIGFS_FS as built-in
scripts/gdb/symbols: determine KASLR offset on s390 during early boot
scripts/gdb/symbols: factor out pagination_off()
scripts/gdb/symbols: factor out get_vmlinux()
kernel/panic.c: format kernel-doc comments
mailmap: update and consolidate Casey Connolly's name and email
nilfs2: remove wbc->for_reclaim handling
fork: define a local GFP_VMAP_STACK
fork: check charging success before zeroing stack
fork: clean-up naming of vm_stack/vm_struct variables in vmap stacks code
fork: clean-up ifdef logic around stack allocation
kernel/rcu/tree_stall: add /sys/kernel/rcu_stall_count
kernel/watchdog: add /sys/kernel/{hard,soft}lockup_count
x86/crash: make the page that stores the dm crypt keys inaccessible
x86/crash: pass dm crypt keys to kdump kernel
Revert "x86/mm: Remove unused __set_memory_prot()"
crash_dump: retrieve dm crypt keys in kdump kernel
...
