mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/
synced 2025-04-20 05:08:28 +09:00
741 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Oleg Nesterov
|
9133607de3
|
exit: fix the usage of delay_group_leader->exit_code in do_notify_parent() and pidfs_exit()
Consider a process with a group leader L and a sub-thread T. L does sys_exit(1), then T does sys_exit_group(2). In this case wait_task_zombie(L) will notice SIGNAL_GROUP_EXIT and use L->signal->group_exit_code, this is correct. But, before that, do_notify_parent(L) called by release_task(T) will use L->exit_code != L->signal->group_exit_code, and this is not consistent. We don't really care, I think that nobody relies on the info which comes with SIGCHLD, if nothing else SIGCHLD < SIGRTMIN can be queued only once. But pidfs_exit() is more problematic, I think pidfs_exit_info->exit_code should report ->group_exit_code in this case, just like wait_task_zombie(). TODO: with this change we can hopefully cleanup (or may be even kill) the similar SIGNAL_GROUP_EXIT checks, at least in wait_task_zombie(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20250324171941.GA13114@redhat.com Signed-off-by: Christian Brauner <brauner@kernel.org> |
||
|
Oleg Nesterov
|
0b7747a547
|
pidfs: cleanup the usage of do_notify_pidfd()
If a single-threaded process exits do_notify_pidfd() will be called twice, from exit_notify() and right after that from do_notify_parent(). 1. Change exit_notify() to call do_notify_pidfd() if the exiting task is not ptraced and it is not a group leader. 2. Change do_notify_parent() to call do_notify_pidfd() unconditionally. If tsk is not ptraced, do_notify_parent() will only be called when it is a group-leader and thread_group_empty() is true. This means that if tsk is ptraced, do_notify_pidfd() will be called from do_notify_parent() even if tsk is a delay_group_leader(). But this case is less common, and apart from the unnecessary __wake_up() is harmless. Granted, this unnecessary __wake_up() can be avoided, but I don't want to do it in this patch because it's just a consequence of another historical oddity: we notify the tracer even if !thread_group_empty(), but do_wait() from debugger can't work until all other threads exit. With or without this patch we should either eliminate do_notify_parent() in this case, or change do_wait(WEXITED) to untrace the ptraced delay_group_leader() at least when ptrace_reparented(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20250323171955.GA834@redhat.com Signed-off-by: Christian Brauner <brauner@kernel.org> |
||
|
Linus Torvalds
|
b0cb56cbbd |
kernel-6.15-rc1.tasklist_lock
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCZ90q3QAKCRCRxhvAZXjc
oh2TAP9vrH7ft0TpJN2RyFNels/QaYmoiuw4TdVZhbEzvCUyYgEA1Bnx+OGmkdbT
e4W3NkWJpn8BBjHfz3z3P7SImDdcCAw=
=a6/i
-----END PGP SIGNATURE-----
Merge tag 'kernel-6.15-rc1.tasklist_lock' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull tasklist_lock optimizations from Christian Brauner:
"According to the performance testbots this brings a 23% performance
increase when creating new processes:
- Reduce tasklist_lock hold time on exit:
- Perform add_device_randomness() without tasklist_lock
- Perform free_pid() calls outside of tasklist_lock
- Drop irq disablement around pidmap_lock
- Add some tasklist_lock asserts
- Call flush_sigqueue() lockless by changing release_task()
- Don't pointlessly clear TIF_SIGPENDING in __exit_signal() ->
clear_tsk_thread_flag()"
* tag 'kernel-6.15-rc1.tasklist_lock' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
pid: drop irq disablement around pidmap_lock
pid: perform free_pid() calls outside of tasklist_lock
pid: sprinkle tasklist_lock asserts
exit: hoist get_pid() in release_task() outside of tasklist_lock
exit: perform add_device_randomness() without tasklist_lock
exit: kill the pointless __exit_signal()->clear_tsk_thread_flag(TIF_SIGPENDING)
exit: change the release_task() paths to call flush_sigqueue() lockless
|
||
|
Christian Brauner
|
0fb482728b
|
pidfs: improve multi-threaded exec and premature thread-group leader exit polling
This is another attempt trying to make pidfd polling for multi-threaded
exec and premature thread-group leader exit consistent.
A quick recap of these two cases:
(1) During a multi-threaded exec by a subthread, i.e., non-thread-group
leader thread, all other threads in the thread-group including the
thread-group leader are killed and the struct pid of the
thread-group leader will be taken over by the subthread that called
exec. IOW, two tasks change their TIDs.
(2) A premature thread-group leader exit means that the thread-group
leader exited before all of the other subthreads in the thread-group
have exited.
Both cases lead to inconsistencies for pidfd polling with PIDFD_THREAD.
Any caller that holds a PIDFD_THREAD pidfd to the current thread-group
leader may or may not see an exit notification on the file descriptor
depending on when poll is performed. If the poll is performed before the
exec of the subthread has concluded an exit notification is generated
for the old thread-group leader. If the poll is performed after the exec
of the subthread has concluded no exit notification is generated for the
old thread-group leader.
The correct behavior would be to simply not generate an exit
notification on the struct pid of a subhthread exec because the struct
pid is taken over by the subthread and thus remains alive.
But this is difficult to handle because a thread-group may exit
prematurely as mentioned in (2). In that case an exit notification is
reliably generated but the subthreads may continue to run for an
indeterminate amount of time and thus also may exec at some point.
So far there was no way to distinguish between (1) and (2) internally.
This tiny series tries to address this problem by discarding
PIDFD_THREAD notification on premature thread-group leader exit.
If that works correctly then no exit notifications are generated for a
PIDFD_THREAD pidfd for a thread-group leader until all subthreads have
been reaped. If a subthread should exec aftewards no exit notification
will be generated until that task exits or it creates subthreads and
repeates the cycle.
Co-Developed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20250320-work-pidfs-thread_group-v4-1-da678ce805bf@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
||
|
Christian Brauner
|
4513522984
|
pidfs: record exit code and cgroupid at exit
Record the exit code and cgroupid in release_task() and stash in struct pidfs_exit_info so it can be retrieved even after the task has been reaped. Link: https://lore.kernel.org/r/20250305-work-pidfs-kill_on_last_close-v3-5-c8c3d8361705@kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Christian Brauner <brauner@kernel.org> |
||
|
Mateusz Guzik
|
7903f907a2
|
pid: perform free_pid() calls outside of tasklist_lock
As the clone side already executes pid allocation with only pidmap_lock held, issuing free_pid() while still holding tasklist_lock exacerbates total hold time of the latter. More things may show up later which require initial clean up with the lock held and allow finishing without it. For that reason a struct to collect such work is added instead of merely passing the pid array. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Mateusz Guzik <mjguzik@gmail.com> Link: https://lore.kernel.org/r/20250206164415.450051-5-mjguzik@gmail.com Acked-by: "Liam R. Howlett" <Liam.Howlett@Oracle.com> Signed-off-by: Christian Brauner <brauner@kernel.org> |
||
|
Mateusz Guzik
|
6731cd97e6
|
exit: hoist get_pid() in release_task() outside of tasklist_lock
Reduces hold time as get_pid() contains an atomic. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Mateusz Guzik <mjguzik@gmail.com> Link: https://lore.kernel.org/r/20250206164415.450051-3-mjguzik@gmail.com Acked-by: "Liam R. Howlett" <Liam.Howlett@Oracle.com> Signed-off-by: Christian Brauner <brauner@kernel.org> |
||
|
Mateusz Guzik
|
1ab2785694
|
exit: perform add_device_randomness() without tasklist_lock
Parallel calls to add_device_randomness() contend on their own. The clone side aleady runs outside of tasklist_lock, which in turn means any caller on the exit side extends the tasklist_lock hold time while contending on the random-private lock. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Mateusz Guzik <mjguzik@gmail.com> Link: https://lore.kernel.org/r/20250206164415.450051-2-mjguzik@gmail.com Acked-by: "Liam R. Howlett" <Liam.Howlett@Oracle.com> Signed-off-by: Christian Brauner <brauner@kernel.org> |
||
|
Oleg Nesterov
|
43966114b4
|
exit: kill the pointless __exit_signal()->clear_tsk_thread_flag(TIF_SIGPENDING)
It predates the git history and most probably it was never needed. It doesn't really hurt, but it looks confusing because its purpose is not clear at all. release_task(p) is called when this task has already passed exit_notify() so signal_pending(p) == T shouldn't make any difference. And even _if_ there were a subtle reason to clear TIF_SIGPENDING after exit_notify(), this clear_tsk_thread_flag() can't help anyway. If the exiting task is a group leader or if it is ptraced, release_task() will be likely called when this task has already done its last schedule() from do_task_dead(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20250206152334.GB14620@redhat.com Acked-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org> |
||
|
Oleg Nesterov
|
fb3bbcfe34
|
exit: change the release_task() paths to call flush_sigqueue() lockless
A task can block a signal, accumulate up to RLIMIT_SIGPENDING sigqueues, and exit. In this case __exit_signal()->flush_sigqueue() called with irqs disabled can trigger a hard lockup, see https://lore.kernel.org/all/20190322114917.GC28876@redhat.com/ Fortunately, after the recent posixtimer changes sys_timer_delete() paths no longer try to clear SIGQUEUE_PREALLOC and/or free tmr->sigq, and after the exiting task passes __exit_signal() lock_task_sighand() can't succeed and pid_task(tmr->it_pid) will return NULL. This means that after __exit_signal(tsk) nobody can play with tsk->pending or (if group_dead) with tsk->signal->shared_pending, so release_task() can safely call flush_sigqueue() after write_unlock_irq(&tasklist_lock). TODO: - we can probably shift posix_cpu_timers_exit() as well - do_sigaction() can hit the similar problem Signed-off-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20250206152314.GA14620@redhat.com Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org> |
||
|
Joel Granados
|
1751f872cc |
treewide: const qualify ctl_tables where applicable
Add the const qualifier to all the ctl_tables in the tree except for
watchdog_hardlockup_sysctl, memory_allocation_profiling_sysctls,
loadpin_sysctl_table and the ones calling register_net_sysctl (./net,
drivers/inifiniband dirs). These are special cases as they use a
registration function with a non-const qualified ctl_table argument or
modify the arrays before passing them on to the registration function.
Constifying ctl_table structs will prevent the modification of
proc_handler function pointers as the arrays would reside in .rodata.
This is made possible after commit 78eb4ea25cd5 ("sysctl: treewide:
constify the ctl_table argument of proc_handlers") constified all the
proc_handlers.
Created this by running an spatch followed by a sed command:
Spatch:
virtual patch
@
depends on !(file in "net")
disable optional_qualifier
@
identifier table_name != {
watchdog_hardlockup_sysctl,
iwcm_ctl_table,
ucma_ctl_table,
memory_allocation_profiling_sysctls,
loadpin_sysctl_table
};
@@
+ const
struct ctl_table table_name [] = { ... };
sed:
sed --in-place \
-e "s/struct ctl_table .table = &uts_kern/const struct ctl_table *table = \&uts_kern/" \
kernel/utsname_sysctl.c
Reviewed-by: Song Liu <song@kernel.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> # for kernel/trace/
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> # SCSI
Reviewed-by: Darrick J. Wong <djwong@kernel.org> # xfs
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Corey Minyard <cminyard@mvista.com>
Acked-by: Wei Liu <wei.liu@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Bill O'Donnell <bodonnel@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Acked-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Acked-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Joel Granados <joel.granados@kernel.org>
|
||
|
Al Viro
|
be5498cac2 |
remove pointless includes of <linux/fdtable.h>
some of those used to be needed, some had been cargo-culted for no reason... Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> |
||
|
Linus Torvalds
|
617a814f14 |
ALong with the usual shower of singleton patches, notable patch series in
this pull request are:
"Align kvrealloc() with krealloc()" from Danilo Krummrich. Adds
consistency to the APIs and behaviour of these two core allocation
functions. This also simplifies/enables Rustification.
"Some cleanups for shmem" from Baolin Wang. No functional changes - mode
code reuse, better function naming, logic simplifications.
"mm: some small page fault cleanups" from Josef Bacik. No functional
changes - code cleanups only.
"Various memory tiering fixes" from Zi Yan. A small fix and a little
cleanup.
"mm/swap: remove boilerplate" from Yu Zhao. Code cleanups and
simplifications and .text shrinkage.
"Kernel stack usage histogram" from Pasha Tatashin and Shakeel Butt. This
is a feature, it adds new feilds to /proc/vmstat such as
$ grep kstack /proc/vmstat
kstack_1k 3
kstack_2k 188
kstack_4k 11391
kstack_8k 243
kstack_16k 0
which tells us that 11391 processes used 4k of stack while none at all
used 16k. Useful for some system tuning things, but partivularly useful
for "the dynamic kernel stack project".
"kmemleak: support for percpu memory leak detect" from Pavel Tikhomirov.
Teaches kmemleak to detect leaksage of percpu memory.
"mm: memcg: page counters optimizations" from Roman Gushchin. "3
independent small optimizations of page counters".
"mm: split PTE/PMD PT table Kconfig cleanups+clarifications" from David
Hildenbrand. Improves PTE/PMD splitlock detection, makes powerpc/8xx work
correctly by design rather than by accident.
"mm: remove arch_make_page_accessible()" from David Hildenbrand. Some
folio conversions which make arch_make_page_accessible() unneeded.
"mm, memcg: cg2 memory{.swap,}.peak write handlers" fro David Finkel.
Cleans up and fixes our handling of the resetting of the cgroup/process
peak-memory-use detector.
"Make core VMA operations internal and testable" from Lorenzo Stoakes.
Rationalizaion and encapsulation of the VMA manipulation APIs. With a
view to better enable testing of the VMA functions, even from a
userspace-only harness.
"mm: zswap: fixes for global shrinker" from Takero Funaki. Fix issues in
the zswap global shrinker, resulting in improved performance.
"mm: print the promo watermark in zoneinfo" from Kaiyang Zhao. Fill in
some missing info in /proc/zoneinfo.
"mm: replace follow_page() by folio_walk" from David Hildenbrand. Code
cleanups and rationalizations (conversion to folio_walk()) resulting in
the removal of follow_page().
"improving dynamic zswap shrinker protection scheme" from Nhat Pham. Some
tuning to improve zswap's dynamic shrinker. Significant reductions in
swapin and improvements in performance are shown.
"mm: Fix several issues with unaccepted memory" from Kirill Shutemov.
Improvements to the new unaccepted memory feature,
"mm/mprotect: Fix dax puds" from Peter Xu. Implements mprotect on DAX
PUDs. This was missing, although nobody seems to have notied yet.
"Introduce a store type enum for the Maple tree" from Sidhartha Kumar.
Cleanups and modest performance improvements for the maple tree library
code.
"memcg: further decouple v1 code from v2" from Shakeel Butt. Move more
cgroup v1 remnants away from the v2 memcg code.
"memcg: initiate deprecation of v1 features" from Shakeel Butt. Adds
various warnings telling users that memcg v1 features are deprecated.
"mm: swap: mTHP swap allocator base on swap cluster order" from Chris Li.
Greatly improves the success rate of the mTHP swap allocation.
"mm: introduce numa_memblks" from Mike Rapoport. Moves various disparate
per-arch implementations of numa_memblk code into generic code.
"mm: batch free swaps for zap_pte_range()" from Barry Song. Greatly
improves the performance of munmap() of swap-filled ptes.
"support large folio swap-out and swap-in for shmem" from Baolin Wang.
With this series we no longer split shmem large folios into simgle-page
folios when swapping out shmem.
"mm/hugetlb: alloc/free gigantic folios" from Yu Zhao. Nice performance
improvements and code reductions for gigantic folios.
"support shmem mTHP collapse" from Baolin Wang. Adds support for
khugepaged's collapsing of shmem mTHP folios.
"mm: Optimize mseal checks" from Pedro Falcato. Fixes an mprotect()
performance regression due to the addition of mseal().
"Increase the number of bits available in page_type" from Matthew Wilcox.
Increases the number of bits available in page_type!
"Simplify the page flags a little" from Matthew Wilcox. Many legacy page
flags are now folio flags, so the page-based flags and their
accessors/mutators can be removed.
"mm: store zero pages to be swapped out in a bitmap" from Usama Arif. An
optimization which permits us to avoid writing/reading zero-filled zswap
pages to backing store.
"Avoid MAP_FIXED gap exposure" from Liam Howlett. Fixes a race window
which occurs when a MAP_FIXED operqtion is occurring during an unrelated
vma tree walk.
"mm: remove vma_merge()" from Lorenzo Stoakes. Major rotorooting of the
vma_merge() functionality, making ot cleaner, more testable and better
tested.
"misc fixups for DAMON {self,kunit} tests" from SeongJae Park. Minor
fixups of DAMON selftests and kunit tests.
"mm: memory_hotplug: improve do_migrate_range()" from Kefeng Wang. Code
cleanups and folio conversions.
"Shmem mTHP controls and stats improvements" from Ryan Roberts. Cleanups
for shmem controls and stats.
"mm: count the number of anonymous THPs per size" from Barry Song. Expose
additional anon THP stats to userspace for improved tuning.
"mm: finish isolate/putback_lru_page()" from Kefeng Wang: more folio
conversions and removal of now-unused page-based APIs.
"replace per-quota region priorities histogram buffer with per-context
one" from SeongJae Park. DAMON histogram rationalization.
"Docs/damon: update GitHub repo URLs and maintainer-profile" from SeongJae
Park. DAMON documentation updates.
"mm/vdpa: correct misuse of non-direct-reclaim __GFP_NOFAIL and improve
related doc and warn" from Jason Wang: fixes usage of page allocator
__GFP_NOFAIL and GFP_ATOMIC flags.
"mm: split underused THPs" from Yu Zhao. Improve THP=always policy - this
was overprovisioning THPs in sparsely accessed memory areas.
"zram: introduce custom comp backends API" frm Sergey Senozhatsky. Add
support for zram run-time compression algorithm tuning.
"mm: Care about shadow stack guard gap when getting an unmapped area" from
Mark Brown. Fix up the various arch_get_unmapped_area() implementations
to better respect guard areas.
"Improve mem_cgroup_iter()" from Kinsey Ho. Improve the reliability of
mem_cgroup_iter() and various code cleanups.
"mm: Support huge pfnmaps" from Peter Xu. Extends the usage of huge
pfnmap support.
"resource: Fix region_intersects() vs add_memory_driver_managed()" from
Huang Ying. Fix a bug in region_intersects() for systems with CXL memory.
"mm: hwpoison: two more poison recovery" from Kefeng Wang. Teaches a
couple more code paths to correctly recover from the encountering of
poisoned memry.
"mm: enable large folios swap-in support" from Barry Song. Support the
swapin of mTHP memory into appropriately-sized folios, rather than into
single-page folios.
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCZu1BBwAKCRDdBJ7gKXxA
jlWNAQDYlqQLun7bgsAN4sSvi27VUuWv1q70jlMXTfmjJAvQqwD/fBFVR6IOOiw7
AkDbKWP2k0hWPiNJBGwoqxdHHx09Xgo=
=s0T+
-----END PGP SIGNATURE-----
Merge tag 'mm-stable-2024-09-20-02-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
"Along with the usual shower of singleton patches, notable patch series
in this pull request are:
- "Align kvrealloc() with krealloc()" from Danilo Krummrich. Adds
consistency to the APIs and behaviour of these two core allocation
functions. This also simplifies/enables Rustification.
- "Some cleanups for shmem" from Baolin Wang. No functional changes -
mode code reuse, better function naming, logic simplifications.
- "mm: some small page fault cleanups" from Josef Bacik. No
functional changes - code cleanups only.
- "Various memory tiering fixes" from Zi Yan. A small fix and a
little cleanup.
- "mm/swap: remove boilerplate" from Yu Zhao. Code cleanups and
simplifications and .text shrinkage.
- "Kernel stack usage histogram" from Pasha Tatashin and Shakeel
Butt. This is a feature, it adds new feilds to /proc/vmstat such as
$ grep kstack /proc/vmstat
kstack_1k 3
kstack_2k 188
kstack_4k 11391
kstack_8k 243
kstack_16k 0
which tells us that 11391 processes used 4k of stack while none at
all used 16k. Useful for some system tuning things, but
partivularly useful for "the dynamic kernel stack project".
- "kmemleak: support for percpu memory leak detect" from Pavel
Tikhomirov. Teaches kmemleak to detect leaksage of percpu memory.
- "mm: memcg: page counters optimizations" from Roman Gushchin. "3
independent small optimizations of page counters".
- "mm: split PTE/PMD PT table Kconfig cleanups+clarifications" from
David Hildenbrand. Improves PTE/PMD splitlock detection, makes
powerpc/8xx work correctly by design rather than by accident.
- "mm: remove arch_make_page_accessible()" from David Hildenbrand.
Some folio conversions which make arch_make_page_accessible()
unneeded.
- "mm, memcg: cg2 memory{.swap,}.peak write handlers" fro David
Finkel. Cleans up and fixes our handling of the resetting of the
cgroup/process peak-memory-use detector.
- "Make core VMA operations internal and testable" from Lorenzo
Stoakes. Rationalizaion and encapsulation of the VMA manipulation
APIs. With a view to better enable testing of the VMA functions,
even from a userspace-only harness.
- "mm: zswap: fixes for global shrinker" from Takero Funaki. Fix
issues in the zswap global shrinker, resulting in improved
performance.
- "mm: print the promo watermark in zoneinfo" from Kaiyang Zhao. Fill
in some missing info in /proc/zoneinfo.
- "mm: replace follow_page() by folio_walk" from David Hildenbrand.
Code cleanups and rationalizations (conversion to folio_walk())
resulting in the removal of follow_page().
- "improving dynamic zswap shrinker protection scheme" from Nhat
Pham. Some tuning to improve zswap's dynamic shrinker. Significant
reductions in swapin and improvements in performance are shown.
- "mm: Fix several issues with unaccepted memory" from Kirill
Shutemov. Improvements to the new unaccepted memory feature,
- "mm/mprotect: Fix dax puds" from Peter Xu. Implements mprotect on
DAX PUDs. This was missing, although nobody seems to have notied
yet.
- "Introduce a store type enum for the Maple tree" from Sidhartha
Kumar. Cleanups and modest performance improvements for the maple
tree library code.
- "memcg: further decouple v1 code from v2" from Shakeel Butt. Move
more cgroup v1 remnants away from the v2 memcg code.
- "memcg: initiate deprecation of v1 features" from Shakeel Butt.
Adds various warnings telling users that memcg v1 features are
deprecated.
- "mm: swap: mTHP swap allocator base on swap cluster order" from
Chris Li. Greatly improves the success rate of the mTHP swap
allocation.
- "mm: introduce numa_memblks" from Mike Rapoport. Moves various
disparate per-arch implementations of numa_memblk code into generic
code.
- "mm: batch free swaps for zap_pte_range()" from Barry Song. Greatly
improves the performance of munmap() of swap-filled ptes.
- "support large folio swap-out and swap-in for shmem" from Baolin
Wang. With this series we no longer split shmem large folios into
simgle-page folios when swapping out shmem.
- "mm/hugetlb: alloc/free gigantic folios" from Yu Zhao. Nice
performance improvements and code reductions for gigantic folios.
- "support shmem mTHP collapse" from Baolin Wang. Adds support for
khugepaged's collapsing of shmem mTHP folios.
- "mm: Optimize mseal checks" from Pedro Falcato. Fixes an mprotect()
performance regression due to the addition of mseal().
- "Increase the number of bits available in page_type" from Matthew
Wilcox. Increases the number of bits available in page_type!
- "Simplify the page flags a little" from Matthew Wilcox. Many legacy
page flags are now folio flags, so the page-based flags and their
accessors/mutators can be removed.
- "mm: store zero pages to be swapped out in a bitmap" from Usama
Arif. An optimization which permits us to avoid writing/reading
zero-filled zswap pages to backing store.
- "Avoid MAP_FIXED gap exposure" from Liam Howlett. Fixes a race
window which occurs when a MAP_FIXED operqtion is occurring during
an unrelated vma tree walk.
- "mm: remove vma_merge()" from Lorenzo Stoakes. Major rotorooting of
the vma_merge() functionality, making ot cleaner, more testable and
better tested.
- "misc fixups for DAMON {self,kunit} tests" from SeongJae Park.
Minor fixups of DAMON selftests and kunit tests.
- "mm: memory_hotplug: improve do_migrate_range()" from Kefeng Wang.
Code cleanups and folio conversions.
- "Shmem mTHP controls and stats improvements" from Ryan Roberts.
Cleanups for shmem controls and stats.
- "mm: count the number of anonymous THPs per size" from Barry Song.
Expose additional anon THP stats to userspace for improved tuning.
- "mm: finish isolate/putback_lru_page()" from Kefeng Wang: more
folio conversions and removal of now-unused page-based APIs.
- "replace per-quota region priorities histogram buffer with
per-context one" from SeongJae Park. DAMON histogram
rationalization.
- "Docs/damon: update GitHub repo URLs and maintainer-profile" from
SeongJae Park. DAMON documentation updates.
- "mm/vdpa: correct misuse of non-direct-reclaim __GFP_NOFAIL and
improve related doc and warn" from Jason Wang: fixes usage of page
allocator __GFP_NOFAIL and GFP_ATOMIC flags.
- "mm: split underused THPs" from Yu Zhao. Improve THP=always policy.
This was overprovisioning THPs in sparsely accessed memory areas.
- "zram: introduce custom comp backends API" frm Sergey Senozhatsky.
Add support for zram run-time compression algorithm tuning.
- "mm: Care about shadow stack guard gap when getting an unmapped
area" from Mark Brown. Fix up the various arch_get_unmapped_area()
implementations to better respect guard areas.
- "Improve mem_cgroup_iter()" from Kinsey Ho. Improve the reliability
of mem_cgroup_iter() and various code cleanups.
- "mm: Support huge pfnmaps" from Peter Xu. Extends the usage of huge
pfnmap support.
- "resource: Fix region_intersects() vs add_memory_driver_managed()"
from Huang Ying. Fix a bug in region_intersects() for systems with
CXL memory.
- "mm: hwpoison: two more poison recovery" from Kefeng Wang. Teaches
a couple more code paths to correctly recover from the encountering
of poisoned memry.
- "mm: enable large folios swap-in support" from Barry Song. Support
the swapin of mTHP memory into appropriately-sized folios, rather
than into single-page folios"
* tag 'mm-stable-2024-09-20-02-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (416 commits)
zram: free secondary algorithms names
uprobes: turn xol_area->pages[2] into xol_area->page
uprobes: introduce the global struct vm_special_mapping xol_mapping
Revert "uprobes: use vm_special_mapping close() functionality"
mm: support large folios swap-in for sync io devices
mm: add nr argument in mem_cgroup_swapin_uncharge_swap() helper to support large folios
mm: fix swap_read_folio_zeromap() for large folios with partial zeromap
mm/debug_vm_pgtable: Use pxdp_get() for accessing page table entries
set_memory: add __must_check to generic stubs
mm/vma: return the exact errno in vms_gather_munmap_vmas()
memcg: cleanup with !CONFIG_MEMCG_V1
mm/show_mem.c: report alloc tags in human readable units
mm: support poison recovery from copy_present_page()
mm: support poison recovery from do_cow_fault()
resource, kunit: add test case for region_intersects()
resource: make alloc_free_mem_region() works for iomem_resource
mm: z3fold: deprecate CONFIG_Z3FOLD
vfio/pci: implement huge_fault support
mm/arm64: support large pfn mappings
mm/x86: support large pfn mappings
...
|
||
|
Pasha Tatashin
|
fbe76a6557 |
task_stack: uninline stack_not_used
Given that stack_not_used() is not performance critical function uninline it. Link: https://lkml.kernel.org/r/20240730150158.832783-4-pasha.tatashin@soleen.com Link: https://lkml.kernel.org/r/20240724203322.2765486-4-pasha.tatashin@soleen.com Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com> Cc: Kent Overstreet <kent.overstreet@linux.dev> Cc: Li Zhijian <lizhijian@fujitsu.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
Pasha Tatashin
|
c4a6fce856 |
vmstat: kernel stack usage histogram
As part of the dynamic kernel stack project, we need to know the amount of data that can be saved by reducing the default kernel stack size [1]. Provide a kernel stack usage histogram to aid in optimizing kernel stack sizes and minimizing memory waste in large-scale environments. The histogram divides stack usage into power-of-two buckets and reports the results in /proc/vmstat. This information is especially valuable in environments with millions of machines, where even small optimizations can have a significant impact. The histogram data is presented in /proc/vmstat with entries like "kstack_1k", "kstack_2k", and so on, indicating the number of threads that exited with stack usage falling within each respective bucket. Example outputs: Intel: $ grep kstack /proc/vmstat kstack_1k 3 kstack_2k 188 kstack_4k 11391 kstack_8k 243 kstack_16k 0 ARM with 64K page_size: $ grep kstack /proc/vmstat kstack_1k 1 kstack_2k 340 kstack_4k 25212 kstack_8k 1659 kstack_16k 0 kstack_32k 0 kstack_64k 0 Note: once the dynamic kernel stack is implemented it will depend on the implementation the usability of this feature: On hardware that supports faults on kernel stacks, we will have other metrics that show the total number of pages allocated for stacks. On hardware where faults are not supported, we will most likely have some optimization where only some threads are extended, and for those, these metrics will still be very useful. [1] https://lwn.net/Articles/974367 Link: https://lkml.kernel.org/r/20240730150158.832783-3-pasha.tatashin@soleen.com Link: https://lkml.kernel.org/r/20240724203322.2765486-3-pasha.tatashin@soleen.com Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com> Reviewed-by: Kent Overstreet <kent.overstreet@linux.dev> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com> Cc: Li Zhijian <lizhijian@fujitsu.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
Paul E. McKenney
|
b8e753128e |
exit: Sleep at TASK_IDLE when waiting for application core dump
Currently, the coredump_task_exit() function sets the task state to TASK_UNINTERRUPTIBLE|TASK_FREEZABLE, which usually works well. But a combination of large memory and slow (and/or highly contended) mass storage can cause application core dumps to take more than two minutes, which can cause check_hung_task(), which is invoked by check_hung_uninterruptible_tasks(), to produce task-blocked splats. There does not seem to be any reasonable benefit to getting these splats. Furthermore, as Oleg Nesterov points out, TASK_UNINTERRUPTIBLE could be misleading because the task sleeping in coredump_task_exit() really is killable, albeit indirectly. See the check of signal->core_state in prepare_signal() and the check of fatal_signal_pending() in dump_interrupted(), which bypass the normal unkillability of TASK_UNINTERRUPTIBLE, resulting in coredump_finish() invoking wake_up_process() on any threads sleeping in coredump_task_exit(). Therefore, change that TASK_UNINTERRUPTIBLE to TASK_IDLE. Reported-by: Anhad Jai Singh <ffledgling@meta.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Christian Brauner <brauner@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Chris Mason <clm@fb.com> Cc: Rik van Riel <riel@surriel.com> |
||
|
Linus Torvalds
|
fbc90c042c |
- 875fa64577da ("mm/hugetlb_vmemmap: fix race with speculative PFN
walkers") is known to cause a performance regression
(https://lore.kernel.org/all/3acefad9-96e5-4681-8014-827d6be71c7a@linux.ibm.com/T/#mfa809800a7862fb5bdf834c6f71a3a5113eb83ff).
Yu has a fix which I'll send along later via the hotfixes branch.
- In the series "mm: Avoid possible overflows in dirty throttling" Jan
Kara addresses a couple of issues in the writeback throttling code.
These fixes are also targetted at -stable kernels.
- Ryusuke Konishi's series "nilfs2: fix potential issues related to
reserved inodes" does that. This should actually be in the
mm-nonmm-stable tree, along with the many other nilfs2 patches. My bad.
- More folio conversions from Kefeng Wang in the series "mm: convert to
folio_alloc_mpol()"
- Kemeng Shi has sent some cleanups to the writeback code in the series
"Add helper functions to remove repeated code and improve readability of
cgroup writeback"
- Kairui Song has made the swap code a little smaller and a little
faster in the series "mm/swap: clean up and optimize swap cache index".
- In the series "mm/memory: cleanly support zeropage in
vm_insert_page*(), vm_map_pages*() and vmf_insert_mixed()" David
Hildenbrand has reworked the rather sketchy handling of the use of the
zeropage in MAP_SHARED mappings. I don't see any runtime effects here -
more a cleanup/understandability/maintainablity thing.
- Dev Jain has improved selftests/mm/va_high_addr_switch.c's handling of
higher addresses, for aarch64. The (poorly named) series is
"Restructure va_high_addr_switch".
- The core TLB handling code gets some cleanups and possible slight
optimizations in Bang Li's series "Add update_mmu_tlb_range() to
simplify code".
- Jane Chu has improved the handling of our
fake-an-unrecoverable-memory-error testing feature MADV_HWPOISON in the
series "Enhance soft hwpoison handling and injection".
- Jeff Johnson has sent a billion patches everywhere to add
MODULE_DESCRIPTION() to everything. Some landed in this pull.
- In the series "mm: cleanup MIGRATE_SYNC_NO_COPY mode", Kefeng Wang has
simplified migration's use of hardware-offload memory copying.
- Yosry Ahmed performs more folio API conversions in his series "mm:
zswap: trivial folio conversions".
- In the series "large folios swap-in: handle refault cases first",
Chuanhua Han inches us forward in the handling of large pages in the
swap code. This is a cleanup and optimization, working toward the end
objective of full support of large folio swapin/out.
- In the series "mm,swap: cleanup VMA based swap readahead window
calculation", Huang Ying has contributed some cleanups and a possible
fixlet to his VMA based swap readahead code.
- In the series "add mTHP support for anonymous shmem" Baolin Wang has
taught anonymous shmem mappings to use multisize THP. By default this
is a no-op - users must opt in vis sysfs controls. Dramatic
improvements in pagefault latency are realized.
- David Hildenbrand has some cleanups to our remaining use of
page_mapcount() in the series "fs/proc: move page_mapcount() to
fs/proc/internal.h".
- David also has some highmem accounting cleanups in the series
"mm/highmem: don't track highmem pages manually".
- Build-time fixes and cleanups from John Hubbard in the series
"cleanups, fixes, and progress towards avoiding "make headers"".
- Cleanups and consolidation of the core pagemap handling from Barry
Song in the series "mm: introduce pmd|pte_needs_soft_dirty_wp helpers
and utilize them".
- Lance Yang's series "Reclaim lazyfree THP without splitting" has
reduced the latency of the reclaim of pmd-mapped THPs under fairly
common circumstances. A 10x speedup is seen in a microbenchmark.
It does this by punting to aother CPU but I guess that's a win unless
all CPUs are pegged.
- hugetlb_cgroup cleanups from Xiu Jianfeng in the series
"mm/hugetlb_cgroup: rework on cftypes".
- Miaohe Lin's series "Some cleanups for memory-failure" does just that
thing.
- Is anyone reading this stuff? If so, email me!
- Someone other than SeongJae has developed a DAMON feature in Honggyu
Kim's series "DAMON based tiered memory management for CXL memory".
This adds DAMON features which may be used to help determine the
efficiency of our placement of CXL/PCIe attached DRAM.
- DAMON user API centralization and simplificatio work in SeongJae
Park's series "mm/damon: introduce DAMON parameters online commit
function".
- In the series "mm: page_type, zsmalloc and page_mapcount_reset()"
David Hildenbrand does some maintenance work on zsmalloc - partially
modernizing its use of pageframe fields.
- Kefeng Wang provides more folio conversions in the series "mm: remove
page_maybe_dma_pinned() and page_mkclean()".
- More cleanup from David Hildenbrand, this time in the series
"mm/memory_hotplug: use PageOffline() instead of PageReserved() for
!ZONE_DEVICE". It "enlightens memory hotplug more about PageOffline()
pages" and permits the removal of some virtio-mem hacks.
- Barry Song's series "mm: clarify folio_add_new_anon_rmap() and
__folio_add_anon_rmap()" is a cleanup to the anon folio handling in
preparation for mTHP (multisize THP) swapin.
- Kefeng Wang's series "mm: improve clear and copy user folio"
implements more folio conversions, this time in the area of large folio
userspace copying.
- The series "Docs/mm/damon/maintaier-profile: document a mailing tool
and community meetup series" tells people how to get better involved
with other DAMON developers. From SeongJae Park.
- A large series ("kmsan: Enable on s390") from Ilya Leoshkevich does
that.
- David Hildenbrand sends along more cleanups, this time against the
migration code. The series is "mm/migrate: move NUMA hinting fault
folio isolation + checks under PTL".
- Jan Kara has found quite a lot of strangenesses and minor errors in
the readahead code. He addresses this in the series "mm: Fix various
readahead quirks".
- SeongJae Park's series "selftests/damon: test DAMOS tried regions and
{min,max}_nr_regions" adds features and addresses errors in DAMON's self
testing code.
- Gavin Shan has found a userspace-triggerable WARN in the pagecache
code. The series "mm/filemap: Limit page cache size to that supported
by xarray" addresses this. The series is marked cc:stable.
- Chengming Zhou's series "mm/ksm: cmp_and_merge_page() optimizations
and cleanup" cleans up and slightly optimizes KSM.
- Roman Gushchin has separated the memcg-v1 and memcg-v2 code - lots of
code motion. The series (which also makes the memcg-v1 code
Kconfigurable) are
"mm: memcg: separate legacy cgroup v1 code and put under config
option" and
"mm: memcg: put cgroup v1-specific memcg data under CONFIG_MEMCG_V1"
- Dan Schatzberg's series "Add swappiness argument to memory.reclaim"
adds an additional feature to this cgroup-v2 control file.
- The series "Userspace controls soft-offline pages" from Jiaqi Yan
permits userspace to stop the kernel's automatic treatment of excessive
correctable memory errors. In order to permit userspace to monitor and
handle this situation.
- Kefeng Wang's series "mm: migrate: support poison recover from migrate
folio" teaches the kernel to appropriately handle migration from
poisoned source folios rather than simply panicing.
- SeongJae Park's series "Docs/damon: minor fixups and improvements"
does those things.
- In the series "mm/zsmalloc: change back to per-size_class lock"
Chengming Zhou improves zsmalloc's scalability and memory utilization.
- Vivek Kasireddy's series "mm/gup: Introduce memfd_pin_folios() for
pinning memfd folios" makes the GUP code use FOLL_PIN rather than bare
refcount increments. So these paes can first be moved aside if they
reside in the movable zone or a CMA block.
- Andrii Nakryiko has added a binary ioctl()-based API to /proc/pid/maps
for much faster reading of vma information. The series is "query VMAs
from /proc/<pid>/maps".
- In the series "mm: introduce per-order mTHP split counters" Lance Yang
improves the kernel's presentation of developer information related to
multisize THP splitting.
- Michael Ellerman has developed the series "Reimplement huge pages
without hugepd on powerpc (8xx, e500, book3s/64)". This permits
userspace to use all available huge page sizes.
- In the series "revert unconditional slab and page allocator fault
injection calls" Vlastimil Babka removes a performance-affecting and not
very useful feature from slab fault injection.
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCZp2C+QAKCRDdBJ7gKXxA
joTkAQDvjqOoFStqk4GU3OXMYB7WCU/ZQMFG0iuu1EEwTVDZ4QEA8CnG7seek1R3
xEoo+vw0sWWeLV3qzsxnCA1BJ8cTJA8=
=z0Lf
-----END PGP SIGNATURE-----
Merge tag 'mm-stable-2024-07-21-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
- In the series "mm: Avoid possible overflows in dirty throttling" Jan
Kara addresses a couple of issues in the writeback throttling code.
These fixes are also targetted at -stable kernels.
- Ryusuke Konishi's series "nilfs2: fix potential issues related to
reserved inodes" does that. This should actually be in the
mm-nonmm-stable tree, along with the many other nilfs2 patches. My
bad.
- More folio conversions from Kefeng Wang in the series "mm: convert to
folio_alloc_mpol()"
- Kemeng Shi has sent some cleanups to the writeback code in the series
"Add helper functions to remove repeated code and improve readability
of cgroup writeback"
- Kairui Song has made the swap code a little smaller and a little
faster in the series "mm/swap: clean up and optimize swap cache
index".
- In the series "mm/memory: cleanly support zeropage in
vm_insert_page*(), vm_map_pages*() and vmf_insert_mixed()" David
Hildenbrand has reworked the rather sketchy handling of the use of
the zeropage in MAP_SHARED mappings. I don't see any runtime effects
here - more a cleanup/understandability/maintainablity thing.
- Dev Jain has improved selftests/mm/va_high_addr_switch.c's handling
of higher addresses, for aarch64. The (poorly named) series is
"Restructure va_high_addr_switch".
- The core TLB handling code gets some cleanups and possible slight
optimizations in Bang Li's series "Add update_mmu_tlb_range() to
simplify code".
- Jane Chu has improved the handling of our
fake-an-unrecoverable-memory-error testing feature MADV_HWPOISON in
the series "Enhance soft hwpoison handling and injection".
- Jeff Johnson has sent a billion patches everywhere to add
MODULE_DESCRIPTION() to everything. Some landed in this pull.
- In the series "mm: cleanup MIGRATE_SYNC_NO_COPY mode", Kefeng Wang
has simplified migration's use of hardware-offload memory copying.
- Yosry Ahmed performs more folio API conversions in his series "mm:
zswap: trivial folio conversions".
- In the series "large folios swap-in: handle refault cases first",
Chuanhua Han inches us forward in the handling of large pages in the
swap code. This is a cleanup and optimization, working toward the end
objective of full support of large folio swapin/out.
- In the series "mm,swap: cleanup VMA based swap readahead window
calculation", Huang Ying has contributed some cleanups and a possible
fixlet to his VMA based swap readahead code.
- In the series "add mTHP support for anonymous shmem" Baolin Wang has
taught anonymous shmem mappings to use multisize THP. By default this
is a no-op - users must opt in vis sysfs controls. Dramatic
improvements in pagefault latency are realized.
- David Hildenbrand has some cleanups to our remaining use of
page_mapcount() in the series "fs/proc: move page_mapcount() to
fs/proc/internal.h".
- David also has some highmem accounting cleanups in the series
"mm/highmem: don't track highmem pages manually".
- Build-time fixes and cleanups from John Hubbard in the series
"cleanups, fixes, and progress towards avoiding "make headers"".
- Cleanups and consolidation of the core pagemap handling from Barry
Song in the series "mm: introduce pmd|pte_needs_soft_dirty_wp helpers
and utilize them".
- Lance Yang's series "Reclaim lazyfree THP without splitting" has
reduced the latency of the reclaim of pmd-mapped THPs under fairly
common circumstances. A 10x speedup is seen in a microbenchmark.
It does this by punting to aother CPU but I guess that's a win unless
all CPUs are pegged.
- hugetlb_cgroup cleanups from Xiu Jianfeng in the series
"mm/hugetlb_cgroup: rework on cftypes".
- Miaohe Lin's series "Some cleanups for memory-failure" does just that
thing.
- Someone other than SeongJae has developed a DAMON feature in Honggyu
Kim's series "DAMON based tiered memory management for CXL memory".
This adds DAMON features which may be used to help determine the
efficiency of our placement of CXL/PCIe attached DRAM.
- DAMON user API centralization and simplificatio work in SeongJae
Park's series "mm/damon: introduce DAMON parameters online commit
function".
- In the series "mm: page_type, zsmalloc and page_mapcount_reset()"
David Hildenbrand does some maintenance work on zsmalloc - partially
modernizing its use of pageframe fields.
- Kefeng Wang provides more folio conversions in the series "mm: remove
page_maybe_dma_pinned() and page_mkclean()".
- More cleanup from David Hildenbrand, this time in the series
"mm/memory_hotplug: use PageOffline() instead of PageReserved() for
!ZONE_DEVICE". It "enlightens memory hotplug more about PageOffline()
pages" and permits the removal of some virtio-mem hacks.
- Barry Song's series "mm: clarify folio_add_new_anon_rmap() and
__folio_add_anon_rmap()" is a cleanup to the anon folio handling in
preparation for mTHP (multisize THP) swapin.
- Kefeng Wang's series "mm: improve clear and copy user folio"
implements more folio conversions, this time in the area of large
folio userspace copying.
- The series "Docs/mm/damon/maintaier-profile: document a mailing tool
and community meetup series" tells people how to get better involved
with other DAMON developers. From SeongJae Park.
- A large series ("kmsan: Enable on s390") from Ilya Leoshkevich does
that.
- David Hildenbrand sends along more cleanups, this time against the
migration code. The series is "mm/migrate: move NUMA hinting fault
folio isolation + checks under PTL".
- Jan Kara has found quite a lot of strangenesses and minor errors in
the readahead code. He addresses this in the series "mm: Fix various
readahead quirks".
- SeongJae Park's series "selftests/damon: test DAMOS tried regions and
{min,max}_nr_regions" adds features and addresses errors in DAMON's
self testing code.
- Gavin Shan has found a userspace-triggerable WARN in the pagecache
code. The series "mm/filemap: Limit page cache size to that supported
by xarray" addresses this. The series is marked cc:stable.
- Chengming Zhou's series "mm/ksm: cmp_and_merge_page() optimizations
and cleanup" cleans up and slightly optimizes KSM.
- Roman Gushchin has separated the memcg-v1 and memcg-v2 code - lots of
code motion. The series (which also makes the memcg-v1 code
Kconfigurable) are "mm: memcg: separate legacy cgroup v1 code and put
under config option" and "mm: memcg: put cgroup v1-specific memcg
data under CONFIG_MEMCG_V1"
- Dan Schatzberg's series "Add swappiness argument to memory.reclaim"
adds an additional feature to this cgroup-v2 control file.
- The series "Userspace controls soft-offline pages" from Jiaqi Yan
permits userspace to stop the kernel's automatic treatment of
excessive correctable memory errors. In order to permit userspace to
monitor and handle this situation.
- Kefeng Wang's series "mm: migrate: support poison recover from
migrate folio" teaches the kernel to appropriately handle migration
from poisoned source folios rather than simply panicing.
- SeongJae Park's series "Docs/damon: minor fixups and improvements"
does those things.
- In the series "mm/zsmalloc: change back to per-size_class lock"
Chengming Zhou improves zsmalloc's scalability and memory
utilization.
- Vivek Kasireddy's series "mm/gup: Introduce memfd_pin_folios() for
pinning memfd folios" makes the GUP code use FOLL_PIN rather than
bare refcount increments. So these paes can first be moved aside if
they reside in the movable zone or a CMA block.
- Andrii Nakryiko has added a binary ioctl()-based API to
/proc/pid/maps for much faster reading of vma information. The series
is "query VMAs from /proc/<pid>/maps".
- In the series "mm: introduce per-order mTHP split counters" Lance
Yang improves the kernel's presentation of developer information
related to multisize THP splitting.
- Michael Ellerman has developed the series "Reimplement huge pages
without hugepd on powerpc (8xx, e500, book3s/64)". This permits
userspace to use all available huge page sizes.
- In the series "revert unconditional slab and page allocator fault
injection calls" Vlastimil Babka removes a performance-affecting and
not very useful feature from slab fault injection.
* tag 'mm-stable-2024-07-21-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (411 commits)
mm/mglru: fix ineffective protection calculation
mm/zswap: fix a white space issue
mm/hugetlb: fix kernel NULL pointer dereference when migrating hugetlb folio
mm/hugetlb: fix possible recursive locking detected warning
mm/gup: clear the LRU flag of a page before adding to LRU batch
mm/numa_balancing: teach mpol_to_str about the balancing mode
mm: memcg1: convert charge move flags to unsigned long long
alloc_tag: fix page_ext_get/page_ext_put sequence during page splitting
lib: reuse page_ext_data() to obtain codetag_ref
lib: add missing newline character in the warning message
mm/mglru: fix overshooting shrinker memory
mm/mglru: fix div-by-zero in vmpressure_calc_level()
mm/kmemleak: replace strncpy() with strscpy()
mm, page_alloc: put should_fail_alloc_page() back behing CONFIG_FAIL_PAGE_ALLOC
mm, slab: put should_failslab() back behind CONFIG_SHOULD_FAILSLAB
mm: ignore data-race in __swap_writepage
hugetlbfs: ensure generic_hugetlb_get_unmapped_area() returns higher address than mmap_min_addr
mm: shmem: rename mTHP shmem counters
mm: swap_state: use folio_alloc_mpol() in __read_swap_cache_async()
mm/migrate: putback split folios when numa hint migration fails
...
|
||
|
Linus Torvalds
|
1ca995edf8 |
seccomp updates for v6.11-rc1
- interrupt SECCOMP_IOCTL_NOTIF_RECV when all users exit (Andrei Vagin) - Update selftests to check for expected NOTIF_RECV exits (Andrei Vagin) -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEpcP2jyKd1g9yPm4TiXL039xtwCYFAmaVTOkACgkQiXL039xt wCayUA//fJTZUq+idihdKMql9SEwYh0uIJQpGOxxBEesUksZUM4alTCswzmheLFL q9BxlWWJJfUsp3djeZK+0vnDv3izaR+LfA1JPEJf64ImbympbEenVXK0ZkmVrTqg bNAlD5c/LVpzYtB7cnOaglq18uUja6/E+EQvNYz5NLHrIhYYCieJZIiFATkHQ9Lj 3Wq3g9FWEa5pZxpKbEI3UA2HllADnmHeb/Z78Zdvyue5lOOvsBIheQfL4m0pW38x xgBWNglIg7b+X+YgwYSv8w50Lhn4SJVtIynWnwzBz19qFJRQL7oJRj1zyFHZPCwZ ajHVIj5LOuts/BYxSiGzczxVqZaAqeOyCY5e8G+Mjk5ZD5kLYznbbcrIFIUIaHpx rpRD/TVVwJ3PHsOIpWHwrXKgoKnbe/0n8lJT+Ehnm/2lLrlGyZj9hLyl6/+JsizE dGIWgE2emykYI+52IRRYSZaw4hLb+CU52d1vd5a35wUk1ie5fcVGZAWnaul23x0I maQtXcyB6tYuhX3oPnxoxFVqGvCKGi3Tc5N+Vg4JR/RzTy2H7fZ02DRZq8Vs0QST EgO3cpCD3035qxkK6ivaV4ebPJjkL158D/+uFyne+PWQlSfrmXJvhfggPFA+Oqtb y8PTUV73+HxDiruXbGZ7MD8C7d+ZvGI/D+xheohYrijhivcXxcc= =tlFN -----END PGP SIGNATURE----- Merge tag 'seccomp-v6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull seccomp updates from Kees Cook: - interrupt SECCOMP_IOCTL_NOTIF_RECV when all users exit (Andrei Vagin) - Update selftests to check for expected NOTIF_RECV exits (Andrei Vagin) * tag 'seccomp-v6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: selftests/seccomp: check that a zombie leader doesn't affect others selftests/seccomp: add test for NOTIF_RECV and unused filters seccomp: release task filters when the task exits seccomp: interrupt SECCOMP_IOCTL_NOTIF_RECV when all users have exited |
||
|
Oleg Nesterov
|
d73d003521 |
memcg: mm_update_next_owner: move for_each_thread() into try_to_set_owner()
mm_update_next_owner() checks the children / real_parent->children to avoid the "everything else" loop in the likely case, but this won't work if a child/sibling has a zombie leader with ->mm == NULL. Move the for_each_thread() logic into try_to_set_owner(), if nothing else this makes the children/siblings/everything searches more consistent. Link: https://lkml.kernel.org/r/20240626152930.GA17936@redhat.com Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jinliang Zheng <alexjlzheng@tencent.com> Cc: Mateusz Guzik <mjguzik@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Tycho Andersen <tandersen@netflix.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
Oleg Nesterov
|
2a22b773b1 |
memcg: mm_update_next_owner: kill the "retry" logic
Add the new helper, try_to_set_owner(), which tries to update mm->owner once we see c->mm == mm. This way mm_update_next_owner() doesn't need to restart the list_for_each_entry/for_each_process loops from the very beginning if it races with exit/exec, it can just continue. Unlike the current code, try_to_set_owner() re-checks tsk->mm == mm before it drops tasklist_lock, so it doesn't need get/put_task_struct(). Link: https://lkml.kernel.org/r/20240626152924.GA17933@redhat.com Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jinliang Zheng <alexjlzheng@tencent.com> Cc: Mateusz Guzik <mjguzik@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Tycho Andersen <tandersen@netflix.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
Jinliang Zheng
|
76ba6acfcc |
mm: optimize the redundant loop of mm_update_owner_next()
When mm_update_owner_next() is racing with swapoff (try_to_unuse()) or /proc or ptrace or page migration (get_task_mm()), it is impossible to find an appropriate task_struct in the loop whose mm_struct is the same as the target mm_struct. If the above race condition is combined with the stress-ng-zombie and stress-ng-dup tests, such a long loop can easily cause a Hard Lockup in write_lock_irq() for tasklist_lock. Recognize this situation in advance and exit early. Link: https://lkml.kernel.org/r/20240620122123.3877432-1-alexjlzheng@tencent.com Signed-off-by: Jinliang Zheng <alexjlzheng@tencent.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Mateusz Guzik <mjguzik@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tycho Andersen <tandersen@netflix.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
Jinliang Zheng
|
cf3f9a593d |
mm: optimize the redundant loop of mm_update_owner_next()
When mm_update_owner_next() is racing with swapoff (try_to_unuse()) or /proc or ptrace or page migration (get_task_mm()), it is impossible to find an appropriate task_struct in the loop whose mm_struct is the same as the target mm_struct. If the above race condition is combined with the stress-ng-zombie and stress-ng-dup tests, such a long loop can easily cause a Hard Lockup in write_lock_irq() for tasklist_lock. Recognize this situation in advance and exit early. Link: https://lkml.kernel.org/r/20240620122123.3877432-1-alexjlzheng@tencent.com Signed-off-by: Jinliang Zheng <alexjlzheng@tencent.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Mateusz Guzik <mjguzik@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tycho Andersen <tandersen@netflix.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
Andrei Vagin
|
bfafe5efa9 |
seccomp: release task filters when the task exits
Previously, seccomp filters were released in release_task(), which required the process to exit and its zombie to be collected. However, exited threads/processes can't trigger any seccomp events, making it more logical to release filters upon task exits. This adjustment simplifies scenarios where a parent is tracing its child process. The parent process can now handle all events from a seccomp listening descriptor and then call wait to collect a child zombie. seccomp_filter_release takes the siglock to avoid races with seccomp_sync_threads. There was an idea to bypass taking the lock by checking PF_EXITING, but it can be set without holding siglock if threads have SIGNAL_GROUP_EXIT. This means it can happen concurently with seccomp_filter_release. This change also fixes another minor problem. Suppose that a group leader installs the new filter without SECCOMP_FILTER_FLAG_TSYNC, exits, and becomes a zombie. Without this change, SECCOMP_FILTER_FLAG_TSYNC from any other thread can never succeed, seccomp_can_sync_threads() will check a zombie leader and is_ancestor() will fail. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrei Vagin <avagin@google.com> Link: https://lore.kernel.org/r/20240628021014.231976-3-avagin@google.com Reviewed-by: Tycho Andersen <tandersen@netflix.com> Signed-off-by: Kees Cook <kees@kernel.org> |
||
|
Linus Torvalds
|
2ef32ad224 |
virtio: features, fixes, cleanups
Several new features here: - virtio-net is finally supported in vduse. - Virtio (balloon and mem) interaction with suspend is improved - vhost-scsi now handles signals better/faster. Fixes, cleanups all over the place. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> -----BEGIN PGP SIGNATURE----- iQFDBAABCAAtFiEEXQn9CHHI+FuUyooNKB8NuNKNVGkFAmZN570PHG1zdEByZWRo YXQuY29tAAoJECgfDbjSjVRp2JUH/1K3fZOHymop6Y5Z3USFS7YdlF+dniedY/vg TKyWERkXOlxq1d9DVxC0mN7tk72DweuWI0YJjLXofrEW1VuW29ecSbyFXxpeWJls b7ErffxDAFRas5jkMCngD8TuFnbEegU0mGP5kbiHpEndBydQ2hH99Gg0x7swW+cE xsvU5zonCCLwLGIP2DrVrn9qGOHtV6o8eZfVKDVXfvicn3lFBkUSxlwEYsO9RMup aKxV4FT2Pb1yBicwBK4TH1oeEXqEGy1YLEn+kAHRbgoC/5L0/LaiqrkzwzwwOIPj uPGkacf8CIbX0qZo5EzD8kvfcYL1xhU3eT9WBmpp2ZwD+4bINd4= =nax1 -----END PGP SIGNATURE----- Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost Pull virtio updates from Michael Tsirkin: "Several new features here: - virtio-net is finally supported in vduse - virtio (balloon and mem) interaction with suspend is improved - vhost-scsi now handles signals better/faster And fixes, cleanups all over the place" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (48 commits) virtio-pci: Check if is_avq is NULL virtio: delete vq in vp_find_vqs_msix() when request_irq() fails MAINTAINERS: add Eugenio Pérez as reviewer vhost-vdpa: Remove usage of the deprecated ida_simple_xx() API vp_vdpa: don't allocate unused msix vectors sound: virtio: drop owner assignment fuse: virtio: drop owner assignment scsi: virtio: drop owner assignment rpmsg: virtio: drop owner assignment nvdimm: virtio_pmem: drop owner assignment wifi: mac80211_hwsim: drop owner assignment vsock/virtio: drop owner assignment net: 9p: virtio: drop owner assignment net: virtio: drop owner assignment net: caif: virtio: drop owner assignment misc: nsm: drop owner assignment iommu: virtio: drop owner assignment drm/virtio: drop owner assignment gpio: virtio: drop owner assignment firmware: arm_scmi: virtio: drop owner assignment ... |
||
|
Mike Christie
|
240a1853b4 |
kernel: Remove signal hacks for vhost_tasks
This removes the signal/coredump hacks added for vhost_tasks in:
Commit f9010dbdce91 ("fork, vhost: Use CLONE_THREAD to fix freezer/ps regression")
When that patch was added vhost_tasks did not handle SIGKILL and would
try to ignore/clear the signal and continue on until the device's close
function was called. In the previous patches vhost_tasks and the vhost
drivers were converted to support SIGKILL by cleaning themselves up and
exiting. The hacks are no longer needed so this removes them.
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20240316004707.45557-10-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
|
||
|
Joel Granados
|
11a921909f |
kernel misc: Remove the now superfluous sentinel elements from ctl_table array
This commit comes at the tail end of a greater effort to remove the empty elements at the end of the ctl_table arrays (sentinels) which will reduce the overall build time size of the kernel and run time memory bloat by ~64 bytes per sentinel (further information Link : https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) Remove the sentinel from ctl_table arrays. Reduce by one the values used to compare the size of the adjusted arrays. Signed-off-by: Joel Granados <j.granados@samsung.com> |
||
|
Linus Torvalds
|
b5683a37c8 |
vfs-6.9.pidfd
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCZem4/wAKCRCRxhvAZXjc
opnBAQCaQWwxjT0VLHebPniw6tel/KYlZ9jH9kBQwLrk1pembwEA+BsCY2C8YS4a
75v9jOPxr+Z8j1SjxwwubcONPyqYXwQ=
=+Wa3
-----END PGP SIGNATURE-----
Merge tag 'vfs-6.9.pidfd' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull pdfd updates from Christian Brauner:
- Until now pidfds could only be created for thread-group leaders but
not for threads. There was no technical reason for this. We simply
had no users that needed support for this. Now we do have users that
need support for this.
This introduces a new PIDFD_THREAD flag for pidfd_open(). If that
flag is set pidfd_open() creates a pidfd that refers to a specific
thread.
In addition, we now allow clone() and clone3() to be called with
CLONE_PIDFD | CLONE_THREAD which wasn't possible before.
A pidfd that refers to an individual thread differs from a pidfd that
refers to a thread-group leader:
(1) Pidfds are pollable. A task may poll a pidfd and get notified
when the task has exited.
For thread-group leader pidfds the polling task is woken if the
thread-group is empty. In other words, if the thread-group
leader task exits when there are still threads alive in its
thread-group the polling task will not be woken when the
thread-group leader exits but rather when the last thread in the
thread-group exits.
For thread-specific pidfds the polling task is woken if the
thread exits.
(2) Passing a thread-group leader pidfd to pidfd_send_signal() will
generate thread-group directed signals like kill(2) does.
Passing a thread-specific pidfd to pidfd_send_signal() will
generate thread-specific signals like tgkill(2) does.
The default scope of the signal is thus determined by the type
of the pidfd.
Since use-cases exist where the default scope of the provided
pidfd needs to be overriden the following flags are added to
pidfd_send_signal():
- PIDFD_SIGNAL_THREAD
Send a thread-specific signal.
- PIDFD_SIGNAL_THREAD_GROUP
Send a thread-group directed signal.
- PIDFD_SIGNAL_PROCESS_GROUP
Send a process-group directed signal.
The scope change will only work if the struct pid is actually
used for this scope.
For example, in order to send a thread-group directed signal the
provided pidfd must be used as a thread-group leader and
similarly for PIDFD_SIGNAL_PROCESS_GROUP the struct pid must be
used as a process group leader.
- Move pidfds from the anonymous inode infrastructure to a tiny pseudo
filesystem. This will unblock further work that we weren't able to do
simply because of the very justified limitations of anonymous inodes.
Moving pidfds to a tiny pseudo filesystem allows for statx on pidfds
to become useful for the first time. They can now be compared by
inode number which are unique for the system lifetime.
Instead of stashing struct pid in file->private_data we can now stash
it in inode->i_private. This makes it possible to introduce concepts
that operate on a process once all file descriptors have been closed.
A concrete example is kill-on-last-close. Another side-effect is that
file->private_data is now freed up for per-file options for pidfds.
Now, each struct pid will refer to a different inode but the same
struct pid will refer to the same inode if it's opened multiple
times. In contrast to now where each struct pid refers to the same
inode.
The tiny pseudo filesystem is not visible anywhere in userspace
exactly like e.g., pipefs and sockfs. There's no lookup, there's no
complex inode operations, nothing. Dentries and inodes are always
deleted when the last pidfd is closed.
We allocate a new inode and dentry for each struct pid and we reuse
that inode and dentry for all pidfds that refer to the same struct
pid. The code is entirely optional and fairly small. If it's not
selected we fallback to anonymous inodes. Heavily inspired by nsfs.
The dentry and inode allocation mechanism is moved into generic
infrastructure that is now shared between nsfs and pidfs. The
path_from_stashed() helper must be provided with a stashing location,
an inode number, a mount, and the private data that is supposed to be
used and it will provide a path that can be passed to dentry_open().
The helper will try retrieve an existing dentry from the provided
stashing location. If a valid dentry is found it is reused. If not a
new one is allocated and we try to stash it in the provided location.
If this fails we retry until we either find an existing dentry or the
newly allocated dentry could be stashed. Subsequent openers of the
same namespace or task are then able to reuse it.
- Currently it is only possible to get notified when a task has exited,
i.e., become a zombie and userspace gets notified with EPOLLIN. We
now also support waiting until the task has been reaped, notifying
userspace with EPOLLHUP.
- Ensure that ESRCH is reported for getfd if a task is exiting instead
of the confusing EBADF.
- Various smaller cleanups to pidfd functions.
* tag 'vfs-6.9.pidfd' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (23 commits)
libfs: improve path_from_stashed()
libfs: add stashed_dentry_prune()
libfs: improve path_from_stashed() helper
pidfs: convert to path_from_stashed() helper
nsfs: convert to path_from_stashed() helper
libfs: add path_from_stashed()
pidfd: add pidfs
pidfd: move struct pidfd_fops
pidfd: allow to override signal scope in pidfd_send_signal()
pidfd: change pidfd_send_signal() to respect PIDFD_THREAD
signal: fill in si_code in prepare_kill_siginfo()
selftests: add ESRCH tests for pidfd_getfd()
pidfd: getfd should always report ESRCH if a task is exiting
pidfd: clone: allow CLONE_THREAD | CLONE_PIDFD together
pidfd: exit: kill the no longer used thread_group_exited()
pidfd: change do_notify_pidfd() to use __wake_up(poll_to_key(EPOLLIN))
pid: kill the obsolete PIDTYPE_PID code in transfer_pid()
pidfd: kill the no longer needed do_notify_pidfd() in de_thread()
pidfd_poll: report POLLHUP when pid_task() == NULL
pidfd: implement PIDFD_THREAD flag for pidfd_open()
...
|
||
|
Oleg Nesterov
|
c1be35a16b |
exit: wait_task_zombie: kill the no longer necessary spin_lock_irq(siglock)
After the recent changes nobody use siglock to read the values protected by stats_lock, we can kill spin_lock_irq(¤t->sighand->siglock) and update the comment. With this patch only __exit_signal() and thread_group_start_cputime() take stats_lock under siglock. Link: https://lkml.kernel.org/r/20240123153359.GA21866@redhat.com Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Dylan Hatch <dylanbhatch@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
Oleg Nesterov
|
e2e8a142fb |
pidfd: exit: kill the no longer used thread_group_exited()
It was used by pidfd_poll() but now it has no callers.
If it finally finds a modular user we can revert this change, but note
that the comment above this helper and the changelog in 38fd525a4c61
("exit: Factor thread_group_exited out of pidfd_poll") are not accurate,
thread_group_exited() won't return true if all other threads have passed
exit_notify() and are zombies, it returns true only when all other threads
are completely gone. Not to mention that it can only work if the task
identified by @pid is a thread-group leader.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20240205174347.GA31461@redhat.com
Reviewed-by: Tycho Andersen <tandersen@netflix.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
||
|
Oleg Nesterov
|
64bef697d3 |
pidfd: implement PIDFD_THREAD flag for pidfd_open()
With this flag: - pidfd_open() doesn't require that the target task must be a thread-group leader - pidfd_poll() succeeds when the task exits and becomes a zombie (iow, passes exit_notify()), even if it is a leader and thread-group is not empty. This means that the behaviour of pidfd_poll(PIDFD_THREAD, pid-of-group-leader) is not well defined if it races with exec() from its sub-thread; pidfd_poll() can succeed or not depending on whether pidfd_task_exited() is called before or after exchange_tids(). Perhaps we can improve this behaviour later, pidfd_poll() can probably take sig->group_exec_task into account. But this doesn't really differ from the case when the leader exits before other threads (so pidfd_poll() succeeds) and then another thread execs and pidfd_poll() will block again. thread_group_exited() is no longer used, perhaps it can die. Co-developed-by: Tycho Andersen <tycho@tycho.pizza> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Link: https://lore.kernel.org/r/20240131132602.GA23641@redhat.com Tested-by: Tycho Andersen <tandersen@netflix.com> Reviewed-by: Tycho Andersen <tandersen@netflix.com> Signed-off-by: Christian Brauner <brauner@kernel.org> |
||
|
Linus Torvalds
|
78273df7f6 |
header cleanups for 6.8
The goal is to get sched.h down to a type only header, so the main thing happening in this patchset is splitting out various _types.h headers and dependency fixups, as well as moving some things out of sched.h to better locations. This is prep work for the memory allocation profiling patchset which adds new sched.h interdepencencies. Testing - it's been in -next, and fixes from pretty much all architectures have percolated in - nothing major. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEKnAFLkS8Qha+jvQrE6szbY3KbnYFAmWfBwwACgkQE6szbY3K bnZPwBAAmuRojXaeWxi01IPIOehSGDe68vw44PR9glEMZvxdnZuPOdvE4/+245/L bRKU2WBCjBUokUbV9msIShwRkFTZAmEMPNfPAAsFMA+VXeDYHKB+ZRdwTggNAQ+I SG6fZgh5m0HsewCDxU8oqVHkjVq4fXn0cy+aL6xLEd9gu67GoBzX2pDieS2Kvy6j jnyoKTxFwb+LTQgph0P4EIpq5I2umAsdLwdSR8EJ+8e9NiNvMo1pI00Lx/ntAnFZ JftWUJcMy3TQ5u1GkyfQN9y/yThX1bZK5GvmHS9SJ2Dkacaus5d+xaKCHtRuFS1I 7C6b8PsNgRczUMumBXus44HdlNfNs1yU3lvVxFvBIPE1qC9pYRHrkWIXXIocXLLC oxTEJ6B2G3BQZVQgLIA4fOaxMVhmvKffi/aEZLi9vN9VVosd1a6XNKI6KbyRnXFp GSs9qDqszhn5I3GYNlDNQTc/8UsRlhPFgS6nS0By6QnvxtGi9QkU2tBRBsXvqwCy cLoCYIhc2tvugHvld70dz26umiJ4rnmxGlobStNoigDvIKAIUt1UmIdr1so8P8eH xehnL9ZcOX6xnANDL0AqMFFHV6I58CJynhFdUoXfVQf/DWLGX48mpi9LVNsYBzsI CAwVOAQ0UjGrpdWmJ9ueY/ABYqg9vRjzaDEXQ+MhAYO55CLaVsg= =3tyT -----END PGP SIGNATURE----- Merge tag 'header_cleanup-2024-01-10' of https://evilpiepirate.org/git/bcachefs Pull header cleanups from Kent Overstreet: "The goal is to get sched.h down to a type only header, so the main thing happening in this patchset is splitting out various _types.h headers and dependency fixups, as well as moving some things out of sched.h to better locations. This is prep work for the memory allocation profiling patchset which adds new sched.h interdepencencies" * tag 'header_cleanup-2024-01-10' of https://evilpiepirate.org/git/bcachefs: (51 commits) Kill sched.h dependency on rcupdate.h kill unnecessary thread_info.h include Kill unnecessary kernel.h include preempt.h: Kill dependency on list.h rseq: Split out rseq.h from sched.h LoongArch: signal.c: add header file to fix build error restart_block: Trim includes lockdep: move held_lock to lockdep_types.h sem: Split out sem_types.h uidgid: Split out uidgid_types.h seccomp: Split out seccomp_types.h refcount: Split out refcount_types.h uapi/linux/resource.h: fix include x86/signal: kill dependency on time.h syscall_user_dispatch.h: split out *_types.h mm_types_task.h: Trim dependencies Split out irqflags_types.h ipc: Kill bogus dependency on spinlock.h shm: Slim down dependencies workqueue: Split out workqueue_types.h ... |
||
|
Matthew Wilcox (Oracle)
|
6dfeff09d5 |
wait: Remove uapi header file from main header file
There's really no overlap between uapi/linux/wait.h and linux/wait.h. There are two files which rely on the uapi file being implcitly included, so explicitly include it there and remove it from the main header file. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev> Reviewed-by: Christian Brauner <brauner@kernel.org> |
||
|
Jens Axboe
|
ae1914174a |
cred: get rid of CONFIG_DEBUG_CREDENTIALS
This code is rarely (never?) enabled by distros, and it hasn't caught anything in decades. Let's kill off this legacy debug code. Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Linus Torvalds
|
8f6f76a6a2 |
As usual, lots of singleton and doubleton patches all over the tree and
there's little I can say which isn't in the individual changelogs.
The lengthier patch series are
- "kdump: use generic functions to simplify crashkernel reservation in
arch", from Baoquan He. This is mainly cleanups and consolidation of
the "crashkernel=" kernel parameter handling.
- After much discussion, David Laight's "minmax: Relax type checks in
min() and max()" is here. Hopefully reduces some typecasting and the
use of min_t() and max_t().
- A group of patches from Oleg Nesterov which clean up and slightly fix
our handling of reads from /proc/PID/task/... and which remove
task_struct.therad_group.
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCZUQP9wAKCRDdBJ7gKXxA
jmOAAQDh8sxagQYocoVsSm28ICqXFeaY9Co1jzBIDdNesAvYVwD/c2DHRqJHEiS4
63BNcG3+hM9nwGJHb5lyh5m79nBMRg0=
=On4u
-----END PGP SIGNATURE-----
Merge tag 'mm-nonmm-stable-2023-11-02-14-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton:
"As usual, lots of singleton and doubleton patches all over the tree
and there's little I can say which isn't in the individual changelogs.
The lengthier patch series are
- 'kdump: use generic functions to simplify crashkernel reservation
in arch', from Baoquan He. This is mainly cleanups and
consolidation of the 'crashkernel=' kernel parameter handling
- After much discussion, David Laight's 'minmax: Relax type checks in
min() and max()' is here. Hopefully reduces some typecasting and
the use of min_t() and max_t()
- A group of patches from Oleg Nesterov which clean up and slightly
fix our handling of reads from /proc/PID/task/... and which remove
task_struct.thread_group"
* tag 'mm-nonmm-stable-2023-11-02-14-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (64 commits)
scripts/gdb/vmalloc: disable on no-MMU
scripts/gdb: fix usage of MOD_TEXT not defined when CONFIG_MODULES=n
.mailmap: add address mapping for Tomeu Vizoso
mailmap: update email address for Claudiu Beznea
tools/testing/selftests/mm/run_vmtests.sh: lower the ptrace permissions
.mailmap: map Benjamin Poirier's address
scripts/gdb: add lx_current support for riscv
ocfs2: fix a spelling typo in comment
proc: test ProtectionKey in proc-empty-vm test
proc: fix proc-empty-vm test with vsyscall
fs/proc/base.c: remove unneeded semicolon
do_io_accounting: use sig->stats_lock
do_io_accounting: use __for_each_thread()
ocfs2: replace BUG_ON() at ocfs2_num_free_extents() with ocfs2_error()
ocfs2: fix a typo in a comment
scripts/show_delta: add __main__ judgement before main code
treewide: mark stuff as __ro_after_init
fs: ocfs2: check status values
proc: test /proc/${pid}/statm
compiler.h: move __is_constexpr() to compiler.h
...
|
||
|
Linus Torvalds
|
ecae0bd517 |
Many singleton patches against the MM code. The patch series which are
included in this merge do the following:
- Kemeng Shi has contributed some compation maintenance work in the
series "Fixes and cleanups to compaction".
- Joel Fernandes has a patchset ("Optimize mremap during mutual
alignment within PMD") which fixes an obscure issue with mremap()'s
pagetable handling during a subsequent exec(), based upon an
implementation which Linus suggested.
- More DAMON/DAMOS maintenance and feature work from SeongJae Park i the
following patch series:
mm/damon: misc fixups for documents, comments and its tracepoint
mm/damon: add a tracepoint for damos apply target regions
mm/damon: provide pseudo-moving sum based access rate
mm/damon: implement DAMOS apply intervals
mm/damon/core-test: Fix memory leaks in core-test
mm/damon/sysfs-schemes: Do DAMOS tried regions update for only one apply interval
- In the series "Do not try to access unaccepted memory" Adrian Hunter
provides some fixups for the recently-added "unaccepted memory' feature.
To increase the feature's checking coverage. "Plug a few gaps where
RAM is exposed without checking if it is unaccepted memory".
- In the series "cleanups for lockless slab shrink" Qi Zheng has done
some maintenance work which is preparation for the lockless slab
shrinking code.
- Qi Zheng has redone the earlier (and reverted) attempt to make slab
shrinking lockless in the series "use refcount+RCU method to implement
lockless slab shrink".
- David Hildenbrand contributes some maintenance work for the rmap code
in the series "Anon rmap cleanups".
- Kefeng Wang does more folio conversions and some maintenance work in
the migration code. Series "mm: migrate: more folio conversion and
unification".
- Matthew Wilcox has fixed an issue in the buffer_head code which was
causing long stalls under some heavy memory/IO loads. Some cleanups
were added on the way. Series "Add and use bdev_getblk()".
- In the series "Use nth_page() in place of direct struct page
manipulation" Zi Yan has fixed a potential issue with the direct
manipulation of hugetlb page frames.
- In the series "mm: hugetlb: Skip initialization of gigantic tail
struct pages if freed by HVO" has improved our handling of gigantic
pages in the hugetlb vmmemmep optimizaton code. This provides
significant boot time improvements when significant amounts of gigantic
pages are in use.
- Matthew Wilcox has sent the series "Small hugetlb cleanups" - code
rationalization and folio conversions in the hugetlb code.
- Yin Fengwei has improved mlock()'s handling of large folios in the
series "support large folio for mlock"
- In the series "Expose swapcache stat for memcg v1" Liu Shixin has
added statistics for memcg v1 users which are available (and useful)
under memcg v2.
- Florent Revest has enhanced the MDWE (Memory-Deny-Write-Executable)
prctl so that userspace may direct the kernel to not automatically
propagate the denial to child processes. The series is named "MDWE
without inheritance".
- Kefeng Wang has provided the series "mm: convert numa balancing
functions to use a folio" which does what it says.
- In the series "mm/ksm: add fork-exec support for prctl" Stefan Roesch
makes is possible for a process to propagate KSM treatment across
exec().
- Huang Ying has enhanced memory tiering's calculation of memory
distances. This is used to permit the dax/kmem driver to use "high
bandwidth memory" in addition to Optane Data Center Persistent Memory
Modules (DCPMM). The series is named "memory tiering: calculate
abstract distance based on ACPI HMAT"
- In the series "Smart scanning mode for KSM" Stefan Roesch has
optimized KSM by teaching it to retain and use some historical
information from previous scans.
- Yosry Ahmed has fixed some inconsistencies in memcg statistics in the
series "mm: memcg: fix tracking of pending stats updates values".
- In the series "Implement IOCTL to get and optionally clear info about
PTEs" Peter Xu has added an ioctl to /proc/<pid>/pagemap which permits
us to atomically read-then-clear page softdirty state. This is mainly
used by CRIU.
- Hugh Dickins contributed the series "shmem,tmpfs: general maintenance"
- a bunch of relatively minor maintenance tweaks to this code.
- Matthew Wilcox has increased the use of the VMA lock over file-backed
page faults in the series "Handle more faults under the VMA lock". Some
rationalizations of the fault path became possible as a result.
- In the series "mm/rmap: convert page_move_anon_rmap() to
folio_move_anon_rmap()" David Hildenbrand has implemented some cleanups
and folio conversions.
- In the series "various improvements to the GUP interface" Lorenzo
Stoakes has simplified and improved the GUP interface with an eye to
providing groundwork for future improvements.
- Andrey Konovalov has sent along the series "kasan: assorted fixes and
improvements" which does those things.
- Some page allocator maintenance work from Kemeng Shi in the series
"Two minor cleanups to break_down_buddy_pages".
- In thes series "New selftest for mm" Breno Leitao has developed
another MM self test which tickles a race we had between madvise() and
page faults.
- In the series "Add folio_end_read" Matthew Wilcox provides cleanups
and an optimization to the core pagecache code.
- Nhat Pham has added memcg accounting for hugetlb memory in the series
"hugetlb memcg accounting".
- Cleanups and rationalizations to the pagemap code from Lorenzo
Stoakes, in the series "Abstract vma_merge() and split_vma()".
- Audra Mitchell has fixed issues in the procfs page_owner code's new
timestamping feature which was causing some misbehaviours. In the
series "Fix page_owner's use of free timestamps".
- Lorenzo Stoakes has fixed the handling of new mappings of sealed files
in the series "permit write-sealed memfd read-only shared mappings".
- Mike Kravetz has optimized the hugetlb vmemmap optimization in the
series "Batch hugetlb vmemmap modification operations".
- Some buffer_head folio conversions and cleanups from Matthew Wilcox in
the series "Finish the create_empty_buffers() transition".
- As a page allocator performance optimization Huang Ying has added
automatic tuning to the allocator's per-cpu-pages feature, in the series
"mm: PCP high auto-tuning".
- Roman Gushchin has contributed the patchset "mm: improve performance
of accounted kernel memory allocations" which improves their performance
by ~30% as measured by a micro-benchmark.
- folio conversions from Kefeng Wang in the series "mm: convert page
cpupid functions to folios".
- Some kmemleak fixups in Liu Shixin's series "Some bugfix about
kmemleak".
- Qi Zheng has improved our handling of memoryless nodes by keeping them
off the allocation fallback list. This is done in the series "handle
memoryless nodes more appropriately".
- khugepaged conversions from Vishal Moola in the series "Some
khugepaged folio conversions".
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCZULEMwAKCRDdBJ7gKXxA
jhQHAQCYpD3g849x69DmHnHWHm/EHQLvQmRMDeYZI+nx/sCJOwEAw4AKg0Oemv9y
FgeUPAD1oasg6CP+INZvCj34waNxwAc=
=E+Y4
-----END PGP SIGNATURE-----
Merge tag 'mm-stable-2023-11-01-14-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
"Many singleton patches against the MM code. The patch series which are
included in this merge do the following:
- Kemeng Shi has contributed some compation maintenance work in the
series 'Fixes and cleanups to compaction'
- Joel Fernandes has a patchset ('Optimize mremap during mutual
alignment within PMD') which fixes an obscure issue with mremap()'s
pagetable handling during a subsequent exec(), based upon an
implementation which Linus suggested
- More DAMON/DAMOS maintenance and feature work from SeongJae Park i
the following patch series:
mm/damon: misc fixups for documents, comments and its tracepoint
mm/damon: add a tracepoint for damos apply target regions
mm/damon: provide pseudo-moving sum based access rate
mm/damon: implement DAMOS apply intervals
mm/damon/core-test: Fix memory leaks in core-test
mm/damon/sysfs-schemes: Do DAMOS tried regions update for only one apply interval
- In the series 'Do not try to access unaccepted memory' Adrian
Hunter provides some fixups for the recently-added 'unaccepted
memory' feature. To increase the feature's checking coverage. 'Plug
a few gaps where RAM is exposed without checking if it is
unaccepted memory'
- In the series 'cleanups for lockless slab shrink' Qi Zheng has done
some maintenance work which is preparation for the lockless slab
shrinking code
- Qi Zheng has redone the earlier (and reverted) attempt to make slab
shrinking lockless in the series 'use refcount+RCU method to
implement lockless slab shrink'
- David Hildenbrand contributes some maintenance work for the rmap
code in the series 'Anon rmap cleanups'
- Kefeng Wang does more folio conversions and some maintenance work
in the migration code. Series 'mm: migrate: more folio conversion
and unification'
- Matthew Wilcox has fixed an issue in the buffer_head code which was
causing long stalls under some heavy memory/IO loads. Some cleanups
were added on the way. Series 'Add and use bdev_getblk()'
- In the series 'Use nth_page() in place of direct struct page
manipulation' Zi Yan has fixed a potential issue with the direct
manipulation of hugetlb page frames
- In the series 'mm: hugetlb: Skip initialization of gigantic tail
struct pages if freed by HVO' has improved our handling of gigantic
pages in the hugetlb vmmemmep optimizaton code. This provides
significant boot time improvements when significant amounts of
gigantic pages are in use
- Matthew Wilcox has sent the series 'Small hugetlb cleanups' - code
rationalization and folio conversions in the hugetlb code
- Yin Fengwei has improved mlock()'s handling of large folios in the
series 'support large folio for mlock'
- In the series 'Expose swapcache stat for memcg v1' Liu Shixin has
added statistics for memcg v1 users which are available (and
useful) under memcg v2
- Florent Revest has enhanced the MDWE (Memory-Deny-Write-Executable)
prctl so that userspace may direct the kernel to not automatically
propagate the denial to child processes. The series is named 'MDWE
without inheritance'
- Kefeng Wang has provided the series 'mm: convert numa balancing
functions to use a folio' which does what it says
- In the series 'mm/ksm: add fork-exec support for prctl' Stefan
Roesch makes is possible for a process to propagate KSM treatment
across exec()
- Huang Ying has enhanced memory tiering's calculation of memory
distances. This is used to permit the dax/kmem driver to use 'high
bandwidth memory' in addition to Optane Data Center Persistent
Memory Modules (DCPMM). The series is named 'memory tiering:
calculate abstract distance based on ACPI HMAT'
- In the series 'Smart scanning mode for KSM' Stefan Roesch has
optimized KSM by teaching it to retain and use some historical
information from previous scans
- Yosry Ahmed has fixed some inconsistencies in memcg statistics in
the series 'mm: memcg: fix tracking of pending stats updates
values'
- In the series 'Implement IOCTL to get and optionally clear info
about PTEs' Peter Xu has added an ioctl to /proc/<pid>/pagemap
which permits us to atomically read-then-clear page softdirty
state. This is mainly used by CRIU
- Hugh Dickins contributed the series 'shmem,tmpfs: general
maintenance', a bunch of relatively minor maintenance tweaks to
this code
- Matthew Wilcox has increased the use of the VMA lock over
file-backed page faults in the series 'Handle more faults under the
VMA lock'. Some rationalizations of the fault path became possible
as a result
- In the series 'mm/rmap: convert page_move_anon_rmap() to
folio_move_anon_rmap()' David Hildenbrand has implemented some
cleanups and folio conversions
- In the series 'various improvements to the GUP interface' Lorenzo
Stoakes has simplified and improved the GUP interface with an eye
to providing groundwork for future improvements
- Andrey Konovalov has sent along the series 'kasan: assorted fixes
and improvements' which does those things
- Some page allocator maintenance work from Kemeng Shi in the series
'Two minor cleanups to break_down_buddy_pages'
- In thes series 'New selftest for mm' Breno Leitao has developed
another MM self test which tickles a race we had between madvise()
and page faults
- In the series 'Add folio_end_read' Matthew Wilcox provides cleanups
and an optimization to the core pagecache code
- Nhat Pham has added memcg accounting for hugetlb memory in the
series 'hugetlb memcg accounting'
- Cleanups and rationalizations to the pagemap code from Lorenzo
Stoakes, in the series 'Abstract vma_merge() and split_vma()'
- Audra Mitchell has fixed issues in the procfs page_owner code's new
timestamping feature which was causing some misbehaviours. In the
series 'Fix page_owner's use of free timestamps'
- Lorenzo Stoakes has fixed the handling of new mappings of sealed
files in the series 'permit write-sealed memfd read-only shared
mappings'
- Mike Kravetz has optimized the hugetlb vmemmap optimization in the
series 'Batch hugetlb vmemmap modification operations'
- Some buffer_head folio conversions and cleanups from Matthew Wilcox
in the series 'Finish the create_empty_buffers() transition'
- As a page allocator performance optimization Huang Ying has added
automatic tuning to the allocator's per-cpu-pages feature, in the
series 'mm: PCP high auto-tuning'
- Roman Gushchin has contributed the patchset 'mm: improve
performance of accounted kernel memory allocations' which improves
their performance by ~30% as measured by a micro-benchmark
- folio conversions from Kefeng Wang in the series 'mm: convert page
cpupid functions to folios'
- Some kmemleak fixups in Liu Shixin's series 'Some bugfix about
kmemleak'
- Qi Zheng has improved our handling of memoryless nodes by keeping
them off the allocation fallback list. This is done in the series
'handle memoryless nodes more appropriately'
- khugepaged conversions from Vishal Moola in the series 'Some
khugepaged folio conversions'"
[ bcachefs conflicts with the dynamically allocated shrinkers have been
resolved as per Stephen Rothwell in
https://lore.kernel.org/all/20230913093553.4290421e@canb.auug.org.au/
with help from Qi Zheng.
The clone3 test filtering conflict was half-arsed by yours truly ]
* tag 'mm-stable-2023-11-01-14-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (406 commits)
mm/damon/sysfs: update monitoring target regions for online input commit
mm/damon/sysfs: remove requested targets when online-commit inputs
selftests: add a sanity check for zswap
Documentation: maple_tree: fix word spelling error
mm/vmalloc: fix the unchecked dereference warning in vread_iter()
zswap: export compression failure stats
Documentation: ubsan: drop "the" from article title
mempolicy: migration attempt to match interleave nodes
mempolicy: mmap_lock is not needed while migrating folios
mempolicy: alloc_pages_mpol() for NUMA policy without vma
mm: add page_rmappable_folio() wrapper
mempolicy: remove confusing MPOL_MF_LAZY dead code
mempolicy: mpol_shared_policy_init() without pseudo-vma
mempolicy trivia: use pgoff_t in shared mempolicy tree
mempolicy trivia: slightly more consistent naming
mempolicy trivia: delete those ancient pr_debug()s
mempolicy: fix migrate_pages(2) syscall return nr_failed
kernfs: drop shared NUMA mempolicy hooks
hugetlbfs: drop shared NUMA mempolicy pretence
mm/damon/sysfs-test: add a unit test for damon_sysfs_set_targets()
...
|
||
|
Oleg Nesterov
|
8e1f385104 |
kill task_struct->thread_group
The last user was removed by the previous patch. Link: https://lkml.kernel.org/r/20230826111409.GA23243@redhat.com Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
Mateusz Guzik
|
bc0c335760 |
mm: remove remnants of SPLIT_RSS_COUNTING
The feature got retired in f1a7941243c1 ("mm: convert mm's rss stats into
percpu_counter"), but the patch failed to fully clean it up.
Link: https://lkml.kernel.org/r/20230823170556.2281747-1-mjguzik@gmail.com
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Acked-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
||
|
Jens Axboe
|
2e521a2064 |
exit: add internal include file with helpers
Move struct wait_opts and waitid_info into kernel/exit.h, and include function declarations for the recently added helpers. Make them non-static as well. This is in preparation for adding a waitid operation through io_uring. With the abtracted helpers, this is now possible. Signed-off-by: Jens Axboe <axboe@kernel.dk> |
||
|
Jens Axboe
|
eda7e9d409 |
exit: add kernel_waitid_prepare() helper
Move the setup logic out of kernel_waitid(), and into a separate helper. No functional changes intended in this patch. Signed-off-by: Jens Axboe <axboe@kernel.dk> |
||
|
Jens Axboe
|
06a101ca45 |
exit: move core of do_wait() into helper
Rather than have a maze of gotos, put the actual logic in __do_wait() and have do_wait() loop deal with waitqueue setup/teardown and whether to call __do_wait() again. No functional changes intended in this patch. Acked-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> |
||
|
Jens Axboe
|
9d900d4ea3 |
exit: abstract out should_wake helper for child_wait_callback()
Abstract out the helper that decides if we should wake up following a wake_up() callback on our internal waitqueue. No functional changes intended in this patch. Acked-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> |
||
|
Mike Christie
|
f9010dbdce |
fork, vhost: Use CLONE_THREAD to fix freezer/ps regression
When switching from kthreads to vhost_tasks two bugs were added:
1. The vhost worker tasks's now show up as processes so scripts doing
ps or ps a would not incorrectly detect the vhost task as another
process. 2. kthreads disabled freeze by setting PF_NOFREEZE, but
vhost tasks's didn't disable or add support for them.
To fix both bugs, this switches the vhost task to be thread in the
process that does the VHOST_SET_OWNER ioctl, and has vhost_worker call
get_signal to support SIGKILL/SIGSTOP and freeze signals. Note that
SIGKILL/STOP support is required because CLONE_THREAD requires
CLONE_SIGHAND which requires those 2 signals to be supported.
This is a modified version of the patch written by Mike Christie
<michael.christie@oracle.com> which was a modified version of patch
originally written by Linus.
Much of what depended upon PF_IO_WORKER now depends on PF_USER_WORKER.
Including ignoring signals, setting up the register state, and having
get_signal return instead of calling do_group_exit.
Tidied up the vhost_task abstraction so that the definition of
vhost_task only needs to be visible inside of vhost_task.c. Making
it easier to review the code and tell what needs to be done where.
As part of this the main loop has been moved from vhost_worker into
vhost_task_fn. vhost_worker now returns true if work was done.
The main loop has been updated to call get_signal which handles
SIGSTOP, freezing, and collects the message that tells the thread to
exit as part of process exit. This collection clears
__fatal_signal_pending. This collection is not guaranteed to
clear signal_pending() so clear that explicitly so the schedule()
sleeps.
For now the vhost thread continues to exist and run work until the
last file descriptor is closed and the release function is called as
part of freeing struct file. To avoid hangs in the coredump
rendezvous and when killing threads in a multi-threaded exec. The
coredump code and de_thread have been modified to ignore vhost threads.
Remvoing the special case for exec appears to require teaching
vhost_dev_flush how to directly complete transactions in case
the vhost thread is no longer running.
Removing the special case for coredump rendezvous requires either the
above fix needed for exec or moving the coredump rendezvous into
get_signal.
Fixes: 6e890c5d5021 ("vhost: use vhost_tasks for worker threads")
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Co-developed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
||
|
Linus Torvalds
|
d579c468d7 |
tracing updates for 6.4:
- User events are finally ready!
After lots of collaboration between various parties, we finally locked
down on a stable interface for user events that can also work with user
space only tracing. This is implemented by telling the kernel (or user
space library, but that part is user space only and not part of this
patch set), where the variable is that the application uses to know if
something is listening to the trace. There's also an interface to tell
the kernel about these events, which will show up in the
/sys/kernel/tracing/events/user_events/ directory, where it can be
enabled. When it's enabled, the kernel will update the variable, to tell
the application to start writing to the kernel.
See https://lwn.net/Articles/927595/
- Cleaned up the direct trampolines code to simplify arm64 addition of
direct trampolines. Direct trampolines use the ftrace interface but
instead of jumping to the ftrace trampoline, applications (mostly BPF)
can register their own trampoline for performance reasons.
- Some updates to the fprobe infrastructure. fprobes are more efficient than
kprobes, as it does not need to save all the registers that kprobes on
ftrace do. More work needs to be done before the fprobes will be exposed
as dynamic events.
- More updates to references to the obsolete path of
/sys/kernel/debug/tracing for the new /sys/kernel/tracing path.
- Add a seq_buf_do_printk() helper to seq_bufs, to print a large buffer line
by line instead of all at once. There's users in production kernels that
have a large data dump that originally used printk() directly, but the
data dump was larger than what printk() allowed as a single print.
Using seq_buf() to do the printing fixes that.
- Add /sys/kernel/tracing/touched_functions that shows all functions that
was every traced by ftrace or a direct trampoline. This is used for
debugging issues where a traced function could have caused a crash by
a bpf program or live patching.
- Add a "fields" option that is similar to "raw" but outputs the fields of
the events. It's easier to read by humans.
- Some minor fixes and clean ups.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCZEr36xQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6quZHAQCzuqnn2S8DsPd3Sy1vKIYaj0uajW5D
Kz1oUJH4F0H7kgEA8XwXkdtfKpOXWc/ZH4LWfL7Orx2wJZJQMV9dVqEPDAE=
=w0Z1
-----END PGP SIGNATURE-----
Merge tag 'trace-v6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing updates from Steven Rostedt:
- User events are finally ready!
After lots of collaboration between various parties, we finally
locked down on a stable interface for user events that can also work
with user space only tracing.
This is implemented by telling the kernel (or user space library, but
that part is user space only and not part of this patch set), where
the variable is that the application uses to know if something is
listening to the trace.
There's also an interface to tell the kernel about these events,
which will show up in the /sys/kernel/tracing/events/user_events/
directory, where it can be enabled.
When it's enabled, the kernel will update the variable, to tell the
application to start writing to the kernel.
See https://lwn.net/Articles/927595/
- Cleaned up the direct trampolines code to simplify arm64 addition of
direct trampolines.
Direct trampolines use the ftrace interface but instead of jumping to
the ftrace trampoline, applications (mostly BPF) can register their
own trampoline for performance reasons.
- Some updates to the fprobe infrastructure. fprobes are more efficient
than kprobes, as it does not need to save all the registers that
kprobes on ftrace do. More work needs to be done before the fprobes
will be exposed as dynamic events.
- More updates to references to the obsolete path of
/sys/kernel/debug/tracing for the new /sys/kernel/tracing path.
- Add a seq_buf_do_printk() helper to seq_bufs, to print a large buffer
line by line instead of all at once.
There are users in production kernels that have a large data dump
that originally used printk() directly, but the data dump was larger
than what printk() allowed as a single print.
Using seq_buf() to do the printing fixes that.
- Add /sys/kernel/tracing/touched_functions that shows all functions
that was every traced by ftrace or a direct trampoline. This is used
for debugging issues where a traced function could have caused a
crash by a bpf program or live patching.
- Add a "fields" option that is similar to "raw" but outputs the fields
of the events. It's easier to read by humans.
- Some minor fixes and clean ups.
* tag 'trace-v6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (41 commits)
ring-buffer: Sync IRQ works before buffer destruction
tracing: Add missing spaces in trace_print_hex_seq()
ring-buffer: Ensure proper resetting of atomic variables in ring_buffer_reset_online_cpus
recordmcount: Fix memory leaks in the uwrite function
tracing/user_events: Limit max fault-in attempts
tracing/user_events: Prevent same address and bit per process
tracing/user_events: Ensure bit is cleared on unregister
tracing/user_events: Ensure write index cannot be negative
seq_buf: Add seq_buf_do_printk() helper
tracing: Fix print_fields() for __dyn_loc/__rel_loc
tracing/user_events: Set event filter_type from type
ring-buffer: Clearly check null ptr returned by rb_set_head_page()
tracing: Unbreak user events
tracing/user_events: Use print_format_fields() for trace output
tracing/user_events: Align structs with tabs for readability
tracing/user_events: Limit global user_event count
tracing/user_events: Charge event allocs to cgroups
tracing/user_events: Update documentation for ABI
tracing/user_events: Use write ABI in example
tracing/user_events: Add ABI self-test
...
|
||
|
Beau Belgrave
|
fd593511cd |
tracing/user_events: Track fork/exec/exit for mm lifetime
During tracefs discussions it was decided instead of requiring a mapping within a user-process to track the lifetime of memory descriptors we should hook the appropriate calls. Do this by adding the minimal stubs required for task fork, exec, and exit. Currently this is just a NOP. Future patches will implement these calls fully. Link: https://lkml.kernel.org/r/20230328235219.203-3-beaub@linux.microsoft.com Suggested-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> |
||
|
Nicholas Piggin
|
aa464ba9a1 |
lazy tlb: introduce lazy tlb mm refcount helper functions
Add explicit _lazy_tlb annotated functions for lazy tlb mm refcounting. This makes the lazy tlb mm references more obvious, and allows the refcounting scheme to be modified in later changes. There is no functional change with this patch. Link: https://lkml.kernel.org/r/20230203071837.1136453-3-npiggin@gmail.com Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
Linus Torvalds
|
8bf1a529cd |
arm64 updates for 6.3:
- Support for arm64 SME 2 and 2.1. SME2 introduces a new 512-bit architectural register (ZT0, for the look-up table feature) that Linux needs to save/restore. - Include TPIDR2 in the signal context and add the corresponding kselftests. - Perf updates: Arm SPEv1.2 support, HiSilicon uncore PMU updates, ACPI support to the Marvell DDR and TAD PMU drivers, reset DTM_PMU_CONFIG (ARM CMN) at probe time. - Support for DYNAMIC_FTRACE_WITH_CALL_OPS on arm64. - Permit EFI boot with MMU and caches on. Instead of cleaning the entire loaded kernel image to the PoC and disabling the MMU and caches before branching to the kernel bare metal entry point, leave the MMU and caches enabled and rely on EFI's cacheable 1:1 mapping of all of system RAM to populate the initial page tables. - Expose the AArch32 (compat) ELF_HWCAP features to user in an arm64 kernel (the arm32 kernel only defines the values). - Harden the arm64 shadow call stack pointer handling: stash the shadow stack pointer in the task struct on interrupt, load it directly from this structure. - Signal handling cleanups to remove redundant validation of size information and avoid reading the same data from userspace twice. - Refactor the hwcap macros to make use of the automatically generated ID registers. It should make new hwcaps writing less error prone. - Further arm64 sysreg conversion and some fixes. - arm64 kselftest fixes and improvements. - Pointer authentication cleanups: don't sign leaf functions, unify asm-arch manipulation. - Pseudo-NMI code generation optimisations. - Minor fixes for SME and TPIDR2 handling. - Miscellaneous updates: ARCH_FORCE_MAX_ORDER is now selectable, replace strtobool() to kstrtobool() in the cpufeature.c code, apply dynamic shadow call stack in two passes, intercept pfn changes in set_pte_at() without the required break-before-make sequence, attempt to dump all instructions on unhandled kernel faults. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEE5RElWfyWxS+3PLO2a9axLQDIXvEFAmP0/QsACgkQa9axLQDI XvG+gA/+JDVEH9wRzAIZvbp9hSuohPc48xgAmIMP1eiVB0/5qeRjYAJwS33H0rXS BPC2kj9IBy/eQeM9ICg0nFd0zYznSVacITqe6NrqeJ1F+ftS4rrHdfxd+J7kIoCs V2L8e+BJvmHdhmNV2qMAgJdGlfxfQBA7fv2cy52HKYcouoOh1AUVR/x+yXVXAsCd qJP3+dlUKccgm/oc5unEC1eZ49u8O+EoasqOyfG6K5udMgzhEX3K6imT9J3hw0WT UjstYkx5uGS/prUrRCQAX96VCHoZmzEDKtQuHkHvQXEYXsYPF3ldbR2CziNJnHe7 QfSkjJlt8HAtExA+BkwEe9i0MQO/2VF5qsa2e4fA6l7uqGu3LOtS/jJd23C9n9fR Id8aBMeN6S8+MjqRA9L2uf4t6e4ISEHoG9ZRdc4WOwloxEEiJoIeun+7bHdOSZLj AFdHFCz4NXiiwC0UP0xPDI2YeCLqt5np7HmnrUqwzRpVO8UUagiJD8TIpcBSjBN9 J68eidenHUW7/SlIeaMKE2lmo8AUEAJs9AorDSugF19/ThJcQdx7vT2UAZjeVB3j 1dbbwajnlDOk/w8PQC4thFp5/MDlfst0htS3WRwa+vgkweE2EAdTU4hUZ8qEP7FQ smhYtlT1xUSTYDTqoaG/U2OWR6/UU79wP0jgcOsHXTuyYrtPI/Q= =VmXL -----END PGP SIGNATURE----- Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: - Support for arm64 SME 2 and 2.1. SME2 introduces a new 512-bit architectural register (ZT0, for the look-up table feature) that Linux needs to save/restore - Include TPIDR2 in the signal context and add the corresponding kselftests - Perf updates: Arm SPEv1.2 support, HiSilicon uncore PMU updates, ACPI support to the Marvell DDR and TAD PMU drivers, reset DTM_PMU_CONFIG (ARM CMN) at probe time - Support for DYNAMIC_FTRACE_WITH_CALL_OPS on arm64 - Permit EFI boot with MMU and caches on. Instead of cleaning the entire loaded kernel image to the PoC and disabling the MMU and caches before branching to the kernel bare metal entry point, leave the MMU and caches enabled and rely on EFI's cacheable 1:1 mapping of all of system RAM to populate the initial page tables - Expose the AArch32 (compat) ELF_HWCAP features to user in an arm64 kernel (the arm32 kernel only defines the values) - Harden the arm64 shadow call stack pointer handling: stash the shadow stack pointer in the task struct on interrupt, load it directly from this structure - Signal handling cleanups to remove redundant validation of size information and avoid reading the same data from userspace twice - Refactor the hwcap macros to make use of the automatically generated ID registers. It should make new hwcaps writing less error prone - Further arm64 sysreg conversion and some fixes - arm64 kselftest fixes and improvements - Pointer authentication cleanups: don't sign leaf functions, unify asm-arch manipulation - Pseudo-NMI code generation optimisations - Minor fixes for SME and TPIDR2 handling - Miscellaneous updates: ARCH_FORCE_MAX_ORDER is now selectable, replace strtobool() to kstrtobool() in the cpufeature.c code, apply dynamic shadow call stack in two passes, intercept pfn changes in set_pte_at() without the required break-before-make sequence, attempt to dump all instructions on unhandled kernel faults * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (130 commits) arm64: fix .idmap.text assertion for large kernels kselftest/arm64: Don't require FA64 for streaming SVE+ZA tests kselftest/arm64: Copy whole EXTRA context arm64: kprobes: Drop ID map text from kprobes blacklist perf: arm_spe: Print the version of SPE detected perf: arm_spe: Add support for SPEv1.2 inverted event filtering perf: Add perf_event_attr::config3 arm64/sme: Fix __finalise_el2 SMEver check drivers/perf: fsl_imx8_ddr_perf: Remove set-but-not-used variable arm64/signal: Only read new data when parsing the ZT context arm64/signal: Only read new data when parsing the ZA context arm64/signal: Only read new data when parsing the SVE context arm64/signal: Avoid rereading context frame sizes arm64/signal: Make interface for restore_fpsimd_context() consistent arm64/signal: Remove redundant size validation from parse_user_sigframe() arm64/signal: Don't redundantly verify FPSIMD magic arm64/cpufeature: Use helper macros to specify hwcaps arm64/cpufeature: Always use symbolic name for feature value in hwcaps arm64/sysreg: Initial unsigned annotations for ID registers arm64/sysreg: Initial annotation of signed ID registers ... |
||
|
Mark Rutland
|
c27cd083cf |
Compiler attributes: GCC cold function alignment workarounds
Contemporary versions of GCC (e.g. GCC 12.2.0) drop the alignment specified by '-falign-functions=N' for functions marked with the __cold__ attribute, and potentially for callees of __cold__ functions as these may be implicitly marked as __cold__ by the compiler. LLVM appears to respect '-falign-functions=N' in such cases. This has been reported to GCC in bug 88345: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88345 ... which also covers alignment being dropped when '-Os' is used, which will be addressed in a separate patch. Currently, use of '-falign-functions=N' is limited to CONFIG_FUNCTION_ALIGNMENT, which is largely used for performance and/or analysis reasons (e.g. with CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_64B), but isn't necessary for correct functionality. However, this dropped alignment isn't great for the performance and/or analysis cases. Subsequent patches will use CONFIG_FUNCTION_ALIGNMENT as part of arm64's ftrace implementation, which will require all instrumented functions to be aligned to at least 8-bytes. This patch works around the dropped alignment by avoiding the use of the __cold__ attribute when CONFIG_FUNCTION_ALIGNMENT is non-zero, and by specifically aligning abort(), which GCC implicitly marks as __cold__. As the __cold macro is now dependent upon config options (which is against the policy described at the top of compiler_attributes.h), it is moved into compiler_types.h. I've tested this by building and booting a kernel configured with defconfig + CONFIG_EXPERT=y + CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_64B=y, and looking for misaligned text symbols in /proc/kallsyms: * arm64: Before: # uname -rm 6.2.0-rc3 aarch64 # grep ' [Tt] ' /proc/kallsyms | grep -iv '[048c]0 [Tt] ' | wc -l 5009 After: # uname -rm 6.2.0-rc3-00001-g2a2bedf8bfa9 aarch64 # grep ' [Tt] ' /proc/kallsyms | grep -iv '[048c]0 [Tt] ' | wc -l 919 * x86_64: Before: # uname -rm 6.2.0-rc3 x86_64 # grep ' [Tt] ' /proc/kallsyms | grep -iv '[048c]0 [Tt] ' | wc -l 11537 After: # uname -rm 6.2.0-rc3-00001-g2a2bedf8bfa9 x86_64 # grep ' [Tt] ' /proc/kallsyms | grep -iv '[048c]0 [Tt] ' | wc -l 2805 There's clearly a substantial reduction in the number of misaligned symbols. From manual inspection, the remaining unaligned text labels are a combination of ACPICA functions (due to the use of '-Os'), static call trampolines, and non-function labels in assembly, which will be dealt with in subsequent patches. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Florent Revest <revest@chromium.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Will Deacon <will@kernel.org> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Link: https://lore.kernel.org/r/20230123134603.1064407-3-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> |
||
|
Nicholas Piggin
|
001c28e571 |
exit: Detect and fix irq disabled state in oops
If a task oopses with irqs disabled, this can cause various cascading
problems in the oops path such as sleep-from-invalid warnings, and
potentially worse.
Since commit 0258b5fd7c712 ("coredump: Limit coredumps to a single
thread group"), the unconditional irq enable in coredump_task_exit()
will "fix" the irq state to be enabled early in do_exit(), so currently
this may not be triggerable, but that is coincidental and fragile.
Detect and fix the irqs_disabled() condition in the oops path before
calling do_exit(), similarly to the way in_atomic() is handled.
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Link: https://lore.kernel.org/lkml/20221004094401.708299-1-npiggin@gmail.com/
|
||
|
Kees Cook
|
7535b832c6 |
exit: Use READ_ONCE() for all oops/warn limit reads
Use a temporary variable to take full advantage of READ_ONCE() behavior. Without this, the report (and even the test) might be out of sync with the initial test. Reported-by: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/lkml/Y5x7GXeluFmZ8E0E@hirez.programming.kicks-ass.net Fixes: 9fc9e278a5c0 ("panic: Introduce warn_limit") Fixes: d4ccd54d28d3 ("exit: Put an upper limit on how often we can oops") Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Jann Horn <jannh@google.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Petr Mladek <pmladek@suse.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Marco Elver <elver@google.com> Cc: tangmeng <tangmeng@uniontech.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Kees Cook <keescook@chromium.org> |
||
|
Kees Cook
|
de92f65719 |
exit: Allow oops_limit to be disabled
In preparation for keeping oops_limit logic in sync with warn_limit, have oops_limit == 0 disable checking the Oops counter. Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: "Jason A. Donenfeld" <Jason@zx2c4.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Huang Ying <ying.huang@intel.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: linux-doc@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> |