Commit Graph

729 Commits

Author SHA1 Message Date
Linus Torvalds
617a814f14 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
  ...
2024-09-21 07:29:05 -07:00
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>
2024-09-01 20:25:49 -07:00
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>
2024-09-01 20:25:49 -07:00
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>
2024-08-02 10:55:04 -07:00
Linus Torvalds
fbc90c042c 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
  ...
2024-07-21 17:15:46 -07:00
Linus Torvalds
1ca995edf8 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
2024-07-16 13:12:16 -07:00
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>
2024-07-04 18:05:58 -07:00
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>
2024-07-04 18:05:57 -07:00
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>
2024-07-03 19:30:15 -07:00
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>
2024-07-03 12:29:24 -07:00
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>
2024-06-28 09:37:11 -07:00
Linus Torvalds
2ef32ad224 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
  ...
2024-05-23 12:04:36 -07:00
Mike Christie
240a1853b4 kernel: Remove signal hacks for vhost_tasks
This removes the signal/coredump hacks added for vhost_tasks in:

Commit f9010dbdce ("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>
2024-05-22 08:31:15 -04:00
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>
2024-04-24 09:43:53 +02:00
Linus Torvalds
b5683a37c8 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()
  ...
2024-03-11 10:21:06 -07:00
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(&current->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>
2024-02-07 21:20:33 -08:00
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 38fd525a4c
("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>
2024-02-06 14:02:51 +01:00
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>
2024-02-02 13:12:28 +01:00
Linus Torvalds
78273df7f6 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
  ...
2024-01-10 16:43:55 -08:00
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>
2023-12-20 19:26:31 -05:00
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>
2023-12-15 14:19:48 -08:00
Linus Torvalds
8f6f76a6a2 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
  ...
2023-11-02 20:53:31 -10:00
Linus Torvalds
ecae0bd517 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()
  ...
2023-11-02 19:38:47 -10:00
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>
2023-10-04 10:41:56 -07:00
Mateusz Guzik
bc0c335760 mm: remove remnants of SPLIT_RSS_COUNTING
The feature got retired in f1a7941243 ("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>
2023-10-04 10:32:20 -07:00