<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-dev/ipc, branch master</title>
<subtitle>Linux kernel development work - see feature branches</subtitle>
<id>https://git.zx2c4.com/linux-dev/atom/ipc?h=master</id>
<link rel='self' href='https://git.zx2c4.com/linux-dev/atom/ipc?h=master'/>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/'/>
<updated>2022-10-28T20:37:22Z</updated>
<entry>
<title>ipc/msg.c: fix percpu_counter use after free</title>
<updated>2022-10-28T20:37:22Z</updated>
<author>
<name>Andrew Morton</name>
<email>akpm@linux-foundation.org</email>
</author>
<published>2022-10-21T04:19:22Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=64b4c411a6c7a5f27555bfc2d6310b87bde3db67'/>
<id>urn:sha1:64b4c411a6c7a5f27555bfc2d6310b87bde3db67</id>
<content type='text'>
These percpu counters are referenced in free_ipcs-&gt;freeque, so destroy
them later.

Fixes: 72d1e611082e ("ipc/msg: mitigate the lock contention with percpu counter")
Reported-by: syzbot+96e659d35b9d6b541152@syzkaller.appspotmail.com
Tested-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Jiebin Sun &lt;jiebin.sun@intel.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'mm-nonmm-stable-2022-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2022-10-12T18:00:22Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-12T18:00:22Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=676cb4957396411fdb7aba906d5f950fc3de7cc9'/>
<id>urn:sha1:676cb4957396411fdb7aba906d5f950fc3de7cc9</id>
<content type='text'>
Pull non-MM updates from Andrew Morton:

 - hfs and hfsplus kmap API modernization (Fabio Francesco)

 - make crash-kexec work properly when invoked from an NMI-time panic
   (Valentin Schneider)

 - ntfs bugfixes (Hawkins Jiawei)

 - improve IPC msg scalability by replacing atomic_t's with percpu
   counters (Jiebin Sun)

 - nilfs2 cleanups (Minghao Chi)

 - lots of other single patches all over the tree!

* tag 'mm-nonmm-stable-2022-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (71 commits)
  include/linux/entry-common.h: remove has_signal comment of arch_do_signal_or_restart() prototype
  proc: test how it holds up with mapping'less process
  mailmap: update Frank Rowand email address
  ia64: mca: use strscpy() is more robust and safer
  init/Kconfig: fix unmet direct dependencies
  ia64: update config files
  nilfs2: replace WARN_ONs by nilfs_error for checkpoint acquisition failure
  fork: remove duplicate included header files
  init/main.c: remove unnecessary (void*) conversions
  proc: mark more files as permanent
  nilfs2: remove the unneeded result variable
  nilfs2: delete unnecessary checks before brelse()
  checkpatch: warn for non-standard fixes tag style
  usr/gen_init_cpio.c: remove unnecessary -1 values from int file
  ipc/msg: mitigate the lock contention with percpu counter
  percpu: add percpu_counter_add_local and percpu_counter_sub_local
  fs/ocfs2: fix repeated words in comments
  relay: use kvcalloc to alloc page array in relay_alloc_page_array
  proc: make config PROC_CHILDREN depend on PROC_FS
  fs: uninline inode_maybe_inc_iversion()
  ...
</content>
</entry>
<entry>
<title>Merge tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2022-10-11T00:53:04Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-11T00:53:04Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=27bc50fc90647bbf7b734c3fc306a5e61350da53'/>
<id>urn:sha1:27bc50fc90647bbf7b734c3fc306a5e61350da53</id>
<content type='text'>
Pull MM updates from Andrew Morton:

 - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in
   linux-next for a couple of months without, to my knowledge, any
   negative reports (or any positive ones, come to that).

 - Also the Maple Tree from Liam Howlett. An overlapping range-based
   tree for vmas. It it apparently slightly more efficient in its own
   right, but is mainly targeted at enabling work to reduce mmap_lock
   contention.

   Liam has identified a number of other tree users in the kernel which
   could be beneficially onverted to mapletrees.

   Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat
   at [1]. This has yet to be addressed due to Liam's unfortunately
   timed vacation. He is now back and we'll get this fixed up.

 - Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer. It uses
   clang-generated instrumentation to detect used-unintialized bugs down
   to the single bit level.

   KMSAN keeps finding bugs. New ones, as well as the legacy ones.

 - Yang Shi adds a userspace mechanism (madvise) to induce a collapse of
   memory into THPs.

 - Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to
   support file/shmem-backed pages.

 - userfaultfd updates from Axel Rasmussen

 - zsmalloc cleanups from Alexey Romanov

 - cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and
   memory-failure

 - Huang Ying adds enhancements to NUMA balancing memory tiering mode's
   page promotion, with a new way of detecting hot pages.

 - memcg updates from Shakeel Butt: charging optimizations and reduced
   memory consumption.

 - memcg cleanups from Kairui Song.

 - memcg fixes and cleanups from Johannes Weiner.

 - Vishal Moola provides more folio conversions

 - Zhang Yi removed ll_rw_block() :(

 - migration enhancements from Peter Xu

 - migration error-path bugfixes from Huang Ying

 - Aneesh Kumar added ability for a device driver to alter the memory
   tiering promotion paths. For optimizations by PMEM drivers, DRM
   drivers, etc.

 - vma merging improvements from Jakub Matěn.

 - NUMA hinting cleanups from David Hildenbrand.

 - xu xin added aditional userspace visibility into KSM merging
   activity.

 - THP &amp; KSM code consolidation from Qi Zheng.

 - more folio work from Matthew Wilcox.

 - KASAN updates from Andrey Konovalov.

 - DAMON cleanups from Kaixu Xia.

 - DAMON work from SeongJae Park: fixes, cleanups.

 - hugetlb sysfs cleanups from Muchun Song.

 - Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core.

Link: https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com [1]

* tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (555 commits)
  hugetlb: allocate vma lock for all sharable vmas
  hugetlb: take hugetlb vma_lock when clearing vma_lock-&gt;vma pointer
  hugetlb: fix vma lock handling during split vma and range unmapping
  mglru: mm/vmscan.c: fix imprecise comments
  mm/mglru: don't sync disk for each aging cycle
  mm: memcontrol: drop dead CONFIG_MEMCG_SWAP config symbol
  mm: memcontrol: use do_memsw_account() in a few more places
  mm: memcontrol: deprecate swapaccounting=0 mode
  mm: memcontrol: don't allocate cgroup swap arrays when memcg is disabled
  mm/secretmem: remove reduntant return value
  mm/hugetlb: add available_huge_pages() func
  mm: remove unused inline functions from include/linux/mm_inline.h
  selftests/vm: add selftest for MADV_COLLAPSE of uffd-minor memory
  selftests/vm: add file/shmem MADV_COLLAPSE selftest for cleared pmd
  selftests/vm: add thp collapse shmem testing
  selftests/vm: add thp collapse file and tmpfs testing
  selftests/vm: modularize thp collapse memory operations
  selftests/vm: dedup THP helpers
  mm/khugepaged: add tracepoint to hpage_collapse_scan_file()
  mm/madvise: add file and shmem support to MADV_COLLAPSE
  ...
</content>
</entry>
<entry>
<title>Merge tag 'retire_mq_sysctls-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace</title>
<updated>2022-10-09T23:10:22Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-09T23:10:22Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=86fb9c53d82f1dadf960553a3bd351de6173911f'/>
<id>urn:sha1:86fb9c53d82f1dadf960553a3bd351de6173911f</id>
<content type='text'>
Pull mqueue fix from Eric Biederman:
 "A fix for an unlikely but possible memory leak"

* tag 'retire_mq_sysctls-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  ipc: mqueue: fix possible memory leak in init_mqueue_fs()
</content>
</entry>
<entry>
<title>ipc/msg: mitigate the lock contention with percpu counter</title>
<updated>2022-10-03T21:21:44Z</updated>
<author>
<name>Jiebin Sun</name>
<email>jiebin.sun@intel.com</email>
</author>
<published>2022-09-13T19:25:38Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=72d1e611082eda18689106a0c192f2827072713c'/>
<id>urn:sha1:72d1e611082eda18689106a0c192f2827072713c</id>
<content type='text'>
The msg_bytes and msg_hdrs atomic counters are frequently updated when IPC
msg queue is in heavy use, causing heavy cache bounce and overhead. 
Change them to percpu_counter greatly improve the performance.  Since
there is one percpu struct per namespace, additional memory cost is
minimal.  Reading of the count done in msgctl call, which is infrequent. 
So the need to sum up the counts in each CPU is infrequent.

Apply the patch and test the pts/stress-ng-1.4.0
-- system v message passing (160 threads).

Score gain: 3.99x

CPU: ICX 8380 x 2 sockets
Core number: 40 x 2 physical cores
Benchmark: pts/stress-ng-1.4.0
-- system v message passing (160 threads)

[akpm@linux-foundation.org: coding-style cleanups]
[jiebin.sun@intel.com: avoid negative value by overflow in msginfo]
  Link: https://lkml.kernel.org/r/20220920150809.4014944-1-jiebin.sun@intel.com
[akpm@linux-foundation.org: fix min() warnings]
Link: https://lkml.kernel.org/r/20220913192538.3023708-3-jiebin.sun@intel.com
Signed-off-by: Jiebin Sun &lt;jiebin.sun@intel.com&gt;
Reviewed-by: Tim Chen &lt;tim.c.chen@linux.intel.com&gt;
Cc: Alexander Mikhalitsyn &lt;alexander.mikhalitsyn@virtuozzo.com&gt;
Cc: Alexey Gladkov &lt;legion@kernel.org&gt;
Cc: Christoph Lameter &lt;cl@linux.com&gt;
Cc: Davidlohr Bueso &lt;dave@stgolabs.net&gt;
Cc: Dennis Zhou &lt;dennis@kernel.org&gt;
Cc: "Eric W . Biederman" &lt;ebiederm@xmission.com&gt;
Cc: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Cc: Shakeel Butt &lt;shakeelb@google.com&gt;
Cc: Tejun Heo &lt;tj@kernel.org&gt;
Cc: Vasily Averin &lt;vasily.averin@linux.dev&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>ipc: mqueue: remove unnecessary conditionals</title>
<updated>2022-10-03T21:21:42Z</updated>
<author>
<name>Jingyu Wang</name>
<email>jingyuwang_vip@163.com</email>
</author>
<published>2022-09-08T18:54:52Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=5758478a3d3c42a78ee9ddc4b08db3e968a68058'/>
<id>urn:sha1:5758478a3d3c42a78ee9ddc4b08db3e968a68058</id>
<content type='text'>
iput() already handles null and non-null parameters, so there is no need
to use if().

Link: https://lkml.kernel.org/r/20220908185452.76590-1-jingyuwang_vip@163.com
Signed-off-by: Jingyu Wang &lt;jingyuwang_vip@163.com&gt;
Acked-by: Roman Gushchin &lt;roman.gushchin@linux.dev&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>ipc/shm: use VMA iterator instead of linked list</title>
<updated>2022-09-27T02:46:21Z</updated>
<author>
<name>Liam R. Howlett</name>
<email>Liam.Howlett@Oracle.com</email>
</author>
<published>2022-09-06T19:48:58Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=01293a62bae2fa55c09cebf5a771eab7219171c3'/>
<id>urn:sha1:01293a62bae2fa55c09cebf5a771eab7219171c3</id>
<content type='text'>
The VMA iterator is faster than the linked llist, and it can be walked
even when VMAs are being removed from the address space, so there's no
need to keep track of 'next'.

Link: https://lkml.kernel.org/r/20220906194824.2110408-46-Liam.Howlett@oracle.com
Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Signed-off-by: Liam R. Howlett &lt;Liam.Howlett@Oracle.com&gt;
Tested-by: Yu Zhao &lt;yuzhao@google.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: David Hildenbrand &lt;david@redhat.com&gt;
Cc: David Howells &lt;dhowells@redhat.com&gt;
Cc: Davidlohr Bueso &lt;dave@stgolabs.net&gt;
Cc: SeongJae Park &lt;sj@kernel.org&gt;
Cc: Sven Schnelle &lt;svens@linux.ibm.com&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>ipc/util.c: cleanup and improve sysvipc_find_ipc()</title>
<updated>2022-09-12T04:55:05Z</updated>
<author>
<name>Manfred Spraul</name>
<email>manfred@colorfullife.com</email>
</author>
<published>2022-08-05T11:57:33Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=58b5c203360799e181325f3f8ce212de80ebf304'/>
<id>urn:sha1:58b5c203360799e181325f3f8ce212de80ebf304</id>
<content type='text'>
sysvipc_find_ipc() can be simplified further:

- It uses a for() loop to locate the next entry in the idr.
  This can be replaced with idr_get_next().

- It receives two parameters (pos - which is actually
  an idr index and not a position, and new_pos, which
  is really a position).
  One parameter is sufficient.

Link: https://lore.kernel.org/all/20210903052020.3265-3-manfred@colorfullife.com/
Link: https://lkml.kernel.org/r/20220805115733.104763-1-manfred@colorfullife.com
Signed-off-by: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Acked-by: Davidlohr Bueso &lt;dave@stgolabs.net&gt;
Acked-by: Waiman Long &lt;longman@redhat.com&gt;
Cc: "Eric W . Biederman" &lt;ebiederm@xmission.com&gt;
Cc: &lt;1vier1@web.de&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'mm-nonmm-stable-2022-08-06-2' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2022-08-07T17:03:24Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-08-07T17:03:24Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=eb5699ba31558bdb2cee6ebde3d0a68091e47dce'/>
<id>urn:sha1:eb5699ba31558bdb2cee6ebde3d0a68091e47dce</id>
<content type='text'>
Pull misc updates from Andrew Morton:
 "Updates to various subsystems which I help look after. lib, ocfs2,
  fatfs, autofs, squashfs, procfs, etc. A relatively small amount of
  material this time"

* tag 'mm-nonmm-stable-2022-08-06-2' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (72 commits)
  scripts/gdb: ensure the absolute path is generated on initial source
  MAINTAINERS: kunit: add David Gow as a maintainer of KUnit
  mailmap: add linux.dev alias for Brendan Higgins
  mailmap: update Kirill's email
  profile: setup_profiling_timer() is moslty not implemented
  ocfs2: fix a typo in a comment
  ocfs2: use the bitmap API to simplify code
  ocfs2: remove some useless functions
  lib/mpi: fix typo 'the the' in comment
  proc: add some (hopefully) insightful comments
  bdi: remove enum wb_congested_state
  kernel/hung_task: fix address space of proc_dohung_task_timeout_secs
  lib/lzo/lzo1x_compress.c: replace ternary operator with min() and min_t()
  squashfs: support reading fragments in readahead call
  squashfs: implement readahead
  squashfs: always build "file direct" version of page actor
  Revert "squashfs: provide backing_dev_info in order to disable read-ahead"
  fs/ocfs2: Fix spelling typo in comment
  ia64: old_rr4 added under CONFIG_HUGETLB_PAGE
  proc: fix test for "vsyscall=xonly" boot option
  ...
</content>
</entry>
<entry>
<title>ipc: mqueue: fix possible memory leak in init_mqueue_fs()</title>
<updated>2022-07-19T22:17:35Z</updated>
<author>
<name>Hangyu Hua</name>
<email>hbh25y@gmail.com</email>
</author>
<published>2022-07-15T06:23:01Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=c579d60f0d0cd87552f64fdebe68b5d941d20309'/>
<id>urn:sha1:c579d60f0d0cd87552f64fdebe68b5d941d20309</id>
<content type='text'>
commit db7cfc380900 ("ipc: Free mq_sysctls if ipc namespace creation
failed")

Here's a similar memory leak to the one fixed by the patch above.
retire_mq_sysctls need to be called when init_mqueue_fs fails after
setup_mq_sysctls.

Fixes: dc55e35f9e81 ("ipc: Store mqueue sysctls in the ipc namespace")
Signed-off-by: Hangyu Hua &lt;hbh25y@gmail.com&gt;
Link: https://lkml.kernel.org/r/20220715062301.19311-1-hbh25y@gmail.com
Signed-off-by: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
</content>
</entry>
</feed>
