<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/mm/kasan/quarantine.c, branch v6.18.22</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v6.18.22</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v6.18.22'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2024-02-24T01:27:12+00:00</updated>
<entry>
<title>kasan: revert eviction of stack traces in generic mode</title>
<updated>2024-02-24T01:27:12+00:00</updated>
<author>
<name>Marco Elver</name>
<email>elver@google.com</email>
</author>
<published>2024-01-29T10:07:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=711d349174fd5cf906955249dd0163635e144a1e'/>
<id>urn:sha1:711d349174fd5cf906955249dd0163635e144a1e</id>
<content type='text'>
This partially reverts commits cc478e0b6bdf, 63b85ac56a64, 08d7c94d9635,
a414d4286f34, and 773688a6cb24 to make use of variable-sized stack depot
records, since eviction of stack entries from stack depot forces fixed-
sized stack records.  Care was taken to retain the code cleanups by the
above commits.

Eviction was added to generic KASAN as a response to alleviating the
additional memory usage from fixed-sized stack records, but this still
uses more memory than previously.

With the re-introduction of variable-sized records for stack depot, we can
just switch back to non-evictable stack records again, and return back to
the previous performance and memory usage baseline.

Before (observed after a KASAN kernel boot):

  pools: 597
  refcounted_allocations: 17547
  refcounted_frees: 6477
  refcounted_in_use: 11070
  freelist_size: 3497
  persistent_count: 12163
  persistent_bytes: 1717008

After:

  pools: 319
  refcounted_allocations: 0
  refcounted_frees: 0
  refcounted_in_use: 0
  freelist_size: 0
  persistent_count: 29397
  persistent_bytes: 5183536

As can be seen from the counters, with a generic KASAN config, refcounted
allocations and evictions are no longer used.  Due to using variable-sized
records, I observe a reduction of 278 stack depot pools (saving 4448 KiB)
with my test setup.

Link: https://lkml.kernel.org/r/20240129100708.39460-2-elver@google.com
Fixes: cc478e0b6bdf ("kasan: avoid resetting aux_lock")
Fixes: 63b85ac56a64 ("kasan: stop leaking stack trace handles")
Fixes: 08d7c94d9635 ("kasan: memset free track in qlink_free")
Fixes: a414d4286f34 ("kasan: handle concurrent kasan_record_aux_stack calls")
Fixes: 773688a6cb24 ("kasan: use stack_depot_put for Generic mode")
Signed-off-by: Marco Elver &lt;elver@google.com&gt;
Reviewed-by: Andrey Konovalov &lt;andreyknvl@gmail.com&gt;
Tested-by: Mikhail Gavrilov &lt;mikhail.v.gavrilov@gmail.com&gt;
Cc: Alexander Potapenko &lt;glider@google.com&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Andrey Ryabinin &lt;ryabinin.a.a@gmail.com&gt;
Cc: Vincenzo Frascino &lt;vincenzo.frascino@arm.com&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'mm-stable-2024-01-08-15-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2024-01-09T19:18:47+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-01-09T19:18:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=fb46e22a9e3863e08aef8815df9f17d0f4b9aede'/>
<id>urn:sha1:fb46e22a9e3863e08aef8815df9f17d0f4b9aede</id>
<content type='text'>
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:

   - Peng Zhang has done some mapletree maintainance work in the series

	'maple_tree: add mt_free_one() and mt_attr() helpers'
	'Some cleanups of maple tree'

   - In the series 'mm: use memmap_on_memory semantics for dax/kmem'
     Vishal Verma has altered the interworking between memory-hotplug
     and dax/kmem so that newly added 'device memory' can more easily
     have its memmap placed within that newly added memory.

   - Matthew Wilcox continues folio-related work (including a few fixes)
     in the patch series

	'Add folio_zero_tail() and folio_fill_tail()'
	'Make folio_start_writeback return void'
	'Fix fault handler's handling of poisoned tail pages'
	'Convert aops-&gt;error_remove_page to -&gt;error_remove_folio'
	'Finish two folio conversions'
	'More swap folio conversions'

   - Kefeng Wang has also contributed folio-related work in the series

	'mm: cleanup and use more folio in page fault'

   - Jim Cromie has improved the kmemleak reporting output in the series
     'tweak kmemleak report format'.

   - In the series 'stackdepot: allow evicting stack traces' Andrey
     Konovalov to permits clients (in this case KASAN) to cause eviction
     of no longer needed stack traces.

   - Charan Teja Kalla has fixed some accounting issues in the page
     allocator's atomic reserve calculations in the series 'mm:
     page_alloc: fixes for high atomic reserve caluculations'.

   - Dmitry Rokosov has added to the samples/ dorectory some sample code
     for a userspace memcg event listener application. See the series
     'samples: introduce cgroup events listeners'.

   - Some mapletree maintanance work from Liam Howlett in the series
     'maple_tree: iterator state changes'.

   - Nhat Pham has improved zswap's approach to writeback in the series
     'workload-specific and memory pressure-driven zswap writeback'.

   - DAMON/DAMOS feature and maintenance work from SeongJae Park in the
     series

	'mm/damon: let users feed and tame/auto-tune DAMOS'
	'selftests/damon: add Python-written DAMON functionality tests'
	'mm/damon: misc updates for 6.8'

   - Yosry Ahmed has improved memcg's stats flushing in the series 'mm:
     memcg: subtree stats flushing and thresholds'.

   - In the series 'Multi-size THP for anonymous memory' Ryan Roberts
     has added a runtime opt-in feature to transparent hugepages which
     improves performance by allocating larger chunks of memory during
     anonymous page faults.

   - Matthew Wilcox has also contributed some cleanup and maintenance
     work against eh buffer_head code int he series 'More buffer_head
     cleanups'.

   - Suren Baghdasaryan has done work on Andrea Arcangeli's series
     'userfaultfd move option'. UFFDIO_MOVE permits userspace heap
     compaction algorithms to move userspace's pages around rather than
     UFFDIO_COPY'a alloc/copy/free.

   - Stefan Roesch has developed a 'KSM Advisor', in the series 'mm/ksm:
     Add ksm advisor'. This is a governor which tunes KSM's scanning
     aggressiveness in response to userspace's current needs.

   - Chengming Zhou has optimized zswap's temporary working memory use
     in the series 'mm/zswap: dstmem reuse optimizations and cleanups'.

   - Matthew Wilcox has performed some maintenance work on the writeback
     code, both code and within filesystems. The series is 'Clean up the
     writeback paths'.

   - Andrey Konovalov has optimized KASAN's handling of alloc and free
     stack traces for secondary-level allocators, in the series 'kasan:
     save mempool stack traces'.

   - Andrey also performed some KASAN maintenance work in the series
     'kasan: assorted clean-ups'.

   - David Hildenbrand has gone to town on the rmap code. Cleanups, more
     pte batching, folio conversions and more. See the series 'mm/rmap:
     interface overhaul'.

   - Kinsey Ho has contributed some maintenance work on the MGLRU code
     in the series 'mm/mglru: Kconfig cleanup'.

   - Matthew Wilcox has contributed lruvec page accounting code cleanups
     in the series 'Remove some lruvec page accounting functions'"

* tag 'mm-stable-2024-01-08-15-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (361 commits)
  mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER
  mm, treewide: introduce NR_PAGE_ORDERS
  selftests/mm: add separate UFFDIO_MOVE test for PMD splitting
  selftests/mm: skip test if application doesn't has root privileges
  selftests/mm: conform test to TAP format output
  selftests: mm: hugepage-mmap: conform to TAP format output
  selftests/mm: gup_test: conform test to TAP format output
  mm/selftests: hugepage-mremap: conform test to TAP format output
  mm/vmstat: move pgdemote_* out of CONFIG_NUMA_BALANCING
  mm: zsmalloc: return -ENOSPC rather than -EINVAL in zs_malloc while size is too large
  mm/memcontrol: remove __mod_lruvec_page_state()
  mm/khugepaged: use a folio more in collapse_file()
  slub: use a folio in __kmalloc_large_node
  slub: use folio APIs in free_large_kmalloc()
  slub: use alloc_pages_node() in alloc_slab_page()
  mm: remove inc/dec lruvec page state functions
  mm: ratelimit stat flush from workingset shrinker
  kasan: stop leaking stack trace handles
  mm/mglru: remove CONFIG_TRANSPARENT_HUGEPAGE
  mm/mglru: add dummy pmd_dirty()
  ...
</content>
</entry>
<entry>
<title>kasan: stop leaking stack trace handles</title>
<updated>2024-01-05T18:17:45+00:00</updated>
<author>
<name>Andrey Konovalov</name>
<email>andreyknvl@google.com</email>
</author>
<published>2023-12-26T22:51:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=63b85ac56a6498476fb34402c10a3f431f62f35c'/>
<id>urn:sha1:63b85ac56a6498476fb34402c10a3f431f62f35c</id>
<content type='text'>
Commit 773688a6cb24 ("kasan: use stack_depot_put for Generic mode") added
support for stack trace eviction for Generic KASAN.

However, that commit didn't evict stack traces when the object is not put
into quarantine.  As a result, some stack traces are never evicted from
the stack depot.

In addition, with the "kasan: save mempool stack traces" series, the free
stack traces for mempool objects are also not properly evicted from the
stack depot.

Fix both issues by:

1. Evicting all stack traces when an object if freed if it was not put
   into quarantine;

2. Always evicting an existing free stack trace when a new one is saved.

Also do a few related clean-ups:

- Do not zero out free track when initializing/invalidating free meta:
  set a value in shadow memory instead;

- Rename KASAN_SLAB_FREETRACK to KASAN_SLAB_FREE_META;

- Drop the kasan_init_cache_meta function as it's not used by KASAN;

- Add comments for the kasan_alloc_meta and kasan_free_meta structs.

[akpm@linux-foundation.org: make release_free_meta() and release_alloc_meta() static]
Link: https://lkml.kernel.org/r/20231226225121.235865-1-andrey.konovalov@linux.dev
Fixes: 773688a6cb24 ("kasan: use stack_depot_put for Generic mode")
Signed-off-by: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Cc: Alexander Potapenko &lt;glider@google.com&gt;
Cc: Andrey Ryabinin &lt;ryabinin.a.a@gmail.com&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Marco Elver &lt;elver@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>kasan: memset free track in qlink_free</title>
<updated>2023-12-29T19:58:42+00:00</updated>
<author>
<name>Andrey Konovalov</name>
<email>andreyknvl@google.com</email>
</author>
<published>2023-12-19T21:19:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=08d7c94d9635cf3fdffcab5f066d857efbad9507'/>
<id>urn:sha1:08d7c94d9635cf3fdffcab5f066d857efbad9507</id>
<content type='text'>
Instead of only zeroing out the stack depot handle when evicting the
free stack trace in qlink_free, zero out the whole track.

Do this just to produce a similar effect for alloc and free meta. The
other fields of the free track besides the stack trace handle are
considered invalid at this point anyway, so no harm in zeroing them out.

Link: https://lkml.kernel.org/r/db987c1cd011547e85353b0b9997de190c97e3e6.1703020707.git.andreyknvl@google.com
Fixes: 773688a6cb24 ("kasan: use stack_depot_put for Generic mode")
Signed-off-by: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Reviewed-by: Marco Elver &lt;elver@google.com&gt;
Cc: Alexander Potapenko &lt;glider@google.com&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Evgenii Stepanov &lt;eugenis@google.com&gt;
Cc: Tetsuo Handa &lt;penguin-kernel@i-love.sakura.ne.jp&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>kasan: use stack_depot_put for Generic mode</title>
<updated>2023-12-11T00:51:48+00:00</updated>
<author>
<name>Andrey Konovalov</name>
<email>andreyknvl@google.com</email>
</author>
<published>2023-11-20T17:47:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=773688a6cb24b0b3c2ba40354d883348a2befa38'/>
<id>urn:sha1:773688a6cb24b0b3c2ba40354d883348a2befa38</id>
<content type='text'>
Evict alloc/free stack traces from the stack depot for Generic KASAN once
they are evicted from the quaratine.

For auxiliary stack traces, evict the oldest stack trace once a new one is
saved (KASAN only keeps references to the last two).

Also evict all saved stack traces on krealloc.

To avoid double-evicting and mis-evicting stack traces (in case KASAN's
metadata was corrupted), reset KASAN's per-object metadata that stores
stack depot handles when the object is initialized and when it's evicted
from the quarantine.

Note that stack_depot_put is no-op if the handle is 0.

Link: https://lkml.kernel.org/r/5cef104d9b842899489b4054fe8d1339a71acee0.1700502145.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Reviewed-by: Marco Elver &lt;elver@google.com&gt;
Cc: Alexander Potapenko &lt;glider@google.com&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Evgenii Stepanov &lt;eugenis@google.com&gt;
Cc: Oscar Salvador &lt;osalvador@suse.de&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>KASAN: remove code paths guarded by CONFIG_SLAB</title>
<updated>2023-12-05T10:17:51+00:00</updated>
<author>
<name>Vlastimil Babka</name>
<email>vbabka@suse.cz</email>
</author>
<published>2023-10-02T14:17:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=72786c0a3dc5d4151469f512909049a0b17ada3d'/>
<id>urn:sha1:72786c0a3dc5d4151469f512909049a0b17ada3d</id>
<content type='text'>
With SLAB removed and SLUB the only remaining allocator, we can clean up
some code that was depending on the choice.

Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Marco Elver &lt;elver@google.com&gt;
Reviewed-by: Andrey Konovalov &lt;andreyknvl@gmail.com&gt;
Acked-by: David Rientjes &lt;rientjes@google.com&gt;
Tested-by: David Rientjes &lt;rientjes@google.com&gt;
Reviewed-by: Hyeonggon Yoo &lt;42.hyeyoo@gmail.com&gt;
Tested-by: Hyeonggon Yoo &lt;42.hyeyoo@gmail.com&gt;
Signed-off-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
</content>
</entry>
<entry>
<title>kasan: unify printk prefixes</title>
<updated>2023-10-18T21:34:15+00:00</updated>
<author>
<name>Andrey Konovalov</name>
<email>andreyknvl@google.com</email>
</author>
<published>2023-10-06T15:18:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=d7196d87a1559db9ece24852e6167061b199d58d'/>
<id>urn:sha1:d7196d87a1559db9ece24852e6167061b199d58d</id>
<content type='text'>
Unify prefixes for printk messages in mm/kasan/.

Link: https://lkml.kernel.org/r/35589629806cf0840e5f01ec9d8011a7bad648df.1696605143.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Reviewed-by: Marco Elver &lt;elver@google.com&gt;
Cc: Alexander Potapenko &lt;glider@google.com&gt;
Cc: Andrey Ryabinin &lt;ryabinin.a.a@gmail.com&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>kasan: fix lockdep report invalid wait context</title>
<updated>2023-04-21T21:51:59+00:00</updated>
<author>
<name>Zqiang</name>
<email>qiang1.zhang@intel.com</email>
</author>
<published>2023-03-27T12:00:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=be41d814c6c7bbf3ffa66faeefa01f6cea8e3c98'/>
<id>urn:sha1:be41d814c6c7bbf3ffa66faeefa01f6cea8e3c98</id>
<content type='text'>
For kernels built with the following options and booting

CONFIG_SLUB=y
CONFIG_DEBUG_LOCKDEP=y
CONFIG_PROVE_LOCKING=y
CONFIG_PROVE_RAW_LOCK_NESTING=y

[    0.523115] [ BUG: Invalid wait context ]
[    0.523315] 6.3.0-rc1-yocto-standard+ #739 Not tainted
[    0.523649] -----------------------------
[    0.523663] swapper/0/0 is trying to lock:
[    0.523663] ffff888035611360 (&amp;c-&gt;lock){....}-{3:3}, at: put_cpu_partial+0x2e/0x1e0
[    0.523663] other info that might help us debug this:
[    0.523663] context-{2:2}
[    0.523663] no locks held by swapper/0/0.
[    0.523663] stack backtrace:
[    0.523663] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.3.0-rc1-yocto-standard+ #739
[    0.523663] Call Trace:
[    0.523663]  &lt;IRQ&gt;
[    0.523663]  dump_stack_lvl+0x64/0xb0
[    0.523663]  dump_stack+0x10/0x20
[    0.523663]  __lock_acquire+0x6c4/0x3c10
[    0.523663]  lock_acquire+0x188/0x460
[    0.523663]  put_cpu_partial+0x5a/0x1e0
[    0.523663]  __slab_free+0x39a/0x520
[    0.523663]  ___cache_free+0xa9/0xc0
[    0.523663]  qlist_free_all+0x7a/0x160
[    0.523663]  per_cpu_remove_cache+0x5c/0x70
[    0.523663]  __flush_smp_call_function_queue+0xfc/0x330
[    0.523663]  generic_smp_call_function_single_interrupt+0x13/0x20
[    0.523663]  __sysvec_call_function+0x86/0x2e0
[    0.523663]  sysvec_call_function+0x73/0x90
[    0.523663]  &lt;/IRQ&gt;
[    0.523663]  &lt;TASK&gt;
[    0.523663]  asm_sysvec_call_function+0x1b/0x20
[    0.523663] RIP: 0010:default_idle+0x13/0x20
[    0.523663] RSP: 0000:ffffffff83e07dc0 EFLAGS: 00000246
[    0.523663] RAX: 0000000000000000 RBX: ffffffff83e1e200 RCX: ffffffff82a83293
[    0.523663] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8119a6b1
[    0.523663] RBP: ffffffff83e07dc8 R08: 0000000000000001 R09: ffffed1006ac0d66
[    0.523663] R10: ffff888035606b2b R11: ffffed1006ac0d65 R12: 0000000000000000
[    0.523663] R13: ffffffff83e1e200 R14: ffffffff84a7d980 R15: 0000000000000000
[    0.523663]  default_idle_call+0x6c/0xa0
[    0.523663]  do_idle+0x2e1/0x330
[    0.523663]  cpu_startup_entry+0x20/0x30
[    0.523663]  rest_init+0x152/0x240
[    0.523663]  arch_call_rest_init+0x13/0x40
[    0.523663]  start_kernel+0x331/0x470
[    0.523663]  x86_64_start_reservations+0x18/0x40
[    0.523663]  x86_64_start_kernel+0xbb/0x120
[    0.523663]  secondary_startup_64_no_verify+0xe0/0xeb
[    0.523663]  &lt;/TASK&gt;

The local_lock_irqsave() is invoked in put_cpu_partial() and happens in
IPI context, due to the CONFIG_PROVE_RAW_LOCK_NESTING=y (the
LD_WAIT_CONFIG not equal to LD_WAIT_SPIN), so acquire local_lock in IPI
context will trigger above calltrace.

This commit therefore moves qlist_free_all() from hard-irq context to task
context.

Link: https://lkml.kernel.org/r/20230327120019.1027640-1-qiang1.zhang@intel.com
Signed-off-by: Zqiang &lt;qiang1.zhang@intel.com&gt;
Acked-by: Marco Elver &lt;elver@google.com&gt;
Cc: Alexander Potapenko &lt;glider@google.com&gt;
Cc: Andrey Konovalov &lt;andreyknvl@gmail.com&gt;
Cc: Andrey Ryabinin &lt;ryabinin.a.a@gmail.com&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>kasan: give better names to shadow values</title>
<updated>2022-05-13T14:20:19+00:00</updated>
<author>
<name>Andrey Konovalov</name>
<email>andreyknvl@google.com</email>
</author>
<published>2022-05-13T03:23:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=06bc4cf6cdde69079c82330aa8f0939d680b6c84'/>
<id>urn:sha1:06bc4cf6cdde69079c82330aa8f0939d680b6c84</id>
<content type='text'>
Rename KASAN_KMALLOC_* shadow values to KASAN_SLAB_*, as they are used for
all slab allocations, not only for kmalloc.

Also rename KASAN_FREE_PAGE to KASAN_PAGE_FREE to be consistent with
KASAN_PAGE_REDZONE and KASAN_SLAB_FREE.

Link: https://lkml.kernel.org/r/bebcaf4eafdb0cabae0401a69c0af956aa87fcaa.1652111464.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Reviewed-by: Alexander Potapenko &lt;glider@google.com&gt;
Cc: Andrey Ryabinin &lt;ryabinin.a.a@gmail.com&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Marco Elver &lt;elver@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>kasan: fix sleeping function called from invalid context on RT kernel</title>
<updated>2022-04-29T21:36:58+00:00</updated>
<author>
<name>Zqiang</name>
<email>qiang1.zhang@intel.com</email>
</author>
<published>2022-04-29T21:36:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=07d067e4f2ceb72b9f681995cc53828caaba9e6e'/>
<id>urn:sha1:07d067e4f2ceb72b9f681995cc53828caaba9e6e</id>
<content type='text'>
BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 1, name: swapper/0
preempt_count: 1, expected: 0
...........
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.17.1-rt16-yocto-preempt-rt #22
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009),
BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014
Call Trace:
&lt;TASK&gt;
dump_stack_lvl+0x60/0x8c
dump_stack+0x10/0x12
 __might_resched.cold+0x13b/0x173
rt_spin_lock+0x5b/0xf0
 ___cache_free+0xa5/0x180
qlist_free_all+0x7a/0x160
per_cpu_remove_cache+0x5f/0x70
smp_call_function_many_cond+0x4c4/0x4f0
on_each_cpu_cond_mask+0x49/0xc0
kasan_quarantine_remove_cache+0x54/0xf0
kasan_cache_shrink+0x9/0x10
kmem_cache_shrink+0x13/0x20
acpi_os_purge_cache+0xe/0x20
acpi_purge_cached_objects+0x21/0x6d
acpi_initialize_objects+0x15/0x3b
acpi_init+0x130/0x5ba
do_one_initcall+0xe5/0x5b0
kernel_init_freeable+0x34f/0x3ad
kernel_init+0x1e/0x140
ret_from_fork+0x22/0x30

When the kmem_cache_shrink() was called, the IPI was triggered, the
___cache_free() is called in IPI interrupt context, the local-lock or
spin-lock will be acquired.  On PREEMPT_RT kernel, these locks are
replaced with sleepbale rt-spinlock, so the above problem is triggered. 
Fix it by moving the qlist_free_allfrom() from IPI interrupt context to
task context when PREEMPT_RT is enabled.

[akpm@linux-foundation.org: reduce ifdeffery]
Link: https://lkml.kernel.org/r/20220401134649.2222485-1-qiang1.zhang@intel.com
Signed-off-by: Zqiang &lt;qiang1.zhang@intel.com&gt;
Acked-by: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Andrey Ryabinin &lt;ryabinin.a.a@gmail.com&gt;
Cc: Alexander Potapenko &lt;glider@google.com&gt;
Cc: Andrey Konovalov &lt;andreyknvl@gmail.com&gt;
Cc: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
</feed>
