<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/lib, branch v6.12.64</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>idr: fix idr_alloc() returning an ID out of range</title>
<updated>2026-01-08T09:14:50+00:00</updated>
<author>
<name>Matthew Wilcox (Oracle)</name>
<email>willy@infradead.org</email>
</author>
<published>2025-11-28T16:18:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=36cdde5c28c9a1597d444feb9e95d174a2923e29'/>
<id>36cdde5c28c9a1597d444feb9e95d174a2923e29</id>
<content type='text'>
commit c6e8e595a0798ad67da0f7bebaf69c31ef70dfff upstream.

If you use an IDR with a non-zero base, and specify a range that lies
entirely below the base, 'max - base' becomes very large and
idr_get_free() can return an ID that lies outside of the requested range.

Link: https://lkml.kernel.org/r/20251128161853.3200058-1-willy@infradead.org
Fixes: 6ce711f27500 ("idr: Make 1-based IDRs more efficient")
Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Reported-by: Jan Sokolowski &lt;jan.sokolowski@intel.com&gt;
Reported-by: Koen Koning &lt;koen.koning@intel.com&gt;
Reported-by: Peter Senna Tschudin &lt;peter.senna@linux.intel.com&gt;
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6449
Reviewed-by: Christian König &lt;christian.koenig@amd.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit c6e8e595a0798ad67da0f7bebaf69c31ef70dfff upstream.

If you use an IDR with a non-zero base, and specify a range that lies
entirely below the base, 'max - base' becomes very large and
idr_get_free() can return an ID that lies outside of the requested range.

Link: https://lkml.kernel.org/r/20251128161853.3200058-1-willy@infradead.org
Fixes: 6ce711f27500 ("idr: Make 1-based IDRs more efficient")
Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Reported-by: Jan Sokolowski &lt;jan.sokolowski@intel.com&gt;
Reported-by: Koen Koning &lt;koen.koning@intel.com&gt;
Reported-by: Peter Senna Tschudin &lt;peter.senna@linux.intel.com&gt;
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6449
Reviewed-by: Christian König &lt;christian.koenig@amd.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>lib/vsprintf: Check pointer before dereferencing in time_and_date()</title>
<updated>2025-12-18T12:54:57+00:00</updated>
<author>
<name>Andy Shevchenko</name>
<email>andriy.shevchenko@linux.intel.com</email>
</author>
<published>2025-11-10T13:21:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c2a0862ad4c368ffd40a0dcdd4b571f63c274876'/>
<id>c2a0862ad4c368ffd40a0dcdd4b571f63c274876</id>
<content type='text'>
[ Upstream commit 372a12bd5df0199aa234eaf8ef31ed7ecd61d40f ]

The pointer may be invalid when gets to the printf(). In particular
the time_and_date() dereferencing it in some cases without checking.

Move the check from rtc_str() to time_and_date() to cover all cases.

Fixes: 7daac5b2fdf8 ("lib/vsprintf: Print time64_t in human readable format")
Signed-off-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Reviewed-by: Petr Mladek &lt;pmladek@suse.com&gt;
Link: https://patch.msgid.link/20251110132118.4113976-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Petr Mladek &lt;pmladek@suse.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 372a12bd5df0199aa234eaf8ef31ed7ecd61d40f ]

The pointer may be invalid when gets to the printf(). In particular
the time_and_date() dereferencing it in some cases without checking.

Move the check from rtc_str() to time_and_date() to cover all cases.

Fixes: 7daac5b2fdf8 ("lib/vsprintf: Print time64_t in human readable format")
Signed-off-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Reviewed-by: Petr Mladek &lt;pmladek@suse.com&gt;
Link: https://patch.msgid.link/20251110132118.4113976-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Petr Mladek &lt;pmladek@suse.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>maple_tree: fix tracepoint string pointers</title>
<updated>2025-12-01T10:43:39+00:00</updated>
<author>
<name>Martin Kaiser</name>
<email>martin@kaiser.cx</email>
</author>
<published>2025-10-30T15:55:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4ade59d68a0aea0d94a72d9e5bb4fa5fa2ad478c'/>
<id>4ade59d68a0aea0d94a72d9e5bb4fa5fa2ad478c</id>
<content type='text'>
commit 91a54090026f84ceffaa12ac53c99b9f162946f6 upstream.

maple_tree tracepoints contain pointers to function names. Such a pointer
is saved when a tracepoint logs an event. There's no guarantee that it's
still valid when the event is parsed later and the pointer is dereferenced.

The kernel warns about these unsafe pointers.

	event 'ma_read' has unsafe pointer field 'fn'
	WARNING: kernel/trace/trace.c:3779 at ignore_event+0x1da/0x1e4

Mark the function names as tracepoint_string() to fix the events.

One case that doesn't work without my patch would be trace-cmd record
to save the binary ringbuffer and trace-cmd report to parse it in
userspace.  The address of __func__ can't be dereferenced from
userspace but tracepoint_string will add an entry to
/sys/kernel/tracing/printk_formats

Link: https://lkml.kernel.org/r/20251030155537.87972-1-martin@kaiser.cx
Fixes: 54a611b60590 ("Maple Tree: add new data structure")
Signed-off-by: Martin Kaiser &lt;martin@kaiser.cx&gt;
Acked-by: Liam R. Howlett &lt;Liam.Howlett@oracle.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 91a54090026f84ceffaa12ac53c99b9f162946f6 upstream.

maple_tree tracepoints contain pointers to function names. Such a pointer
is saved when a tracepoint logs an event. There's no guarantee that it's
still valid when the event is parsed later and the pointer is dereferenced.

The kernel warns about these unsafe pointers.

	event 'ma_read' has unsafe pointer field 'fn'
	WARNING: kernel/trace/trace.c:3779 at ignore_event+0x1da/0x1e4

Mark the function names as tracepoint_string() to fix the events.

One case that doesn't work without my patch would be trace-cmd record
to save the binary ringbuffer and trace-cmd report to parse it in
userspace.  The address of __func__ can't be dereferenced from
userspace but tracepoint_string will add an entry to
/sys/kernel/tracing/printk_formats

Link: https://lkml.kernel.org/r/20251030155537.87972-1-martin@kaiser.cx
Fixes: 54a611b60590 ("Maple Tree: add new data structure")
Signed-off-by: Martin Kaiser &lt;martin@kaiser.cx&gt;
Acked-by: Liam R. Howlett &lt;Liam.Howlett@oracle.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>lib/crypto: curve25519-hacl64: Fix older clang KASAN workaround for GCC</title>
<updated>2025-11-13T20:34:40+00:00</updated>
<author>
<name>Nathan Chancellor</name>
<email>nathan@kernel.org</email>
</author>
<published>2025-11-03T19:11:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c664eb11660399753ad076c46a05399c3d2b719c'/>
<id>c664eb11660399753ad076c46a05399c3d2b719c</id>
<content type='text'>
commit 2b81082ad37cc3f28355fb73a6a69b91ff7dbf20 upstream.

Commit 2f13daee2a72 ("lib/crypto/curve25519-hacl64: Disable KASAN with
clang-17 and older") inadvertently disabled KASAN in curve25519-hacl64.o
for GCC unconditionally because clang-min-version will always evaluate
to nothing for GCC. Add a check for CONFIG_CC_IS_CLANG to avoid applying
the workaround for GCC, which is only needed for clang-17 and older.

Cc: stable@vger.kernel.org
Fixes: 2f13daee2a72 ("lib/crypto/curve25519-hacl64: Disable KASAN with clang-17 and older")
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Acked-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Link: https://lore.kernel.org/r/20251103-curve25519-hacl64-fix-kasan-workaround-v2-1-ab581cbd8035@kernel.org
Signed-off-by: Eric Biggers &lt;ebiggers@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 2b81082ad37cc3f28355fb73a6a69b91ff7dbf20 upstream.

Commit 2f13daee2a72 ("lib/crypto/curve25519-hacl64: Disable KASAN with
clang-17 and older") inadvertently disabled KASAN in curve25519-hacl64.o
for GCC unconditionally because clang-min-version will always evaluate
to nothing for GCC. Add a check for CONFIG_CC_IS_CLANG to avoid applying
the workaround for GCC, which is only needed for clang-17 and older.

Cc: stable@vger.kernel.org
Fixes: 2f13daee2a72 ("lib/crypto/curve25519-hacl64: Disable KASAN with clang-17 and older")
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Acked-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Link: https://lore.kernel.org/r/20251103-curve25519-hacl64-fix-kasan-workaround-v2-1-ab581cbd8035@kernel.org
Signed-off-by: Eric Biggers &lt;ebiggers@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>kunit: test_dev_action: Correctly cast 'priv' pointer to long*</title>
<updated>2025-11-13T20:33:57+00:00</updated>
<author>
<name>Florian Schmaus</name>
<email>florian.schmaus@codasip.com</email>
</author>
<published>2025-10-17T09:28:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=22aa7d1631e8a7acbd921aee707576ae8c579edd'/>
<id>22aa7d1631e8a7acbd921aee707576ae8c579edd</id>
<content type='text'>
[ Upstream commit 2551a1eedc09f5a86f94b038dc1bb16855c256f1 ]

The previous implementation incorrectly assumed the original type of
'priv' was void**, leading to an unnecessary and misleading
cast. Correct the cast of the 'priv' pointer in test_dev_action() to
its actual type, long*, removing an unnecessary cast.

As an additional benefit, this fixes an out-of-bounds CHERI fault on
hardware with architectural capabilities. The original implementation
tried to store a capability-sized pointer using the priv
pointer. However, the priv pointer's capability only granted access to
the memory region of its original long type, leading to a bounds
violation since the size of a long is smaller than the size of a
capability. This change ensures that the pointer usage respects the
capabilities' bounds.

Link: https://lore.kernel.org/r/20251017092814.80022-1-florian.schmaus@codasip.com
Fixes: d03c720e03bd ("kunit: Add APIs for managing devices")
Reviewed-by: David Gow &lt;davidgow@google.com&gt;
Signed-off-by: Florian Schmaus &lt;florian.schmaus@codasip.com&gt;
Signed-off-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 2551a1eedc09f5a86f94b038dc1bb16855c256f1 ]

The previous implementation incorrectly assumed the original type of
'priv' was void**, leading to an unnecessary and misleading
cast. Correct the cast of the 'priv' pointer in test_dev_action() to
its actual type, long*, removing an unnecessary cast.

As an additional benefit, this fixes an out-of-bounds CHERI fault on
hardware with architectural capabilities. The original implementation
tried to store a capability-sized pointer using the priv
pointer. However, the priv pointer's capability only granted access to
the memory region of its original long type, leading to a bounds
violation since the size of a long is smaller than the size of a
capability. This change ensures that the pointer usage respects the
capabilities' bounds.

Link: https://lore.kernel.org/r/20251017092814.80022-1-florian.schmaus@codasip.com
Fixes: d03c720e03bd ("kunit: Add APIs for managing devices")
Reviewed-by: David Gow &lt;davidgow@google.com&gt;
Signed-off-by: Florian Schmaus &lt;florian.schmaus@codasip.com&gt;
Signed-off-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>lib/crypto/curve25519-hacl64: Disable KASAN with clang-17 and older</title>
<updated>2025-10-19T14:34:00+00:00</updated>
<author>
<name>Nathan Chancellor</name>
<email>nathan@kernel.org</email>
</author>
<published>2025-06-09T22:45:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6f02e337cbf4c78755cae9614df040cb57ccfd0a'/>
<id>6f02e337cbf4c78755cae9614df040cb57ccfd0a</id>
<content type='text'>
commit 2f13daee2a72bb962f5fd356c3a263a6f16da965 upstream.

After commit 6f110a5e4f99 ("Disable SLUB_TINY for build testing"), which
causes CONFIG_KASAN to be enabled in allmodconfig again, arm64
allmodconfig builds with clang-17 and older show an instance of
-Wframe-larger-than (which breaks the build with CONFIG_WERROR=y):

  lib/crypto/curve25519-hacl64.c:757:6: error: stack frame size (2336) exceeds limit (2048) in 'curve25519_generic' [-Werror,-Wframe-larger-than]
    757 | void curve25519_generic(u8 mypublic[CURVE25519_KEY_SIZE],
        |      ^

When KASAN is disabled, the stack usage is roughly quartered:

  lib/crypto/curve25519-hacl64.c:757:6: error: stack frame size (608) exceeds limit (128) in 'curve25519_generic' [-Werror,-Wframe-larger-than]
    757 | void curve25519_generic(u8 mypublic[CURVE25519_KEY_SIZE],
        |      ^

Using '-Rpass-analysis=stack-frame-layout' shows the following variables
and many, many 8-byte spills when KASAN is enabled:

  Offset: [SP-144], Type: Variable, Align: 8, Size: 40
  Offset: [SP-464], Type: Variable, Align: 8, Size: 320
  Offset: [SP-784], Type: Variable, Align: 8, Size: 320
  Offset: [SP-864], Type: Variable, Align: 32, Size: 80
  Offset: [SP-896], Type: Variable, Align: 32, Size: 32
  Offset: [SP-1016], Type: Variable, Align: 8, Size: 120

When KASAN is disabled, there are still spills but not at many and the
variables list is smaller:

  Offset: [SP-192], Type: Variable, Align: 32, Size: 80
  Offset: [SP-224], Type: Variable, Align: 32, Size: 32
  Offset: [SP-344], Type: Variable, Align: 8, Size: 120

Disable KASAN for this file when using clang-17 or older to avoid
blowing out the stack, clearing up the warning.

Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Acked-by: "Jason A. Donenfeld" &lt;Jason@zx2c4.com&gt;
Acked-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Link: https://lore.kernel.org/r/20250609-curve25519-hacl64-disable-kasan-clang-v1-1-08ea0ac5ccff@kernel.org
Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 2f13daee2a72bb962f5fd356c3a263a6f16da965 upstream.

After commit 6f110a5e4f99 ("Disable SLUB_TINY for build testing"), which
causes CONFIG_KASAN to be enabled in allmodconfig again, arm64
allmodconfig builds with clang-17 and older show an instance of
-Wframe-larger-than (which breaks the build with CONFIG_WERROR=y):

  lib/crypto/curve25519-hacl64.c:757:6: error: stack frame size (2336) exceeds limit (2048) in 'curve25519_generic' [-Werror,-Wframe-larger-than]
    757 | void curve25519_generic(u8 mypublic[CURVE25519_KEY_SIZE],
        |      ^

When KASAN is disabled, the stack usage is roughly quartered:

  lib/crypto/curve25519-hacl64.c:757:6: error: stack frame size (608) exceeds limit (128) in 'curve25519_generic' [-Werror,-Wframe-larger-than]
    757 | void curve25519_generic(u8 mypublic[CURVE25519_KEY_SIZE],
        |      ^

Using '-Rpass-analysis=stack-frame-layout' shows the following variables
and many, many 8-byte spills when KASAN is enabled:

  Offset: [SP-144], Type: Variable, Align: 8, Size: 40
  Offset: [SP-464], Type: Variable, Align: 8, Size: 320
  Offset: [SP-784], Type: Variable, Align: 8, Size: 320
  Offset: [SP-864], Type: Variable, Align: 32, Size: 80
  Offset: [SP-896], Type: Variable, Align: 32, Size: 32
  Offset: [SP-1016], Type: Variable, Align: 8, Size: 120

When KASAN is disabled, there are still spills but not at many and the
variables list is smaller:

  Offset: [SP-192], Type: Variable, Align: 32, Size: 80
  Offset: [SP-224], Type: Variable, Align: 32, Size: 32
  Offset: [SP-344], Type: Variable, Align: 8, Size: 120

Disable KASAN for this file when using clang-17 or older to avoid
blowing out the stack, clearing up the warning.

Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Acked-by: "Jason A. Donenfeld" &lt;Jason@zx2c4.com&gt;
Acked-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Link: https://lore.kernel.org/r/20250609-curve25519-hacl64-disable-kasan-clang-v1-1-08ea0ac5ccff@kernel.org
Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>lib/genalloc: fix device leak in of_gen_pool_get()</title>
<updated>2025-10-19T14:33:51+00:00</updated>
<author>
<name>Johan Hovold</name>
<email>johan@kernel.org</email>
</author>
<published>2025-09-24T08:02:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e5400e8272208ffce4fad4b1cdd7fb7ad5475cb2'/>
<id>e5400e8272208ffce4fad4b1cdd7fb7ad5475cb2</id>
<content type='text'>
commit 1260cbcffa608219fc9188a6cbe9c45a300ef8b5 upstream.

Make sure to drop the reference taken when looking up the genpool platform
device in of_gen_pool_get() before returning the pool.

Note that holding a reference to a device does typically not prevent its
devres managed resources from being released so there is no point in
keeping the reference.

Link: https://lkml.kernel.org/r/20250924080207.18006-1-johan@kernel.org
Fixes: 9375db07adea ("genalloc: add devres support, allow to find a managed pool by device")
Signed-off-by: Johan Hovold &lt;johan@kernel.org&gt;
Cc: Philipp Zabel &lt;p.zabel@pengutronix.de&gt;
Cc: Vladimir Zapolskiy &lt;vz@mleia.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;	[3.10+]
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 1260cbcffa608219fc9188a6cbe9c45a300ef8b5 upstream.

Make sure to drop the reference taken when looking up the genpool platform
device in of_gen_pool_get() before returning the pool.

Note that holding a reference to a device does typically not prevent its
devres managed resources from being released so there is no point in
keeping the reference.

Link: https://lkml.kernel.org/r/20250924080207.18006-1-johan@kernel.org
Fixes: 9375db07adea ("genalloc: add devres support, allow to find a managed pool by device")
Signed-off-by: Johan Hovold &lt;johan@kernel.org&gt;
Cc: Philipp Zabel &lt;p.zabel@pengutronix.de&gt;
Cc: Vladimir Zapolskiy &lt;vz@mleia.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;	[3.10+]
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>lib/sbitmap: convert shallow_depth from one word to the whole sbitmap</title>
<updated>2025-08-20T16:30:49+00:00</updated>
<author>
<name>Yu Kuai</name>
<email>yukuai3@huawei.com</email>
</author>
<published>2025-08-07T03:24:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ed30c38d1e002916b7ef816ba2a56f621a85ed00'/>
<id>ed30c38d1e002916b7ef816ba2a56f621a85ed00</id>
<content type='text'>
[ Upstream commit 42e6c6ce03fd3e41e39a0f93f9b1a1d9fa664338 ]

Currently elevators will record internal 'async_depth' to throttle
asynchronous requests, and they both calculate shallow_dpeth based on
sb-&gt;shift, with the respect that sb-&gt;shift is the available tags in one
word.

However, sb-&gt;shift is not the availbale tags in the last word, see
__map_depth:

if (index == sb-&gt;map_nr - 1)
  return sb-&gt;depth - (index &lt;&lt; sb-&gt;shift);

For consequence, if the last word is used, more tags can be get than
expected, for example, assume nr_requests=256 and there are four words,
in the worst case if user set nr_requests=32, then the first word is
the last word, and still use bits per word, which is 64, to calculate
async_depth is wrong.

One the ohter hand, due to cgroup qos, bfq can allow only one request
to be allocated, and set shallow_dpeth=1 will still allow the number
of words request to be allocated.

Fix this problems by using shallow_depth to the whole sbitmap instead
of per word, also change kyber, mq-deadline and bfq to follow this,
a new helper __map_depth_with_shallow() is introduced to calculate
available bits in each word.

Signed-off-by: Yu Kuai &lt;yukuai3@huawei.com&gt;
Link: https://lore.kernel.org/r/20250807032413.1469456-2-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 42e6c6ce03fd3e41e39a0f93f9b1a1d9fa664338 ]

Currently elevators will record internal 'async_depth' to throttle
asynchronous requests, and they both calculate shallow_dpeth based on
sb-&gt;shift, with the respect that sb-&gt;shift is the available tags in one
word.

However, sb-&gt;shift is not the availbale tags in the last word, see
__map_depth:

if (index == sb-&gt;map_nr - 1)
  return sb-&gt;depth - (index &lt;&lt; sb-&gt;shift);

For consequence, if the last word is used, more tags can be get than
expected, for example, assume nr_requests=256 and there are four words,
in the worst case if user set nr_requests=32, then the first word is
the last word, and still use bits per word, which is 64, to calculate
async_depth is wrong.

One the ohter hand, due to cgroup qos, bfq can allow only one request
to be allocated, and set shallow_dpeth=1 will still allow the number
of words request to be allocated.

Fix this problems by using shallow_depth to the whole sbitmap instead
of per word, also change kyber, mq-deadline and bfq to follow this,
a new helper __map_depth_with_shallow() is introduced to calculate
available bits in each word.

Signed-off-by: Yu Kuai &lt;yukuai3@huawei.com&gt;
Link: https://lore.kernel.org/r/20250807032413.1469456-2-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>lib/alloc_tag: do not acquire non-existent lock in alloc_tag_top_users()</title>
<updated>2025-07-17T16:37:14+00:00</updated>
<author>
<name>Harry Yoo</name>
<email>harry.yoo@oracle.com</email>
</author>
<published>2025-06-20T19:53:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=febc0b5dbabda414565bdfaaaa59d26f787d5fe7'/>
<id>febc0b5dbabda414565bdfaaaa59d26f787d5fe7</id>
<content type='text'>
commit 99af22cd34688cc0d535a1919e0bea4cbc6c1ea1 upstream.

alloc_tag_top_users() attempts to lock alloc_tag_cttype-&gt;mod_lock even
when the alloc_tag_cttype is not allocated because:

  1) alloc tagging is disabled because mem profiling is disabled
     (!alloc_tag_cttype)
  2) alloc tagging is enabled, but not yet initialized (!alloc_tag_cttype)
  3) alloc tagging is enabled, but failed initialization
     (!alloc_tag_cttype or IS_ERR(alloc_tag_cttype))

In all cases, alloc_tag_cttype is not allocated, and therefore
alloc_tag_top_users() should not attempt to acquire the semaphore.

This leads to a crash on memory allocation failure by attempting to
acquire a non-existent semaphore:

  Oops: general protection fault, probably for non-canonical address 0xdffffc000000001b: 0000 [#3] SMP KASAN NOPTI
  KASAN: null-ptr-deref in range [0x00000000000000d8-0x00000000000000df]
  CPU: 2 UID: 0 PID: 1 Comm: systemd Tainted: G      D             6.16.0-rc2 #1 VOLUNTARY
  Tainted: [D]=DIE
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
  RIP: 0010:down_read_trylock+0xaa/0x3b0
  Code: d0 7c 08 84 d2 0f 85 a0 02 00 00 8b 0d df 31 dd 04 85 c9 75 29 48 b8 00 00 00 00 00 fc ff df 48 8d 6b 68 48 89 ea 48 c1 ea 03 &lt;80&gt; 3c 02 00 0f 85 88 02 00 00 48 3b 5b 68 0f 85 53 01 00 00 65 ff
  RSP: 0000:ffff8881002ce9b8 EFLAGS: 00010016
  RAX: dffffc0000000000 RBX: 0000000000000070 RCX: 0000000000000000
  RDX: 000000000000001b RSI: 000000000000000a RDI: 0000000000000070
  RBP: 00000000000000d8 R08: 0000000000000001 R09: ffffed107dde49d1
  R10: ffff8883eef24e8b R11: ffff8881002cec20 R12: 1ffff11020059d37
  R13: 00000000003fff7b R14: ffff8881002cec20 R15: dffffc0000000000
  FS:  00007f963f21d940(0000) GS:ffff888458ca6000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f963f5edf71 CR3: 000000010672c000 CR4: 0000000000350ef0
  Call Trace:
   &lt;TASK&gt;
   codetag_trylock_module_list+0xd/0x20
   alloc_tag_top_users+0x369/0x4b0
   __show_mem+0x1cd/0x6e0
   warn_alloc+0x2b1/0x390
   __alloc_frozen_pages_noprof+0x12b9/0x21a0
   alloc_pages_mpol+0x135/0x3e0
   alloc_slab_page+0x82/0xe0
   new_slab+0x212/0x240
   ___slab_alloc+0x82a/0xe00
   &lt;/TASK&gt;

As David Wang points out, this issue became easier to trigger after commit
780138b12381 ("alloc_tag: check mem_profiling_support in alloc_tag_init").

Before the commit, the issue occurred only when it failed to allocate and
initialize alloc_tag_cttype or if a memory allocation fails before
alloc_tag_init() is called.  After the commit, it can be easily triggered
when memory profiling is compiled but disabled at boot.

To properly determine whether alloc_tag_init() has been called and its
data structures initialized, verify that alloc_tag_cttype is a valid
pointer before acquiring the semaphore.  If the variable is NULL or an
error value, it has not been properly initialized.  In such a case, just
skip and do not attempt to acquire the semaphore.

[harry.yoo@oracle.com: v3]
  Link: https://lkml.kernel.org/r/20250624072513.84219-1-harry.yoo@oracle.com
Link: https://lkml.kernel.org/r/20250620195305.1115151-1-harry.yoo@oracle.com
Fixes: 780138b12381 ("alloc_tag: check mem_profiling_support in alloc_tag_init")
Fixes: 1438d349d16b ("lib: add memory allocations report in show_mem()")
Signed-off-by: Harry Yoo &lt;harry.yoo@oracle.com&gt;
Reported-by: kernel test robot &lt;oliver.sang@intel.com&gt;
Closes: https://lore.kernel.org/oe-lkp/202506181351.bba867dd-lkp@intel.com
Acked-by: Suren Baghdasaryan &lt;surenb@google.com&gt;
Tested-by: Raghavendra K T &lt;raghavendra.kt@amd.com&gt;
Cc: Casey Chen &lt;cachen@purestorage.com&gt;
Cc: David Wang &lt;00107082@163.com&gt;
Cc: Kent Overstreet &lt;kent.overstreet@linux.dev&gt;
Cc: Yuanyuan Zhong &lt;yzhong@purestorage.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 99af22cd34688cc0d535a1919e0bea4cbc6c1ea1 upstream.

alloc_tag_top_users() attempts to lock alloc_tag_cttype-&gt;mod_lock even
when the alloc_tag_cttype is not allocated because:

  1) alloc tagging is disabled because mem profiling is disabled
     (!alloc_tag_cttype)
  2) alloc tagging is enabled, but not yet initialized (!alloc_tag_cttype)
  3) alloc tagging is enabled, but failed initialization
     (!alloc_tag_cttype or IS_ERR(alloc_tag_cttype))

In all cases, alloc_tag_cttype is not allocated, and therefore
alloc_tag_top_users() should not attempt to acquire the semaphore.

This leads to a crash on memory allocation failure by attempting to
acquire a non-existent semaphore:

  Oops: general protection fault, probably for non-canonical address 0xdffffc000000001b: 0000 [#3] SMP KASAN NOPTI
  KASAN: null-ptr-deref in range [0x00000000000000d8-0x00000000000000df]
  CPU: 2 UID: 0 PID: 1 Comm: systemd Tainted: G      D             6.16.0-rc2 #1 VOLUNTARY
  Tainted: [D]=DIE
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
  RIP: 0010:down_read_trylock+0xaa/0x3b0
  Code: d0 7c 08 84 d2 0f 85 a0 02 00 00 8b 0d df 31 dd 04 85 c9 75 29 48 b8 00 00 00 00 00 fc ff df 48 8d 6b 68 48 89 ea 48 c1 ea 03 &lt;80&gt; 3c 02 00 0f 85 88 02 00 00 48 3b 5b 68 0f 85 53 01 00 00 65 ff
  RSP: 0000:ffff8881002ce9b8 EFLAGS: 00010016
  RAX: dffffc0000000000 RBX: 0000000000000070 RCX: 0000000000000000
  RDX: 000000000000001b RSI: 000000000000000a RDI: 0000000000000070
  RBP: 00000000000000d8 R08: 0000000000000001 R09: ffffed107dde49d1
  R10: ffff8883eef24e8b R11: ffff8881002cec20 R12: 1ffff11020059d37
  R13: 00000000003fff7b R14: ffff8881002cec20 R15: dffffc0000000000
  FS:  00007f963f21d940(0000) GS:ffff888458ca6000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f963f5edf71 CR3: 000000010672c000 CR4: 0000000000350ef0
  Call Trace:
   &lt;TASK&gt;
   codetag_trylock_module_list+0xd/0x20
   alloc_tag_top_users+0x369/0x4b0
   __show_mem+0x1cd/0x6e0
   warn_alloc+0x2b1/0x390
   __alloc_frozen_pages_noprof+0x12b9/0x21a0
   alloc_pages_mpol+0x135/0x3e0
   alloc_slab_page+0x82/0xe0
   new_slab+0x212/0x240
   ___slab_alloc+0x82a/0xe00
   &lt;/TASK&gt;

As David Wang points out, this issue became easier to trigger after commit
780138b12381 ("alloc_tag: check mem_profiling_support in alloc_tag_init").

Before the commit, the issue occurred only when it failed to allocate and
initialize alloc_tag_cttype or if a memory allocation fails before
alloc_tag_init() is called.  After the commit, it can be easily triggered
when memory profiling is compiled but disabled at boot.

To properly determine whether alloc_tag_init() has been called and its
data structures initialized, verify that alloc_tag_cttype is a valid
pointer before acquiring the semaphore.  If the variable is NULL or an
error value, it has not been properly initialized.  In such a case, just
skip and do not attempt to acquire the semaphore.

[harry.yoo@oracle.com: v3]
  Link: https://lkml.kernel.org/r/20250624072513.84219-1-harry.yoo@oracle.com
Link: https://lkml.kernel.org/r/20250620195305.1115151-1-harry.yoo@oracle.com
Fixes: 780138b12381 ("alloc_tag: check mem_profiling_support in alloc_tag_init")
Fixes: 1438d349d16b ("lib: add memory allocations report in show_mem()")
Signed-off-by: Harry Yoo &lt;harry.yoo@oracle.com&gt;
Reported-by: kernel test robot &lt;oliver.sang@intel.com&gt;
Closes: https://lore.kernel.org/oe-lkp/202506181351.bba867dd-lkp@intel.com
Acked-by: Suren Baghdasaryan &lt;surenb@google.com&gt;
Tested-by: Raghavendra K T &lt;raghavendra.kt@amd.com&gt;
Cc: Casey Chen &lt;cachen@purestorage.com&gt;
Cc: David Wang &lt;00107082@163.com&gt;
Cc: Kent Overstreet &lt;kent.overstreet@linux.dev&gt;
Cc: Yuanyuan Zhong &lt;yzhong@purestorage.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>maple_tree: fix mt_destroy_walk() on root leaf node</title>
<updated>2025-07-17T16:37:13+00:00</updated>
<author>
<name>Wei Yang</name>
<email>richard.weiyang@gmail.com</email>
</author>
<published>2025-06-24T19:18:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=839d8682732e40056d9132f3da4e5386948a8776'/>
<id>839d8682732e40056d9132f3da4e5386948a8776</id>
<content type='text'>
commit ea9b77f98d94c4d5c1bd1ac1db078f78b40e8bf5 upstream.

On destroy, we should set each node dead.  But current code miss this when
the maple tree has only the root node.

The reason is mt_destroy_walk() leverage mte_destroy_descend() to set node
dead, but this is skipped since the only root node is a leaf.

Fixes this by setting the node dead if it is a leaf.

Link: https://lore.kernel.org/all/20250407231354.11771-1-richard.weiyang@gmail.com/
Link: https://lkml.kernel.org/r/20250624191841.64682-1-Liam.Howlett@oracle.com
Fixes: 54a611b60590 ("Maple Tree: add new data structure")
Signed-off-by: Wei Yang &lt;richard.weiyang@gmail.com&gt;
Signed-off-by: Liam R. Howlett &lt;Liam.Howlett@oracle.com&gt;
Reviewed-by: Dev Jain &lt;dev.jain@arm.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit ea9b77f98d94c4d5c1bd1ac1db078f78b40e8bf5 upstream.

On destroy, we should set each node dead.  But current code miss this when
the maple tree has only the root node.

The reason is mt_destroy_walk() leverage mte_destroy_descend() to set node
dead, but this is skipped since the only root node is a leaf.

Fixes this by setting the node dead if it is a leaf.

Link: https://lore.kernel.org/all/20250407231354.11771-1-richard.weiyang@gmail.com/
Link: https://lkml.kernel.org/r/20250624191841.64682-1-Liam.Howlett@oracle.com
Fixes: 54a611b60590 ("Maple Tree: add new data structure")
Signed-off-by: Wei Yang &lt;richard.weiyang@gmail.com&gt;
Signed-off-by: Liam R. Howlett &lt;Liam.Howlett@oracle.com&gt;
Reviewed-by: Dev Jain &lt;dev.jain@arm.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
