<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/arch/s390/kernel/vdso.c, branch linux-rolling-stable</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>Convert 'alloc_obj' family to use the new default GFP_KERNEL argument</title>
<updated>2026-02-22T01:09:51+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-02-22T00:37:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=bf4afc53b77aeaa48b5409da5c8da6bb4eff7f43'/>
<id>bf4afc53b77aeaa48b5409da5c8da6bb4eff7f43</id>
<content type='text'>
This was done entirely with mindless brute force, using

    git grep -l '\&lt;k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This was done entirely with mindless brute force, using

    git grep -l '\&lt;k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>treewide: Replace kmalloc with kmalloc_obj for non-scalar types</title>
<updated>2026-02-21T09:02:28+00:00</updated>
<author>
<name>Kees Cook</name>
<email>kees@kernel.org</email>
</author>
<published>2026-02-21T07:49:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=69050f8d6d075dc01af7a5f2f550a8067510366f'/>
<id>69050f8d6d075dc01af7a5f2f550a8067510366f</id>
<content type='text'>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook &lt;kees@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook &lt;kees@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/vdso: Rename vdso64 to vdso</title>
<updated>2025-11-25T14:28:07+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>hca@linux.ibm.com</email>
</author>
<published>2025-11-24T15:04:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c0087d807ae86cc82cc356e366d2dccf0e3bb225'/>
<id>c0087d807ae86cc82cc356e366d2dccf0e3bb225</id>
<content type='text'>
Since compat is gone there is only a 64 bit vdso left.
Remove the superfluous "64" suffix everywhere.

Reviewed-by: Jens Remus &lt;jremus@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Since compat is gone there is only a 64 bit vdso left.
Remove the superfluous "64" suffix everywhere.

Reviewed-by: Jens Remus &lt;jremus@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390: Remove compat support</title>
<updated>2025-11-17T10:10:38+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>hca@linux.ibm.com</email>
</author>
<published>2025-11-10T18:54:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8e0b986c59c67e08ada646249f834655a9e6da16'/>
<id>8e0b986c59c67e08ada646249f834655a9e6da16</id>
<content type='text'>
There shouldn't be any 31 bit code around anymore that matters.
Remove the compat layer support required to run 31 bit code.

Reason for removal is code simplification and reduced test effort.

Note that this comes without any deprecation warnings added to config
options, or kernel messages, since most likely those would be ignored
anyway.

If it turns out there is still a reason to keep the compat layer this
can be reverted at any time in the future.

Reviewed-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There shouldn't be any 31 bit code around anymore that matters.
Remove the compat layer support required to run 31 bit code.

Reason for removal is code simplification and reduced test effort.

Note that this comes without any deprecation warnings added to config
options, or kernel messages, since most likely those would be ignored
anyway.

If it turns out there is still a reason to keep the compat layer this
can be reverted at any time in the future.

Reviewed-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mseal sysmap: enable s390</title>
<updated>2025-04-01T22:17:16+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>hca@linux.ibm.com</email>
</author>
<published>2025-03-11T12:33:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=24e3f9fbbd5d93afb41af495c008e76a9005dd06'/>
<id>24e3f9fbbd5d93afb41af495c008e76a9005dd06</id>
<content type='text'>
Provide support for CONFIG_MSEAL_SYSTEM_MAPPINGS on s390, covering the
vdso.

[hca@linux.ibm.com: update supported architectures]
  Link: https://lkml.kernel.org/r/20250317131917.1332402-1-hca@linux.ibm.com
Link: https://lkml.kernel.org/r/20250311123326.2686682-3-hca@linux.ibm.com
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Reviewed-by: Lorenzo Stoakes &lt;lorenzo.stoakes@oracle.com&gt;
Cc: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Cc: Christian Borntraeger &lt;borntraeger@linux.ibm.com&gt;
Cc: Jeff Xu &lt;jeffxu@chromium.org&gt;
Cc: Liam Howlett &lt;liam.howlett@oracle.com&gt;
Cc: Sven Schnelle &lt;svens@linux.ibm.com&gt;
Cc: Thomas Weißschuh &lt;thomas.weissschuh@linutronix.de&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Provide support for CONFIG_MSEAL_SYSTEM_MAPPINGS on s390, covering the
vdso.

[hca@linux.ibm.com: update supported architectures]
  Link: https://lkml.kernel.org/r/20250317131917.1332402-1-hca@linux.ibm.com
Link: https://lkml.kernel.org/r/20250311123326.2686682-3-hca@linux.ibm.com
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Reviewed-by: Lorenzo Stoakes &lt;lorenzo.stoakes@oracle.com&gt;
Cc: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Cc: Christian Borntraeger &lt;borntraeger@linux.ibm.com&gt;
Cc: Jeff Xu &lt;jeffxu@chromium.org&gt;
Cc: Liam Howlett &lt;liam.howlett@oracle.com&gt;
Cc: Sven Schnelle &lt;svens@linux.ibm.com&gt;
Cc: Thomas Weißschuh &lt;thomas.weissschuh@linutronix.de&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/vdso: Switch to generic storage implementation</title>
<updated>2025-02-21T08:54:02+00:00</updated>
<author>
<name>Thomas Weißschuh</name>
<email>thomas.weissschuh@linutronix.de</email>
</author>
<published>2025-02-04T12:05:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9bf39a65b20cd03b10c618b1b1c4703538a5b564'/>
<id>9bf39a65b20cd03b10c618b1b1c4703538a5b564</id>
<content type='text'>
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.

Co-developed-by: Nam Cao &lt;namcao@linutronix.de&gt;
Signed-off-by: Nam Cao &lt;namcao@linutronix.de&gt;
Signed-off-by: Thomas Weißschuh &lt;thomas.weissschuh@linutronix.de&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-12-13a4669dfc8c@linutronix.de

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.

Co-developed-by: Nam Cao &lt;namcao@linutronix.de&gt;
Signed-off-by: Nam Cao &lt;namcao@linutronix.de&gt;
Signed-off-by: Thomas Weißschuh &lt;thomas.weissschuh@linutronix.de&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-12-13a4669dfc8c@linutronix.de

</pre>
</div>
</content>
</entry>
<entry>
<title>s390/vdso: Wire up getrandom() vdso implementation</title>
<updated>2024-09-13T18:57:31+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>hca@linux.ibm.com</email>
</author>
<published>2024-09-13T13:05:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b920aa77be6d57d407b6b6be5d8b4ccc17749cce'/>
<id>b920aa77be6d57d407b6b6be5d8b4ccc17749cce</id>
<content type='text'>
Provide the s390 specific vdso getrandom() architecture backend.

_vdso_rng_data required data is placed within the _vdso_data vvar page,
by using a hardcoded offset larger than vdso_data.

As required the chacha20 implementation does not write to the stack.

The implementation follows more or less the arm64 implementations and
makes use of vector instructions. It has a fallback to the getrandom()
system call for machines where the vector facility is not installed.

The check if the vector facility is installed, as well as an
optimization for machines with the vector-enhancements facility 2, is
implemented with alternatives, avoiding runtime checks.

Note that __kernel_getrandom() is implemented without the vdso user
wrapper which would setup a stack frame for odd cases (aka very old
glibc variants) where the caller has not done that. All callers of
__kernel_getrandom() are required to setup a stack frame, like the C ABI
requires it.

The vdso testcases vdso_test_getrandom and vdso_test_chacha pass.

Benchmark on a z16:

    $ ./vdso_test_getrandom bench-single
       vdso: 25000000 times in 0.493703559 seconds
    syscall: 25000000 times in 6.584025337 seconds

Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Reviewed-by: Harald Freudenberger &lt;freude@linux.ibm.com&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Provide the s390 specific vdso getrandom() architecture backend.

_vdso_rng_data required data is placed within the _vdso_data vvar page,
by using a hardcoded offset larger than vdso_data.

As required the chacha20 implementation does not write to the stack.

The implementation follows more or less the arm64 implementations and
makes use of vector instructions. It has a fallback to the getrandom()
system call for machines where the vector facility is not installed.

The check if the vector facility is installed, as well as an
optimization for machines with the vector-enhancements facility 2, is
implemented with alternatives, avoiding runtime checks.

Note that __kernel_getrandom() is implemented without the vdso user
wrapper which would setup a stack frame for odd cases (aka very old
glibc variants) where the caller has not done that. All callers of
__kernel_getrandom() are required to setup a stack frame, like the C ABI
requires it.

The vdso testcases vdso_test_getrandom and vdso_test_chacha pass.

Benchmark on a z16:

    $ ./vdso_test_getrandom bench-single
       vdso: 25000000 times in 0.493703559 seconds
    syscall: 25000000 times in 6.584025337 seconds

Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Reviewed-by: Harald Freudenberger &lt;freude@linux.ibm.com&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/vdso: Allow alternatives in vdso code</title>
<updated>2024-09-13T15:28:36+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>hca@linux.ibm.com</email>
</author>
<published>2024-09-13T13:05:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e10863fffe3a377a828f876a39cc1c47567b556f'/>
<id>e10863fffe3a377a828f876a39cc1c47567b556f</id>
<content type='text'>
Implement the infrastructure required to allow alternatives in vdso code.

Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Implement the infrastructure required to allow alternatives in vdso code.

Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/stackstrace: Detect vdso stack frames</title>
<updated>2024-05-14T11:37:07+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>hca@linux.ibm.com</email>
</author>
<published>2024-04-29T12:28:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=62b672c4ba90e726cc39b5c3d6dffd1ca817e143'/>
<id>62b672c4ba90e726cc39b5c3d6dffd1ca817e143</id>
<content type='text'>
Clear the backchain of the extra stack frame added by the vdso user wrapper
code. This allows the user stack walker to detect and skip the non-standard
stack frame. Without this an incorrect instruction pointer would be added
to stack traces, and stack frame walking would be continued with a more or
less random back chain.

Fixes: aa44433ac4ee ("s390: add USER_STACKTRACE support")
Reviewed-by: Jens Remus &lt;jremus@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Clear the backchain of the extra stack frame added by the vdso user wrapper
code. This allows the user stack walker to detect and skip the non-standard
stack frame. Without this an incorrect instruction pointer would be added
to stack traces, and stack frame walking would be continued with a more or
less random back chain.

Fixes: aa44433ac4ee ("s390: add USER_STACKTRACE support")
Reviewed-by: Jens Remus &lt;jremus@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/vdso: Use generic union vdso_data_store</title>
<updated>2024-02-20T19:56:00+00:00</updated>
<author>
<name>Anna-Maria Behnsen</name>
<email>anna-maria@linutronix.de</email>
</author>
<published>2024-02-19T15:39:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=cb3444cfdb48b7ee7d208d19c97a29dd8252d884'/>
<id>cb3444cfdb48b7ee7d208d19c97a29dd8252d884</id>
<content type='text'>
There is already a generic union definition for vdso_data_store in the vdso
datapage header.

Use this definition to prevent code duplication.

Signed-off-by: Anna-Maria Behnsen &lt;anna-maria@linutronix.de&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Vincenzo Frascino &lt;vincenzo.frascino@arm.com&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Link: https://lore.kernel.org/r/20240219153939.75719-8-anna-maria@linutronix.de

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There is already a generic union definition for vdso_data_store in the vdso
datapage header.

Use this definition to prevent code duplication.

Signed-off-by: Anna-Maria Behnsen &lt;anna-maria@linutronix.de&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Vincenzo Frascino &lt;vincenzo.frascino@arm.com&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Link: https://lore.kernel.org/r/20240219153939.75719-8-anna-maria@linutronix.de

</pre>
</div>
</content>
</entry>
</feed>
