<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/arch/um, branch v5.4.271</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>um: net: Fix return type of uml_net_start_xmit()</title>
<updated>2024-02-23T07:25:02+00:00</updated>
<author>
<name>Nathan Chancellor</name>
<email>nathan@kernel.org</email>
</author>
<published>2023-12-06T16:49:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a6946682ddcbb27e1019fe24294548e11f72f8c6'/>
<id>a6946682ddcbb27e1019fe24294548e11f72f8c6</id>
<content type='text'>
[ Upstream commit 7d748f60a4b82b50bf25fad1bd42d33f049f76aa ]

With clang's kernel control flow integrity (kCFI, CONFIG_CFI_CLANG),
indirect call targets are validated against the expected function
pointer prototype to make sure the call target is valid to help mitigate
ROP attacks. If they are not identical, there is a failure at run time,
which manifests as either a kernel panic or thread getting killed. A
warning in clang aims to catch these at compile time, which reveals:

  arch/um/drivers/net_kern.c:353:21: warning: incompatible function pointer types initializing 'netdev_tx_t (*)(struct sk_buff *, struct net_device *)' (aka 'enum netdev_tx (*)(struct sk_buff *, struct net_device *)') with an expression of type 'int (struct sk_buff *, struct net_device *)' [-Wincompatible-function-pointer-types-strict]
    353 |         .ndo_start_xmit         = uml_net_start_xmit,
        |                                   ^~~~~~~~~~~~~~~~~~
  1 warning generated.

-&gt;ndo_start_xmit() in 'struct net_device_ops' expects a return type of
'netdev_tx_t', not 'int'. Adjust the return type of uml_net_start_xmit()
to match the prototype's to resolve the warning. While UML does not
currently implement support for kCFI, it could in the future, which
means this warning becomes a fatal CFI failure at run time.

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Closes: https://lore.kernel.org/oe-kbuild-all/202310031340.v1vPh207-lkp@intel.com/
Acked-by: Anton Ivanov &lt;anton.ivanov@cambridgegreys.com&gt;
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&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 7d748f60a4b82b50bf25fad1bd42d33f049f76aa ]

With clang's kernel control flow integrity (kCFI, CONFIG_CFI_CLANG),
indirect call targets are validated against the expected function
pointer prototype to make sure the call target is valid to help mitigate
ROP attacks. If they are not identical, there is a failure at run time,
which manifests as either a kernel panic or thread getting killed. A
warning in clang aims to catch these at compile time, which reveals:

  arch/um/drivers/net_kern.c:353:21: warning: incompatible function pointer types initializing 'netdev_tx_t (*)(struct sk_buff *, struct net_device *)' (aka 'enum netdev_tx (*)(struct sk_buff *, struct net_device *)') with an expression of type 'int (struct sk_buff *, struct net_device *)' [-Wincompatible-function-pointer-types-strict]
    353 |         .ndo_start_xmit         = uml_net_start_xmit,
        |                                   ^~~~~~~~~~~~~~~~~~
  1 warning generated.

-&gt;ndo_start_xmit() in 'struct net_device_ops' expects a return type of
'netdev_tx_t', not 'int'. Adjust the return type of uml_net_start_xmit()
to match the prototype's to resolve the warning. While UML does not
currently implement support for kCFI, it could in the future, which
means this warning becomes a fatal CFI failure at run time.

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Closes: https://lore.kernel.org/oe-kbuild-all/202310031340.v1vPh207-lkp@intel.com/
Acked-by: Anton Ivanov &lt;anton.ivanov@cambridgegreys.com&gt;
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>um: Don't use vfprintf() for os_info()</title>
<updated>2024-02-23T07:25:02+00:00</updated>
<author>
<name>Benjamin Berg</name>
<email>benjamin@sipsolutions.net</email>
</author>
<published>2023-11-10T11:03:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c8115f2bd8ef3c081e382754eb270a1b1fe47b32'/>
<id>c8115f2bd8ef3c081e382754eb270a1b1fe47b32</id>
<content type='text'>
[ Upstream commit 236f9fe39b02c15fa5530b53e9cca48354394389 ]

The threads allocated inside the kernel have only a single page of
stack. Unfortunately, the vfprintf function in standard glibc may use
too much stack-space, overflowing it.

To make os_info safe to be used by helper threads, use the kernel
vscnprintf function into a smallish buffer and write out the information
to stderr.

Signed-off-by: Benjamin Berg &lt;benjamin@sipsolutions.net&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&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 236f9fe39b02c15fa5530b53e9cca48354394389 ]

The threads allocated inside the kernel have only a single page of
stack. Unfortunately, the vfprintf function in standard glibc may use
too much stack-space, overflowing it.

To make os_info safe to be used by helper threads, use the kernel
vscnprintf function into a smallish buffer and write out the information
to stderr.

Signed-off-by: Benjamin Berg &lt;benjamin@sipsolutions.net&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>um: Fix naming clash between UML and scheduler</title>
<updated>2024-02-23T07:25:02+00:00</updated>
<author>
<name>Anton Ivanov</name>
<email>anton.ivanov@cambridgegreys.com</email>
</author>
<published>2023-09-21T14:34:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=735a29ce08ab3eb6e00b2563e259efdc7b792a99'/>
<id>735a29ce08ab3eb6e00b2563e259efdc7b792a99</id>
<content type='text'>
[ Upstream commit 541d4e4d435c8b9bfd29f70a1da4a2db97794e0a ]

__cant_sleep was already used and exported by the scheduler.
The name had to be changed to a UML specific one.

Signed-off-by: Anton Ivanov &lt;anton.ivanov@cambridgegreys.com&gt;
Reviewed-by: Peter Lafreniere &lt;peter@n8pjl.ca&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&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 541d4e4d435c8b9bfd29f70a1da4a2db97794e0a ]

__cant_sleep was already used and exported by the scheduler.
The name had to be changed to a UML specific one.

Signed-off-by: Anton Ivanov &lt;anton.ivanov@cambridgegreys.com&gt;
Reviewed-by: Peter Lafreniere &lt;peter@n8pjl.ca&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>um: Fix hostaudio build errors</title>
<updated>2023-09-23T08:59:53+00:00</updated>
<author>
<name>Randy Dunlap</name>
<email>rdunlap@infradead.org</email>
</author>
<published>2023-08-02T05:15:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e0f2d85ea3d0214a9c2a213ba5ab56183b4ff96e'/>
<id>e0f2d85ea3d0214a9c2a213ba5ab56183b4ff96e</id>
<content type='text'>
[ Upstream commit db4bfcba7bb8d10f00bba2a3da6b9a9c2a1d7b71 ]

Use "select" to ensure that the required kconfig symbols are set
as expected.
Drop HOSTAUDIO since it is now equivalent to UML_SOUND.

Set CONFIG_SOUND=m in ARCH=um defconfig files to maintain the
status quo of the default configs.

Allow SOUND with UML regardless of HAS_IOMEM. Otherwise there is a
kconfig warning for unmet dependencies. (This was not an issue when
SOUND was defined in arch/um/drivers/Kconfig. I have done 50 randconfig
builds and didn't find any issues.)

This fixes build errors when CONFIG_SOUND is not set:

ld: arch/um/drivers/hostaudio_kern.o: in function `hostaudio_cleanup_module':
hostaudio_kern.c:(.exit.text+0xa): undefined reference to `unregister_sound_mixer'
ld: hostaudio_kern.c:(.exit.text+0x15): undefined reference to `unregister_sound_dsp'
ld: arch/um/drivers/hostaudio_kern.o: in function `hostaudio_init_module':
hostaudio_kern.c:(.init.text+0x19): undefined reference to `register_sound_dsp'
ld: hostaudio_kern.c:(.init.text+0x31): undefined reference to `register_sound_mixer'
ld: hostaudio_kern.c:(.init.text+0x49): undefined reference to `unregister_sound_dsp'

and this kconfig warning:
WARNING: unmet direct dependencies detected for SOUND

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Fixes: d886e87cb82b ("sound: make OSS sound core optional")
Signed-off-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Closes: lore.kernel.org/r/202307141416.vxuRVpFv-lkp@intel.com
Cc: Richard Weinberger &lt;richard@nod.at&gt;
Cc: Anton Ivanov &lt;anton.ivanov@cambridgegreys.com&gt;
Cc: Johannes Berg &lt;johannes@sipsolutions.net&gt;
Cc: linux-um@lists.infradead.org
Cc: Tejun Heo &lt;tj@kernel.org&gt;
Cc: Takashi Iwai &lt;tiwai@suse.de&gt;
Cc: Jaroslav Kysela &lt;perex@perex.cz&gt;
Cc: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Nicolas Schier &lt;nicolas@fjasle.eu&gt;
Cc: linux-kbuild@vger.kernel.org
Cc: alsa-devel@alsa-project.org
Reviewed-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&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 db4bfcba7bb8d10f00bba2a3da6b9a9c2a1d7b71 ]

Use "select" to ensure that the required kconfig symbols are set
as expected.
Drop HOSTAUDIO since it is now equivalent to UML_SOUND.

Set CONFIG_SOUND=m in ARCH=um defconfig files to maintain the
status quo of the default configs.

Allow SOUND with UML regardless of HAS_IOMEM. Otherwise there is a
kconfig warning for unmet dependencies. (This was not an issue when
SOUND was defined in arch/um/drivers/Kconfig. I have done 50 randconfig
builds and didn't find any issues.)

This fixes build errors when CONFIG_SOUND is not set:

ld: arch/um/drivers/hostaudio_kern.o: in function `hostaudio_cleanup_module':
hostaudio_kern.c:(.exit.text+0xa): undefined reference to `unregister_sound_mixer'
ld: hostaudio_kern.c:(.exit.text+0x15): undefined reference to `unregister_sound_dsp'
ld: arch/um/drivers/hostaudio_kern.o: in function `hostaudio_init_module':
hostaudio_kern.c:(.init.text+0x19): undefined reference to `register_sound_dsp'
ld: hostaudio_kern.c:(.init.text+0x31): undefined reference to `register_sound_mixer'
ld: hostaudio_kern.c:(.init.text+0x49): undefined reference to `unregister_sound_dsp'

and this kconfig warning:
WARNING: unmet direct dependencies detected for SOUND

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Fixes: d886e87cb82b ("sound: make OSS sound core optional")
Signed-off-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Closes: lore.kernel.org/r/202307141416.vxuRVpFv-lkp@intel.com
Cc: Richard Weinberger &lt;richard@nod.at&gt;
Cc: Anton Ivanov &lt;anton.ivanov@cambridgegreys.com&gt;
Cc: Johannes Berg &lt;johannes@sipsolutions.net&gt;
Cc: linux-um@lists.infradead.org
Cc: Tejun Heo &lt;tj@kernel.org&gt;
Cc: Takashi Iwai &lt;tiwai@suse.de&gt;
Cc: Jaroslav Kysela &lt;perex@perex.cz&gt;
Cc: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Nicolas Schier &lt;nicolas@fjasle.eu&gt;
Cc: linux-kbuild@vger.kernel.org
Cc: alsa-devel@alsa-project.org
Reviewed-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>um/cpu: Switch to arch_cpu_finalize_init()</title>
<updated>2023-08-08T17:56:34+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2023-06-13T23:39:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a03ef708788eba340a68f5991c7f2962a391a8a5'/>
<id>a03ef708788eba340a68f5991c7f2962a391a8a5</id>
<content type='text'>
commit 9349b5cd0908f8afe95529fc7a8cbb1417df9b0c upstream

check_bugs() is about to be phased out. Switch over to the new
arch_cpu_finalize_init() implementation.

No functional change.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: Richard Weinberger &lt;richard@nod.at&gt;
Link: https://lore.kernel.org/r/20230613224545.493148694@linutronix.de
Signed-off-by: Daniel Sneddon &lt;daniel.sneddon@linux.intel.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 9349b5cd0908f8afe95529fc7a8cbb1417df9b0c upstream

check_bugs() is about to be phased out. Switch over to the new
arch_cpu_finalize_init() implementation.

No functional change.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: Richard Weinberger &lt;richard@nod.at&gt;
Link: https://lore.kernel.org/r/20230613224545.493148694@linutronix.de
Signed-off-by: Daniel Sneddon &lt;daniel.sneddon@linux.intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>UML: define RUNTIME_DISCARD_EXIT</title>
<updated>2023-03-17T07:32:54+00:00</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2023-02-07T16:41:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7a934a77f11a68b3f3a73f64ee10880bfeacaf79'/>
<id>7a934a77f11a68b3f3a73f64ee10880bfeacaf79</id>
<content type='text'>
commit b99ddbe8336ee680257c8ab479f75051eaa49dcf upstream.

With CONFIG_VIRTIO_UML=y, GNU ld &lt; 2.36 fails to link UML vmlinux
(w/wo CONFIG_LD_SCRIPT_STATIC).

  `.exit.text' referenced in section `.uml.exitcall.exit' of arch/um/drivers/virtio_uml.o: defined in discarded section `.exit.text' of arch/um/drivers/virtio_uml.o
  collect2: error: ld returned 1 exit status

This fix is similar to the following commits:

- 4b9880dbf3bd ("powerpc/vmlinux.lds: Define RUNTIME_DISCARD_EXIT")
- a494398bde27 ("s390: define RUNTIME_DISCARD_EXIT to fix link error
  with GNU ld &lt; 2.36")
- c1c551bebf92 ("sh: define RUNTIME_DISCARD_EXIT")

Fixes: 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv")
Reported-by: SeongJae Park &lt;sj@kernel.org&gt;
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Tested-by: SeongJae Park &lt;sj@kernel.org&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&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 b99ddbe8336ee680257c8ab479f75051eaa49dcf upstream.

With CONFIG_VIRTIO_UML=y, GNU ld &lt; 2.36 fails to link UML vmlinux
(w/wo CONFIG_LD_SCRIPT_STATIC).

  `.exit.text' referenced in section `.uml.exitcall.exit' of arch/um/drivers/virtio_uml.o: defined in discarded section `.exit.text' of arch/um/drivers/virtio_uml.o
  collect2: error: ld returned 1 exit status

This fix is similar to the following commits:

- 4b9880dbf3bd ("powerpc/vmlinux.lds: Define RUNTIME_DISCARD_EXIT")
- a494398bde27 ("s390: define RUNTIME_DISCARD_EXIT to fix link error
  with GNU ld &lt; 2.36")
- c1c551bebf92 ("sh: define RUNTIME_DISCARD_EXIT")

Fixes: 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv")
Reported-by: SeongJae Park &lt;sj@kernel.org&gt;
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Tested-by: SeongJae Park &lt;sj@kernel.org&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>um: vector: Fix memory leak in vector_config</title>
<updated>2023-03-11T15:44:08+00:00</updated>
<author>
<name>Xiang Yang</name>
<email>xiangyang3@huawei.com</email>
</author>
<published>2022-11-15T07:32:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6480c3a12755bf85d6738ab60967e89b809c701a'/>
<id>6480c3a12755bf85d6738ab60967e89b809c701a</id>
<content type='text'>
[ Upstream commit 8f88c73afe481f93d40801596927e8c0047b6d96 ]

If the return value of the uml_parse_vector_ifspec function is NULL,
we should call kfree(params) to prevent memory leak.

Fixes: 49da7e64f33e ("High Performance UML Vector Network Driver")
Signed-off-by: Xiang Yang &lt;xiangyang3@huawei.com&gt;
Acked-By: Anton Ivanov &lt;anton.ivanov@kot-begemot.co.uk&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&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 8f88c73afe481f93d40801596927e8c0047b6d96 ]

If the return value of the uml_parse_vector_ifspec function is NULL,
we should call kfree(params) to prevent memory leak.

Fixes: 49da7e64f33e ("High Performance UML Vector Network Driver")
Signed-off-by: Xiang Yang &lt;xiangyang3@huawei.com&gt;
Acked-By: Anton Ivanov &lt;anton.ivanov@kot-begemot.co.uk&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>UM: cpuinfo: Fix a warning for CONFIG_CPUMASK_OFFSTACK</title>
<updated>2022-10-26T11:22:16+00:00</updated>
<author>
<name>Huacai Chen</name>
<email>chenhuacai@loongson.cn</email>
</author>
<published>2022-07-12T07:52:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=cd251d39b13485eb94ee65bb000d024e02c00e45'/>
<id>cd251d39b13485eb94ee65bb000d024e02c00e45</id>
<content type='text'>
commit 16c546e148fa6d14a019431436a6f7b4087dbccd upstream.

When CONFIG_CPUMASK_OFFSTACK and CONFIG_DEBUG_PER_CPU_MAPS is selected,
cpu_max_bits_warn() generates a runtime warning similar as below while
we show /proc/cpuinfo. Fix this by using nr_cpu_ids (the runtime limit)
instead of NR_CPUS to iterate CPUs.

[    3.052463] ------------[ cut here ]------------
[    3.059679] WARNING: CPU: 3 PID: 1 at include/linux/cpumask.h:108 show_cpuinfo+0x5e8/0x5f0
[    3.070072] Modules linked in: efivarfs autofs4
[    3.076257] CPU: 0 PID: 1 Comm: systemd Not tainted 5.19-rc5+ #1052
[    3.099465] Stack : 9000000100157b08 9000000000f18530 9000000000cf846c 9000000100154000
[    3.109127]         9000000100157a50 0000000000000000 9000000100157a58 9000000000ef7430
[    3.118774]         90000001001578e8 0000000000000040 0000000000000020 ffffffffffffffff
[    3.128412]         0000000000aaaaaa 1ab25f00eec96a37 900000010021de80 900000000101c890
[    3.138056]         0000000000000000 0000000000000000 0000000000000000 0000000000aaaaaa
[    3.147711]         ffff8000339dc220 0000000000000001 0000000006ab4000 0000000000000000
[    3.157364]         900000000101c998 0000000000000004 9000000000ef7430 0000000000000000
[    3.167012]         0000000000000009 000000000000006c 0000000000000000 0000000000000000
[    3.176641]         9000000000d3de08 9000000001639390 90000000002086d8 00007ffff0080286
[    3.186260]         00000000000000b0 0000000000000004 0000000000000000 0000000000071c1c
[    3.195868]         ...
[    3.199917] Call Trace:
[    3.203941] [&lt;90000000002086d8&gt;] show_stack+0x38/0x14c
[    3.210666] [&lt;9000000000cf846c&gt;] dump_stack_lvl+0x60/0x88
[    3.217625] [&lt;900000000023d268&gt;] __warn+0xd0/0x100
[    3.223958] [&lt;9000000000cf3c90&gt;] warn_slowpath_fmt+0x7c/0xcc
[    3.231150] [&lt;9000000000210220&gt;] show_cpuinfo+0x5e8/0x5f0
[    3.238080] [&lt;90000000004f578c&gt;] seq_read_iter+0x354/0x4b4
[    3.245098] [&lt;90000000004c2e90&gt;] new_sync_read+0x17c/0x1c4
[    3.252114] [&lt;90000000004c5174&gt;] vfs_read+0x138/0x1d0
[    3.258694] [&lt;90000000004c55f8&gt;] ksys_read+0x70/0x100
[    3.265265] [&lt;9000000000cfde9c&gt;] do_syscall+0x7c/0x94
[    3.271820] [&lt;9000000000202fe4&gt;] handle_syscall+0xc4/0x160
[    3.281824] ---[ end trace 8b484262b4b8c24c ]---

Cc: stable@vger.kernel.org
Signed-off-by: Huacai Chen &lt;chenhuacai@loongson.cn&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&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 16c546e148fa6d14a019431436a6f7b4087dbccd upstream.

When CONFIG_CPUMASK_OFFSTACK and CONFIG_DEBUG_PER_CPU_MAPS is selected,
cpu_max_bits_warn() generates a runtime warning similar as below while
we show /proc/cpuinfo. Fix this by using nr_cpu_ids (the runtime limit)
instead of NR_CPUS to iterate CPUs.

[    3.052463] ------------[ cut here ]------------
[    3.059679] WARNING: CPU: 3 PID: 1 at include/linux/cpumask.h:108 show_cpuinfo+0x5e8/0x5f0
[    3.070072] Modules linked in: efivarfs autofs4
[    3.076257] CPU: 0 PID: 1 Comm: systemd Not tainted 5.19-rc5+ #1052
[    3.099465] Stack : 9000000100157b08 9000000000f18530 9000000000cf846c 9000000100154000
[    3.109127]         9000000100157a50 0000000000000000 9000000100157a58 9000000000ef7430
[    3.118774]         90000001001578e8 0000000000000040 0000000000000020 ffffffffffffffff
[    3.128412]         0000000000aaaaaa 1ab25f00eec96a37 900000010021de80 900000000101c890
[    3.138056]         0000000000000000 0000000000000000 0000000000000000 0000000000aaaaaa
[    3.147711]         ffff8000339dc220 0000000000000001 0000000006ab4000 0000000000000000
[    3.157364]         900000000101c998 0000000000000004 9000000000ef7430 0000000000000000
[    3.167012]         0000000000000009 000000000000006c 0000000000000000 0000000000000000
[    3.176641]         9000000000d3de08 9000000001639390 90000000002086d8 00007ffff0080286
[    3.186260]         00000000000000b0 0000000000000004 0000000000000000 0000000000071c1c
[    3.195868]         ...
[    3.199917] Call Trace:
[    3.203941] [&lt;90000000002086d8&gt;] show_stack+0x38/0x14c
[    3.210666] [&lt;9000000000cf846c&gt;] dump_stack_lvl+0x60/0x88
[    3.217625] [&lt;900000000023d268&gt;] __warn+0xd0/0x100
[    3.223958] [&lt;9000000000cf3c90&gt;] warn_slowpath_fmt+0x7c/0xcc
[    3.231150] [&lt;9000000000210220&gt;] show_cpuinfo+0x5e8/0x5f0
[    3.238080] [&lt;90000000004f578c&gt;] seq_read_iter+0x354/0x4b4
[    3.245098] [&lt;90000000004c2e90&gt;] new_sync_read+0x17c/0x1c4
[    3.252114] [&lt;90000000004c5174&gt;] vfs_read+0x138/0x1d0
[    3.258694] [&lt;90000000004c55f8&gt;] ksys_read+0x70/0x100
[    3.265265] [&lt;9000000000cfde9c&gt;] do_syscall+0x7c/0x94
[    3.271820] [&lt;9000000000202fe4&gt;] handle_syscall+0xc4/0x160
[    3.281824] ---[ end trace 8b484262b4b8c24c ]---

Cc: stable@vger.kernel.org
Signed-off-by: Huacai Chen &lt;chenhuacai@loongson.cn&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arch: um: Mark the stack non-executable to fix a binutils warning</title>
<updated>2022-10-15T05:54:38+00:00</updated>
<author>
<name>David Gow</name>
<email>davidgow@google.com</email>
</author>
<published>2022-09-21T06:48:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d2f3a51ca27ef6b980d456c9aadfe9b1bc0184f7'/>
<id>d2f3a51ca27ef6b980d456c9aadfe9b1bc0184f7</id>
<content type='text'>
[ Upstream commit bd71558d585ac61cfd799db7f25e78dca404dd7a ]

Since binutils 2.39, ld will print a warning if any stack section is
executable, which is the default for stack sections on files without a
.note.GNU-stack section.

This was fixed for x86 in commit ffcf9c5700e4 ("x86: link vdso and boot with -z noexecstack --no-warn-rwx-segments"),
but remained broken for UML, resulting in several warnings:

/usr/bin/ld: warning: arch/x86/um/vdso/vdso.o: missing .note.GNU-stack section implies executable stack
/usr/bin/ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker
/usr/bin/ld: warning: .tmp_vmlinux.kallsyms1 has a LOAD segment with RWX permissions
/usr/bin/ld: warning: .tmp_vmlinux.kallsyms1.o: missing .note.GNU-stack section implies executable stack
/usr/bin/ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker
/usr/bin/ld: warning: .tmp_vmlinux.kallsyms2 has a LOAD segment with RWX permissions
/usr/bin/ld: warning: .tmp_vmlinux.kallsyms2.o: missing .note.GNU-stack section implies executable stack
/usr/bin/ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker
/usr/bin/ld: warning: vmlinux has a LOAD segment with RWX permissions

Link both the VDSO and vmlinux with -z noexecstack, fixing the warnings
about .note.GNU-stack sections. In addition, pass --no-warn-rwx-segments
to dodge the remaining warnings about LOAD segments with RWX permissions
in the kallsyms objects. (Note that this flag is apparently not
available on lld, so hide it behind a test for BFD, which is what the
x86 patch does.)

Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ffcf9c5700e49c0aee42dcba9a12ba21338e8136
Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=ba951afb99912da01a6e8434126b8fac7aa75107
Signed-off-by: David Gow &lt;davidgow@google.com&gt;
Reviewed-by: Lukas Straub &lt;lukasstraub2@web.de&gt;
Tested-by: Lukas Straub &lt;lukasstraub2@web.de&gt;
Acked-by: Randy Dunlap &lt;rdunlap@infradead.org&gt; # build-tested
Signed-off-by: Richard Weinberger &lt;richard@nod.at&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 bd71558d585ac61cfd799db7f25e78dca404dd7a ]

Since binutils 2.39, ld will print a warning if any stack section is
executable, which is the default for stack sections on files without a
.note.GNU-stack section.

This was fixed for x86 in commit ffcf9c5700e4 ("x86: link vdso and boot with -z noexecstack --no-warn-rwx-segments"),
but remained broken for UML, resulting in several warnings:

/usr/bin/ld: warning: arch/x86/um/vdso/vdso.o: missing .note.GNU-stack section implies executable stack
/usr/bin/ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker
/usr/bin/ld: warning: .tmp_vmlinux.kallsyms1 has a LOAD segment with RWX permissions
/usr/bin/ld: warning: .tmp_vmlinux.kallsyms1.o: missing .note.GNU-stack section implies executable stack
/usr/bin/ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker
/usr/bin/ld: warning: .tmp_vmlinux.kallsyms2 has a LOAD segment with RWX permissions
/usr/bin/ld: warning: .tmp_vmlinux.kallsyms2.o: missing .note.GNU-stack section implies executable stack
/usr/bin/ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker
/usr/bin/ld: warning: vmlinux has a LOAD segment with RWX permissions

Link both the VDSO and vmlinux with -z noexecstack, fixing the warnings
about .note.GNU-stack sections. In addition, pass --no-warn-rwx-segments
to dodge the remaining warnings about LOAD segments with RWX permissions
in the kallsyms objects. (Note that this flag is apparently not
available on lld, so hide it behind a test for BFD, which is what the
x86 patch does.)

Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ffcf9c5700e49c0aee42dcba9a12ba21338e8136
Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=ba951afb99912da01a6e8434126b8fac7aa75107
Signed-off-by: David Gow &lt;davidgow@google.com&gt;
Reviewed-by: Lukas Straub &lt;lukasstraub2@web.de&gt;
Tested-by: Lukas Straub &lt;lukasstraub2@web.de&gt;
Acked-by: Randy Dunlap &lt;rdunlap@infradead.org&gt; # build-tested
Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>um: add "noreboot" command line option for PANIC_TIMEOUT=-1 setups</title>
<updated>2022-08-25T09:18:34+00:00</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2022-07-13T11:56:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=082da6a9c30fe0a00458ed36c28b603c86d516cb'/>
<id>082da6a9c30fe0a00458ed36c28b603c86d516cb</id>
<content type='text'>
[ Upstream commit dda520d07b95072a0b63f6c52a8eb566d08ea897 ]

QEMU has a -no-reboot option, which halts instead of reboots when the
guest asks to reboot. This is invaluable when used with
CONFIG_PANIC_TIMEOUT=-1 (and panic_on_warn), because it allows panics
and warnings to be caught immediately in CI. Implement this in UML too,
by way of a basic setup param.

Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&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 dda520d07b95072a0b63f6c52a8eb566d08ea897 ]

QEMU has a -no-reboot option, which halts instead of reboots when the
guest asks to reboot. This is invaluable when used with
CONFIG_PANIC_TIMEOUT=-1 (and panic_on_warn), because it allows panics
and warnings to be caught immediately in CI. Implement this in UML too,
by way of a basic setup param.

Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
