<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/firmware, branch v5.4.232</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>efi: Accept version 2 of memory attributes table</title>
<updated>2023-02-22T11:50:27+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ardb@kernel.org</email>
</author>
<published>2023-02-02T17:30:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2035cfb9586fa569b2f090131c576ee9184a906d'/>
<id>2035cfb9586fa569b2f090131c576ee9184a906d</id>
<content type='text'>
commit 636ab417a7aec4ee993916e688eb5c5977570836 upstream.

UEFI v2.10 introduces version 2 of the memory attributes table, which
turns the reserved field into a flags field, but is compatible with
version 1 in all other respects. So let's not complain about version 2
if we encounter it.

Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Ard Biesheuvel &lt;ardb@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 636ab417a7aec4ee993916e688eb5c5977570836 upstream.

UEFI v2.10 introduces version 2 of the memory attributes table, which
turns the reserved field into a flags field, but is compatible with
version 1 in all other respects. So let's not complain about version 2
if we encounter it.

Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efi: fix potential NULL deref in efi_mem_reserve_persistent</title>
<updated>2023-02-22T11:50:25+00:00</updated>
<author>
<name>Anton Gusev</name>
<email>aagusev@ispras.ru</email>
</author>
<published>2023-02-03T13:22:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d92a25627bcdf264183670da73c9a60c0bac327e'/>
<id>d92a25627bcdf264183670da73c9a60c0bac327e</id>
<content type='text'>
[ Upstream commit 966d47e1f27c45507c5df82b2a2157e5a4fd3909 ]

When iterating on a linked list, a result of memremap is dereferenced
without checking it for NULL.

This patch adds a check that falls back on allocating a new page in
case memremap doesn't succeed.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 18df7577adae ("efi/memreserve: deal with memreserve entries in unmapped memory")
Signed-off-by: Anton Gusev &lt;aagusev@ispras.ru&gt;
[ardb: return -ENOMEM instead of breaking out of the loop]
Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.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 966d47e1f27c45507c5df82b2a2157e5a4fd3909 ]

When iterating on a linked list, a result of memremap is dereferenced
without checking it for NULL.

This patch adds a check that falls back on allocating a new page in
case memremap doesn't succeed.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 18df7577adae ("efi/memreserve: deal with memreserve entries in unmapped memory")
Signed-off-by: Anton Gusev &lt;aagusev@ispras.ru&gt;
[ardb: return -ENOMEM instead of breaking out of the loop]
Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>gsmi: fix null-deref in gsmi_get_variable</title>
<updated>2023-01-24T06:18:01+00:00</updated>
<author>
<name>Khazhismel Kumykov</name>
<email>khazhy@chromium.org</email>
</author>
<published>2023-01-18T01:02:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ffef77794fb5f1245c3249b86342bad2299accb5'/>
<id>ffef77794fb5f1245c3249b86342bad2299accb5</id>
<content type='text'>
commit a769b05eeed7accc4019a1ed9799dd72067f1ce8 upstream.

We can get EFI variables without fetching the attribute, so we must
allow for that in gsmi.

commit 859748255b43 ("efi: pstore: Omit efivars caching EFI varstore
access layer") added a new get_variable call with attr=NULL, which
triggers panic in gsmi.

Fixes: 74c5b31c6618 ("driver: Google EFI SMI")
Cc: stable &lt;stable@kernel.org&gt;
Signed-off-by: Khazhismel Kumykov &lt;khazhy@google.com&gt;
Link: https://lore.kernel.org/r/20230118010212.1268474-1-khazhy@google.com
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 a769b05eeed7accc4019a1ed9799dd72067f1ce8 upstream.

We can get EFI variables without fetching the attribute, so we must
allow for that in gsmi.

commit 859748255b43 ("efi: pstore: Omit efivars caching EFI varstore
access layer") added a new get_variable call with attr=NULL, which
triggers panic in gsmi.

Fixes: 74c5b31c6618 ("driver: Google EFI SMI")
Cc: stable &lt;stable@kernel.org&gt;
Signed-off-by: Khazhismel Kumykov &lt;khazhy@google.com&gt;
Link: https://lore.kernel.org/r/20230118010212.1268474-1-khazhy@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efi: fix userspace infinite retry read efivars after EFI runtime services page fault</title>
<updated>2023-01-24T06:17:59+00:00</updated>
<author>
<name>Ding Hui</name>
<email>dinghui@sangfor.com.cn</email>
</author>
<published>2022-12-27T15:09:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2e3e2649ea38224a47eaab15fbaa011d19094909'/>
<id>2e3e2649ea38224a47eaab15fbaa011d19094909</id>
<content type='text'>
[ Upstream commit e006ac3003080177cf0b673441a4241f77aaecce ]

After [1][2], if we catch exceptions due to EFI runtime service, we will
clear EFI_RUNTIME_SERVICES bit to disable EFI runtime service, then the
subsequent routine which invoke the EFI runtime service should fail.

But the userspace cat efivars through /sys/firmware/efi/efivars/ will stuck
and infinite loop calling read() due to efivarfs_file_read() return -EINTR.

The -EINTR is converted from EFI_ABORTED by efi_status_to_err(), and is
an improper return value in this situation, so let virt_efi_xxx() return
EFI_DEVICE_ERROR and converted to -EIO to invoker.

Cc: &lt;stable@vger.kernel.org&gt;
Fixes: 3425d934fc03 ("efi/x86: Handle page faults occurring while running EFI runtime services")
Fixes: 23715a26c8d8 ("arm64: efi: Recover from synchronous exceptions occurring in firmware")
Signed-off-by: Ding Hui &lt;dinghui@sangfor.com.cn&gt;
Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.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 e006ac3003080177cf0b673441a4241f77aaecce ]

After [1][2], if we catch exceptions due to EFI runtime service, we will
clear EFI_RUNTIME_SERVICES bit to disable EFI runtime service, then the
subsequent routine which invoke the EFI runtime service should fail.

But the userspace cat efivars through /sys/firmware/efi/efivars/ will stuck
and infinite loop calling read() due to efivarfs_file_read() return -EINTR.

The -EINTR is converted from EFI_ABORTED by efi_status_to_err(), and is
an improper return value in this situation, so let virt_efi_xxx() return
EFI_DEVICE_ERROR and converted to -EIO to invoker.

Cc: &lt;stable@vger.kernel.org&gt;
Fixes: 3425d934fc03 ("efi/x86: Handle page faults occurring while running EFI runtime services")
Fixes: 23715a26c8d8 ("arm64: efi: Recover from synchronous exceptions occurring in firmware")
Signed-off-by: Ding Hui &lt;dinghui@sangfor.com.cn&gt;
Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efi: fix NULL-deref in init error path</title>
<updated>2023-01-18T10:42:06+00:00</updated>
<author>
<name>Johan Hovold</name>
<email>johan+linaro@kernel.org</email>
</author>
<published>2022-12-19T09:10:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5fcf75a8a4c3e7ee9122d143684083c9faf20452'/>
<id>5fcf75a8a4c3e7ee9122d143684083c9faf20452</id>
<content type='text'>
[ Upstream commit 703c13fe3c9af557d312f5895ed6a5fda2711104 ]

In cases where runtime services are not supported or have been disabled,
the runtime services workqueue will never have been allocated.

Do not try to destroy the workqueue unconditionally in the unlikely
event that EFI initialisation fails to avoid dereferencing a NULL
pointer.

Fixes: 98086df8b70c ("efi: add missed destroy_workqueue when efisubsys_init fails")
Cc: stable@vger.kernel.org
Cc: Li Heng &lt;liheng40@huawei.com&gt;
Signed-off-by: Johan Hovold &lt;johan+linaro@kernel.org&gt;
Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.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 703c13fe3c9af557d312f5895ed6a5fda2711104 ]

In cases where runtime services are not supported or have been disabled,
the runtime services workqueue will never have been allocated.

Do not try to destroy the workqueue unconditionally in the unlikely
event that EFI initialisation fails to avoid dereferencing a NULL
pointer.

Fixes: 98086df8b70c ("efi: add missed destroy_workqueue when efisubsys_init fails")
Cc: stable@vger.kernel.org
Cc: Li Heng &lt;liheng40@huawei.com&gt;
Signed-off-by: Johan Hovold &lt;johan+linaro@kernel.org&gt;
Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>firmware: coreboot: Register bus in module init</title>
<updated>2022-12-08T10:23:00+00:00</updated>
<author>
<name>Brian Norris</name>
<email>briannorris@chromium.org</email>
</author>
<published>2022-10-20T01:10:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7d08b4eba1e1f5e125eba987054d301c2e7ff8d6'/>
<id>7d08b4eba1e1f5e125eba987054d301c2e7ff8d6</id>
<content type='text'>
[ Upstream commit 65946690ed8d972fdb91a74ee75ac0f0f0d68321 ]

The coreboot_table driver registers a coreboot bus while probing a
"coreboot_table" device representing the coreboot table memory region.
Probing this device (i.e., registering the bus) is a dependency for the
module_init() functions of any driver for this bus (e.g.,
memconsole-coreboot.c / memconsole_driver_init()).

With synchronous probe, this dependency works OK, as the link order in
the Makefile ensures coreboot_table_driver_init() (and thus,
coreboot_table_probe()) completes before a coreboot device driver tries
to add itself to the bus.

With asynchronous probe, however, coreboot_table_probe() may race with
memconsole_driver_init(), and so we're liable to hit one of these two:

1. coreboot_driver_register() eventually hits "[...] the bus was not
   initialized.", and the memconsole driver fails to register; or
2. coreboot_driver_register() gets past #1, but still races with
   bus_register() and hits some other undefined/crashing behavior (e.g.,
   in driver_find() [1])

We can resolve this by registering the bus in our initcall, and only
deferring "device" work (scanning the coreboot memory region and
creating sub-devices) to probe().

[1] Example failure, using 'driver_async_probe=*' kernel command line:

[    0.114217] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
...
[    0.114307] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.1.0-rc1 #63
[    0.114316] Hardware name: Google Scarlet (DT)
...
[    0.114488] Call trace:
[    0.114494]  _raw_spin_lock+0x34/0x60
[    0.114502]  kset_find_obj+0x28/0x84
[    0.114511]  driver_find+0x30/0x50
[    0.114520]  driver_register+0x64/0x10c
[    0.114528]  coreboot_driver_register+0x30/0x3c
[    0.114540]  memconsole_driver_init+0x24/0x30
[    0.114550]  do_one_initcall+0x154/0x2e0
[    0.114560]  do_initcall_level+0x134/0x160
[    0.114571]  do_initcalls+0x60/0xa0
[    0.114579]  do_basic_setup+0x28/0x34
[    0.114588]  kernel_init_freeable+0xf8/0x150
[    0.114596]  kernel_init+0x2c/0x12c
[    0.114607]  ret_from_fork+0x10/0x20
[    0.114624] Code: 5280002b 1100054a b900092a f9800011 (885ffc01)
[    0.114631] ---[ end trace 0000000000000000 ]---

Fixes: b81e3140e412 ("firmware: coreboot: Make bus registration symmetric")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Brian Norris &lt;briannorris@chromium.org&gt;
Reviewed-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Link: https://lore.kernel.org/r/20221019180934.1.If29e167d8a4771b0bf4a39c89c6946ed764817b9@changeid
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@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 65946690ed8d972fdb91a74ee75ac0f0f0d68321 ]

The coreboot_table driver registers a coreboot bus while probing a
"coreboot_table" device representing the coreboot table memory region.
Probing this device (i.e., registering the bus) is a dependency for the
module_init() functions of any driver for this bus (e.g.,
memconsole-coreboot.c / memconsole_driver_init()).

With synchronous probe, this dependency works OK, as the link order in
the Makefile ensures coreboot_table_driver_init() (and thus,
coreboot_table_probe()) completes before a coreboot device driver tries
to add itself to the bus.

With asynchronous probe, however, coreboot_table_probe() may race with
memconsole_driver_init(), and so we're liable to hit one of these two:

1. coreboot_driver_register() eventually hits "[...] the bus was not
   initialized.", and the memconsole driver fails to register; or
2. coreboot_driver_register() gets past #1, but still races with
   bus_register() and hits some other undefined/crashing behavior (e.g.,
   in driver_find() [1])

We can resolve this by registering the bus in our initcall, and only
deferring "device" work (scanning the coreboot memory region and
creating sub-devices) to probe().

[1] Example failure, using 'driver_async_probe=*' kernel command line:

[    0.114217] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
...
[    0.114307] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.1.0-rc1 #63
[    0.114316] Hardware name: Google Scarlet (DT)
...
[    0.114488] Call trace:
[    0.114494]  _raw_spin_lock+0x34/0x60
[    0.114502]  kset_find_obj+0x28/0x84
[    0.114511]  driver_find+0x30/0x50
[    0.114520]  driver_register+0x64/0x10c
[    0.114528]  coreboot_driver_register+0x30/0x3c
[    0.114540]  memconsole_driver_init+0x24/0x30
[    0.114550]  do_one_initcall+0x154/0x2e0
[    0.114560]  do_initcall_level+0x134/0x160
[    0.114571]  do_initcalls+0x60/0xa0
[    0.114579]  do_basic_setup+0x28/0x34
[    0.114588]  kernel_init_freeable+0xf8/0x150
[    0.114596]  kernel_init+0x2c/0x12c
[    0.114607]  ret_from_fork+0x10/0x20
[    0.114624] Code: 5280002b 1100054a b900092a f9800011 (885ffc01)
[    0.114631] ---[ end trace 0000000000000000 ]---

Fixes: b81e3140e412 ("firmware: coreboot: Make bus registration symmetric")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Brian Norris &lt;briannorris@chromium.org&gt;
Reviewed-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Link: https://lore.kernel.org/r/20221019180934.1.If29e167d8a4771b0bf4a39c89c6946ed764817b9@changeid
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>firmware: google: Release devices before unregistering the bus</title>
<updated>2022-12-08T10:23:00+00:00</updated>
<author>
<name>Patrick Rudolph</name>
<email>patrick.rudolph@9elements.com</email>
</author>
<published>2019-11-18T10:19:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a2012335aa537c61b22dd01ce7e5eb3d0a2a1b74'/>
<id>a2012335aa537c61b22dd01ce7e5eb3d0a2a1b74</id>
<content type='text'>
[ Upstream commit cae0970ee9c4527f189aac378c50e2f0ed020418 ]

Fix a bug where the kernel module can't be loaded after it has been
unloaded as the devices are still present and conflicting with the
to be created coreboot devices.

Signed-off-by: Patrick Rudolph &lt;patrick.rudolph@9elements.com&gt;
Link: https://lore.kernel.org/r/20191118101934.22526-2-patrick.rudolph@9elements.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Stable-dep-of: 65946690ed8d ("firmware: coreboot: Register bus in module init")
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 cae0970ee9c4527f189aac378c50e2f0ed020418 ]

Fix a bug where the kernel module can't be loaded after it has been
unloaded as the devices are still present and conflicting with the
to be created coreboot devices.

Signed-off-by: Patrick Rudolph &lt;patrick.rudolph@9elements.com&gt;
Link: https://lore.kernel.org/r/20191118101934.22526-2-patrick.rudolph@9elements.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Stable-dep-of: 65946690ed8d ("firmware: coreboot: Register bus in module init")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efi: random: reduce seed size to 32 bytes</title>
<updated>2022-11-10T16:57:55+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ardb@kernel.org</email>
</author>
<published>2022-10-20T08:39:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fee896d4534fddff9476c95e6f244b70f5772ec1'/>
<id>fee896d4534fddff9476c95e6f244b70f5772ec1</id>
<content type='text'>
commit 161a438d730dade2ba2b1bf8785f0759aba4ca5f upstream.

We no longer need at least 64 bytes of random seed to permit the early
crng init to complete. The RNG is now based on Blake2s, so reduce the
EFI seed size to the Blake2s hash size, which is sufficient for our
purposes.

While at it, drop the READ_ONCE(), which was supposed to prevent size
from being evaluated after seed was unmapped. However, this cannot
actually happen, so READ_ONCE() is unnecessary here.

Cc: &lt;stable@vger.kernel.org&gt; # v4.14+
Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Reviewed-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Acked-by: Ilias Apalodimas &lt;ilias.apalodimas@linaro.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 161a438d730dade2ba2b1bf8785f0759aba4ca5f upstream.

We no longer need at least 64 bytes of random seed to permit the early
crng init to complete. The RNG is now based on Blake2s, so reduce the
EFI seed size to the Blake2s hash size, which is sufficient for our
purposes.

While at it, drop the READ_ONCE(), which was supposed to prevent size
from being evaluated after seed was unmapped. However, this cannot
actually happen, so READ_ONCE() is unnecessary here.

Cc: &lt;stable@vger.kernel.org&gt; # v4.14+
Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Reviewed-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Acked-by: Ilias Apalodimas &lt;ilias.apalodimas@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efi: libstub: drop pointless get_memory_map() call</title>
<updated>2022-10-26T11:23:00+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ardb@kernel.org</email>
</author>
<published>2022-09-15T17:00:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=96e2e21284ca4b1153fbc71811a3022ffa2850e5'/>
<id>96e2e21284ca4b1153fbc71811a3022ffa2850e5</id>
<content type='text'>
commit d80ca810f096ff66f451e7a3ed2f0cd9ef1ff519 upstream.

Currently, the non-x86 stub code calls get_memory_map() redundantly,
given that the data it returns is never used anywhere. So drop the call.

Cc: &lt;stable@vger.kernel.org&gt; # v4.14+
Fixes: 24d7c494ce46 ("efi/arm-stub: Round up FDT allocation to mapping size")
Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
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<pre>
commit d80ca810f096ff66f451e7a3ed2f0cd9ef1ff519 upstream.

Currently, the non-x86 stub code calls get_memory_map() redundantly,
given that the data it returns is never used anywhere. So drop the call.

Cc: &lt;stable@vger.kernel.org&gt; # v4.14+
Fixes: 24d7c494ce46 ("efi/arm-stub: Round up FDT allocation to mapping size")
Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
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</content>
</entry>
<entry>
<title>firmware: google: Test spinlock on panic path to avoid lockups</title>
<updated>2022-10-26T11:22:40+00:00</updated>
<author>
<name>Guilherme G. Piccoli</name>
<email>gpiccoli@igalia.com</email>
</author>
<published>2022-09-09T20:07:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c969316eeefb0726552c89ae96ea0de56604ccbd'/>
<id>c969316eeefb0726552c89ae96ea0de56604ccbd</id>
<content type='text'>
[ Upstream commit 3e081438b8e639cc76ef1a5ce0c1bd8a154082c7 ]

Currently the gsmi driver registers a panic notifier as well as
reboot and die notifiers. The callbacks registered are called in
atomic and very limited context - for instance, panic disables
preemption and local IRQs, also all secondary CPUs (not executing
the panic path) are shutdown.

With that said, taking a spinlock in this scenario is a dangerous
invitation for lockup scenarios. So, fix that by checking if the
spinlock is free to acquire in the panic notifier callback - if not,
bail-out and avoid a potential hang.

Fixes: 74c5b31c6618 ("driver: Google EFI SMI")
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Cc: David Gow &lt;davidgow@google.com&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Julius Werner &lt;jwerner@chromium.org&gt;
Cc: Petr Mladek &lt;pmladek@suse.com&gt;
Reviewed-by: Evan Green &lt;evgreen@chromium.org&gt;
Signed-off-by: Guilherme G. Piccoli &lt;gpiccoli@igalia.com&gt;
Link: https://lore.kernel.org/r/20220909200755.189679-1-gpiccoli@igalia.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
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<pre>
[ Upstream commit 3e081438b8e639cc76ef1a5ce0c1bd8a154082c7 ]

Currently the gsmi driver registers a panic notifier as well as
reboot and die notifiers. The callbacks registered are called in
atomic and very limited context - for instance, panic disables
preemption and local IRQs, also all secondary CPUs (not executing
the panic path) are shutdown.

With that said, taking a spinlock in this scenario is a dangerous
invitation for lockup scenarios. So, fix that by checking if the
spinlock is free to acquire in the panic notifier callback - if not,
bail-out and avoid a potential hang.

Fixes: 74c5b31c6618 ("driver: Google EFI SMI")
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Cc: David Gow &lt;davidgow@google.com&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Julius Werner &lt;jwerner@chromium.org&gt;
Cc: Petr Mladek &lt;pmladek@suse.com&gt;
Reviewed-by: Evan Green &lt;evgreen@chromium.org&gt;
Signed-off-by: Guilherme G. Piccoli &lt;gpiccoli@igalia.com&gt;
Link: https://lore.kernel.org/r/20220909200755.189679-1-gpiccoli@igalia.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
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