<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/drivers/acpi, branch v5.15.209</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v5.15.209</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v5.15.209'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2026-06-01T15:35:19+00:00</updated>
<entry>
<title>ACPI: video: force native backlight on HP OMEN 16 (8A44)</title>
<updated>2026-06-01T15:35:19+00:00</updated>
<author>
<name>Shivam Kalra</name>
<email>shivamkalra98@zohomail.in</email>
</author>
<published>2026-04-26T14:08:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=8d79505d1b14223521b63d9e7755f7e7def2989b'/>
<id>urn:sha1:8d79505d1b14223521b63d9e7755f7e7def2989b</id>
<content type='text'>
commit 4b506ea5351a1f5937ac632a4a5c35f6f796cc41 upstream.

The HP OMEN 16 Gaming Laptop (board name 8A44) has a mux-less hybrid
GPU configuration with AMD Rembrandt (Radeon 680M) and NVIDIA GA104
(RTX 3070 Ti). The internal eDP panel is wired to the AMD iGPU.

When Nouveau loads without GSP firmware, the ACPI video backlight
device (acpi_video0) gets registered alongside the native AMD
backlight (amdgpu_bl2). In this state, writes to amdgpu_bl2 update
the software brightness value but fail to change the physical panel
brightness.

Force native backlight to prevent acpi_video0 from registering.
Confirmed that booting with acpi_backlight=native resolves the
issue.

Cc: All applicable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Shivam Kalra &lt;shivamkalra98@zohomail.in&gt;
Link: https://patch.msgid.link/20260426-omen-16-backlight-fix-v1-1-62364f268ea6@zohomail.in
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>ACPI: CPPC: Fix related_cpus inconsistency during CPU hotplug</title>
<updated>2026-06-01T15:35:19+00:00</updated>
<author>
<name>Jinjie Ruan</name>
<email>ruanjinjie@huawei.com</email>
</author>
<published>2026-04-17T04:01:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=14e43d92410167fd0ede4a0bd81b58216014826a'/>
<id>urn:sha1:14e43d92410167fd0ede4a0bd81b58216014826a</id>
<content type='text'>
commit 75141a770f4f8225d316f6c7e146723a32e9720e upstream.

When concurrently bringing up and down two SMT threads of a physical
core, many warning call traces occur as below:

The issue timeline is as follows:

 1. When the system starts,
    cpufreq: CPU: 220, policy-&gt;related_cpus: 220-221, policy-&gt;cpus: 220-221

 2. Offline CPU 220 and CPU 221.

 3. Online CPU 220
    - CPU 221 is now offline, as acpi_get_psd_map() use
      for_each_online_cpu(), so the cpu_data-&gt;shared_cpu_map,
      policy-&gt;cpus, and related_cpus has only CPU 220.

    cpufreq: CPU: 220, policy-&gt;related_cpus: 220, policy-&gt;cpus: 220

 4. Offline CPU 220

 5. Online CPU 221, the below call trace occurs:
    - Since CPU 220 and CPU 221 share one policy, and
      policy-&gt;related_cpus = 220 after step 3, so CPU 221
      is not in policy-&gt;related_cpus but
      per_cpu(cpufreq_cpu_data, cpu221) is not NULL.

After reverting commit 56eb0c0ed345 ("ACPI: CPPC: Fix remaining
for_each_possible_cpu() to use online CPUs"), the issue disappeared.

The _PSD (P-State Dependency) defines the hardware-level dependency of
frequency control across CPU cores. Since this relationship is a physical
attribute of the hardware topology, it remains constant regardless of the
online or offline status of the CPUs.

Using for_each_online_cpu() in acpi_get_psd_map() is problematic. If a
CPU is offline, it will be excluded from the shared_cpu_map.
Consequently, if that CPU is brought online later, the kernel will fail
to recognize it as part of any shared frequency domain.

Switch back to for_each_possible_cpu() to ensure that all cores defined
in the ACPI tables are correctly mapped into their respective performance
domains from the start. This aligns with the logic of policy-&gt;related_cpus,
which must encompass all potentially available cores in the domain to
prevent logic gaps during CPU hotplug operations.

To resolve the original issue regarding the "nosmt" or "nosmt=force"
boot parameter, as send_pcc_cmd() function already does if (!desc)
continue, so reverting that loop back to for_each_possible_cpu() is ok,
only need to change the match_cpc_ptr NULL case in acpi_get_psd_map() to
continue as Sean suggested.

How to reproduce, on arm64 machine with SMT support which use acpi cppc
cpufreq driver:

	bash test.sh 220 &amp; bash test.sh 221 &amp;

	The test.sh is as below:
		while true
			do
			echo 0 &gt; /sys/devices/system/cpu/cpu${1}/online
			sleep 0.5
			cat /sys/devices/system/cpu/cpu${1}/cpufreq/related_cpus
			echo 1 &gt;  /sys/devices/system/cpu/cpu${1}/online
			cat /sys/devices/system/cpu/cpu${1}/cpufreq/related_cpus
		done

	CPU: 221 PID: 1119 Comm: cpuhp/221 Kdump: loaded Not tainted 6.6.0debug+ #5
	Hardware name: To be filled by O.E.M. S920X20/BC83AMDA01-7270Z, BIOS 20.39 09/04/2024
	pstate: a1400009 (NzCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
	pc : cpufreq_online+0x8ac/0xa90
	lr : cpuhp_cpufreq_online+0x18/0x30
	sp : ffff80008739bce0
	x29: ffff80008739bce0 x28: 0000000000000000 x27: ffff28400ca32200
	x26: 0000000000000000 x25: 0000000000000003 x24: ffffd483503ff000
	x23: ffffd483504051a0 x22: ffffd48350024a00 x21: 00000000000000dd
	x20: 000000000000001d x19: ffff28400ca32000 x18: 0000000000000000
	x17: 0000000000000020 x16: ffffd4834e6a3fc8 x15: 0000000000000020
	x14: 0000000000000008 x13: 0000000000000001 x12: 00000000ffffffff
	x11: 0000000000000040 x10: ffffd48350430728 x9 : ffffd4834f087c78
	x8 : 0000000000000001 x7 : ffff2840092bdf00 x6 : ffffd483504264f0
	x5 : ffffd48350405000 x4 : ffff283f7f95cc60 x3 : 0000000000000000
	x2 : ffff53bc2f94b000 x1 : 00000000000000dd x0 : 0000000000000000
	Call trace:
	 cpufreq_online+0x8ac/0xa90
	 cpuhp_cpufreq_online+0x18/0x30
	 cpuhp_invoke_callback+0x128/0x580
	 cpuhp_thread_fun+0x110/0x1b0
	 smpboot_thread_fn+0x140/0x190
	 kthread+0xec/0x100
	 ret_from_fork+0x10/0x20
	---[ end trace 0000000000000000 ]---

Cc: All applicable &lt;stable@vger.kernel.org&gt;
Fixes: 56eb0c0ed345 ("ACPI: CPPC: Fix remaining for_each_possible_cpu() to use online CPUs")
Co-developed-by: Sean Kelley &lt;skelley@nvidia.com&gt;
Signed-off-by: Sean Kelley &lt;skelley@nvidia.com&gt;
Signed-off-by: Jinjie Ruan &lt;ruanjinjie@huawei.com&gt;
[ rjw: Changelog edits ]
Link: https://patch.msgid.link/20260417040112.3727756-1-ruanjinjie@huawei.com
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>ACPI: scan: Use acpi_dev_put() in object add error paths</title>
<updated>2026-06-01T15:35:19+00:00</updated>
<author>
<name>Guangshuo Li</name>
<email>lgs201920130244@gmail.com</email>
</author>
<published>2026-04-13T13:53:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=432c15f39172ccd984e56baeafdc6db3460f9b96'/>
<id>urn:sha1:432c15f39172ccd984e56baeafdc6db3460f9b96</id>
<content type='text'>
commit 9c0acc169ac71535477caedea8315f7041c5f07c upstream.

After acpi_init_device_object(), the lifetime of struct acpi_device is
managed by the driver core through reference counting.

Both acpi_add_power_resource() and acpi_add_single_object() call
acpi_init_device_object() and then invoke acpi_device_add(). If that
fails, their error paths call the release callback directly instead of
dropping the device reference through acpi_dev_put().

This bypasses the normal device lifetime rules and frees the object
without releasing the reference acquired by device_initialize(), which
may lead to a refcount leak.

The issue was identified by a static analysis tool I developed and
confirmed by manual review.

Fix both error paths by using acpi_dev_put() and let the release
callback handle the final cleanup.

Fixes: 781d737c7466 ("ACPI: Drop power resources driver")
Fixes: 718fb0de8ff88 ("ACPI: fix NULL bug for HID/UID string")
Cc: All applicable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Guangshuo Li &lt;lgs201920130244@gmail.com&gt;
Link: https://patch.msgid.link/20260413135343.2884481-1-lgs201920130244@gmail.com
Signed-off-by: Rafael J. Wysocki &lt;rjw@rjwysocki.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>ACPI: EC: Fix ECDT probe ordering issues</title>
<updated>2026-04-18T08:33:26+00:00</updated>
<author>
<name>Hans de Goede</name>
<email>hdegoede@redhat.com</email>
</author>
<published>2022-12-08T14:23:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=80d62860eac51606983dc5156c6fe7aa899bdb09'/>
<id>urn:sha1:80d62860eac51606983dc5156c6fe7aa899bdb09</id>
<content type='text'>
[ Upstream commit ab4620f58d38206687b9f99d9d2cc1d5a2640985 ]

ACPI-2.0 says that the EC OpRegion handler must be available immediately
(like the standard default OpRegion handlers):

Quoting from the ACPI spec version 6.3: "6.5.4 _REG (Region) ...
2. OSPM must make Embedded Controller operation regions, accessed via
the Embedded Controllers described in ECDT, available before executing
any control method. These operation regions may become inaccessible
after OSPM runs _REG(EmbeddedControl, 0)."

So acpi_bus_init() calls acpi_ec_ecdt_probe(), which calls
acpi_install_address_space_handler() to install the EC's OpRegion
handler, early on.

This not only installs the OpRegion handler, but also calls the EC's
_REG method. The _REG method call is a problem because it may rely on
initialization done by the _INI methods of one of the PCI / _SB root devs,
see for example: https://bugzilla.kernel.org/show_bug.cgi?id=214899 .

Generally speaking _REG methods are executed when the ACPI-device they
are part of has a driver bound to it. Where as _INI methods must be
executed at table load time (according to the spec). The problem here
is that the early acpi_install_address_space_handler() call causes
the _REG handler to run too early.

To allow fixing this the ACPICA code now allows to split the OpRegion
handler installation and the executing of _REG into 2 separate steps.

This commit uses this ACPICA functionality to fix the EC probe ordering
by delaying the executing of _REG for ECDT described ECs till the matching
EC device in the DSDT gets parsed and acpi_ec_add() for it gets called.
This moves the calling of _REG for the EC on devices with an ECDT to
the same point in time where it is called on devices without an ECDT table.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=214899
Reported-and-tested-by: Johannes Penßel &lt;johannespenssel@posteo.net&gt;
Signed-off-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Stable-dep-of: f6484cadbcaf ("ACPI: EC: clean up handlers on probe failure in acpi_ec_setup()")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>ACPI: EC: Fix EC address space handler unregistration</title>
<updated>2026-04-18T08:33:26+00:00</updated>
<author>
<name>Hans de Goede</name>
<email>hdegoede@redhat.com</email>
</author>
<published>2022-12-08T14:23:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=08f5d5cbff5ef553cac354d2194f07a9d79dd2e3'/>
<id>urn:sha1:08f5d5cbff5ef553cac354d2194f07a9d79dd2e3</id>
<content type='text'>
[ Upstream commit a5072078dbfaa9d70130805766dfa34bbb7bf2a7 ]

When an ECDT table is present the EC address space handler gets registered
on the root node. So to unregister it properly the unregister call also
must be done on the root node.

Store the ACPI handle used for the acpi_install_address_space_handler()
call and use te same handle for the acpi_remove_address_space_handler()
call.

Reported-by: Rafael J. Wysocki &lt;rafael@kernel.org&gt;
Signed-off-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Stable-dep-of: f6484cadbcaf ("ACPI: EC: clean up handlers on probe failure in acpi_ec_setup()")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>ACPICA: Allow address_space_handler Install and _REG execution as 2 separate steps</title>
<updated>2026-04-18T08:33:26+00:00</updated>
<author>
<name>Hans de Goede</name>
<email>hdegoede@redhat.com</email>
</author>
<published>2022-12-08T14:23:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=870f9c647de54203f4c9ab9fb0c2922889c4dd08'/>
<id>urn:sha1:870f9c647de54203f4c9ab9fb0c2922889c4dd08</id>
<content type='text'>
[ Upstream commit 54c516aeb8b39eeae6450b7d8076d381568dca46 ]

ACPI-2.0 says that the EC op_region handler must be available immediately
(like the standard default op_region handlers):

Quoting from the ACPI spec version 6.3: "6.5.4 _REG (Region) ...
2. OSPM must make Embedded Controller operation regions, accessed via
the Embedded Controllers described in ECDT, available before executing
any control method. These operation regions may become inaccessible
after OSPM runs _REG(EmbeddedControl, 0)."

So the OS must probe the ECDT described EC and install the OpRegion handler
before calling acpi_enable_subsystem() and acpi_initialize_objects().

This is a problem because calling acpi_install_address_space_handler()
does not just install the op_region handler, it also runs the EC's _REG
method. This _REG method may rely on initialization done by the _INI
methods of one of the PCI / _SB root devices.

For the other early/default op_region handlers the op_region handler
install and the _REG execution is split into 2 separate steps:
1. acpi_ev_install_region_handlers(), called early from acpi_load_tables()
2. acpi_ev_initialize_op_regions(), called from acpi_initialize_objects()

To fix the EC op_region issue, add 2 bew functions:
1. acpi_install_address_space_handler_no_reg()
2. acpi_execute_reg_methods()
to allow doing things in 2 steps for other op_region handlers,
like the EC handler, too.

Note that the comment describing acpi_ev_install_region_handlers() even has
an alinea describing this problem. Using the new methods allows users
to avoid this problem.

Link: https://github.com/acpica/acpica/pull/786
Link: https://bugzilla.kernel.org/show_bug.cgi?id=214899
Reported-and-tested-by: Johannes Penßel &lt;johannespenssel@posteo.net&gt;
Signed-off-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Stable-dep-of: f6484cadbcaf ("ACPI: EC: clean up handlers on probe failure in acpi_ec_setup()")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>ACPI: processor: Fix previous acpi_processor_errata_piix4() fix</title>
<updated>2026-04-18T08:33:21+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2026-03-17T20:39:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=68408e8f9e366ad9850a66ac65cb569f13bf6cd4'/>
<id>urn:sha1:68408e8f9e366ad9850a66ac65cb569f13bf6cd4</id>
<content type='text'>
[ Upstream commit bf504b229cb8d534eccbaeaa23eba34c05131e25 ]

After commi f132e089fe89 ("ACPI: processor: Fix NULL-pointer dereference
in acpi_processor_errata_piix4()"), device pointers may be dereferenced
after dropping references to the device objects pointed to by them,
which may cause a use-after-free to occur.

Moreover, debug messages about enabling the errata may be printed
if the errata flags corresponding to them are unset.

Address all of these issues by moving message printing to the points
in the code where the errata flags are set.

Fixes: f132e089fe89 ("ACPI: processor: Fix NULL-pointer dereference in acpi_processor_errata_piix4()")
Reported-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
Closes: https://lore.kernel.org/linux-acpi/938e2206-def5-4b7a-9b2c-d1fd37681d8a@roeck-us.net/
Reviewed-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Link: https://patch.msgid.link/5975693.DvuYhMxLoT@rafael.j.wysocki
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>ACPI: OSL: fix __iomem type on return from acpi_os_map_generic_address()</title>
<updated>2026-04-18T08:33:13+00:00</updated>
<author>
<name>Ben Dooks</name>
<email>ben.dooks@codethink.co.uk</email>
</author>
<published>2026-03-11T10:58:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=4ee70a46a4196d4c51d93afd00ab20ecf7d12554'/>
<id>urn:sha1:4ee70a46a4196d4c51d93afd00ab20ecf7d12554</id>
<content type='text'>
[ Upstream commit 393815f57651101f1590632092986d1d5a3a41bd ]

The pointer returned from acpi_os_map_generic_address() is
tagged with __iomem, so make the rv it is returned to also
of void __iomem * type.

Fixes the following sparse warning:

drivers/acpi/osl.c:1686:20: warning: incorrect type in assignment (different address spaces)
drivers/acpi/osl.c:1686:20:    expected void *rv
drivers/acpi/osl.c:1686:20:    got void [noderef] __iomem *

Fixes: 6915564dc5a8 ("ACPI: OSL: Change the type of acpi_os_map_generic_address() return value")
Signed-off-by: Ben Dooks &lt;ben.dooks@codethink.co.uk&gt;
[ rjw: Subject tweak, added Fixes tag ]
Link: https://patch.msgid.link/20260311105835.463030-1-ben.dooks@codethink.co.uk
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>ACPI: OSI: Add DMI quirk for Acer Aspire One D255</title>
<updated>2026-04-18T08:33:11+00:00</updated>
<author>
<name>Sofia Schneider</name>
<email>sofia@schn.dev</email>
</author>
<published>2026-02-23T02:52:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=be40b0297634e4d032c2aa53aa33493768346492'/>
<id>urn:sha1:be40b0297634e4d032c2aa53aa33493768346492</id>
<content type='text'>
[ Upstream commit 5ede90206273ff156a778254f0f972a55e973c89 ]

The screen backlight turns off during boot (specifically during udev device
initialization) when returning true for _OSI("Windows 2009").

Analyzing the device's DSDT reveals that the firmware takes a different
code path when Windows 7 is reported, which leads to the backlight shutoff.
Add a DMI quirk to invoke dmi_disable_osi_win7 for this model.

Signed-off-by: Sofia Schneider &lt;sofia@schn.dev&gt;
Link: https://patch.msgid.link/20260223025240.518509-1-sofia@schn.dev
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>ACPI: PM: Save NVS memory on Lenovo G70-35</title>
<updated>2026-04-18T08:33:11+00:00</updated>
<author>
<name>Piotr Mazek</name>
<email>pmazek@outlook.com</email>
</author>
<published>2026-02-05T22:05:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=9cc7d9aa5dfd63fd1f501700160b073fa1cd2925'/>
<id>urn:sha1:9cc7d9aa5dfd63fd1f501700160b073fa1cd2925</id>
<content type='text'>
[ Upstream commit 023cd6d90f8aa2ef7b72d84be84a18e61ecebd64 ]

[821d6f0359b0614792ab8e2fb93b503e25a65079] prevented machines
produced later than 2012 from saving NVS region to accelerate S3.

Despite being made after 2012, Lenovo G70-35 still needs NVS memory
saving during S3. A quirk is introduced for this platform.

Signed-off-by: Piotr Mazek &lt;pmazek@outlook.com&gt;
[ rjw: Subject adjustment ]
Link: https://patch.msgid.link/GV2PPF3CD5B63CC2442EE3F76F8443EAD90D499A@GV2PPF3CD5B63CC.EURP251.PROD.OUTLOOK.COM
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
</feed>
