kernel/linux.git/drivers/acpi, branch v5.15.212

ACPI: NFIT: core: Fix acpi_nfit_init() error cleanup

2026-07-24T13:51:56+00:00

[ Upstream commit 38bf27511ef41bffebd157ec3eba41fc89ba59cd ] If acpi_nfit_init() fails after adding the acpi_desc object to the acpi_descs list, that object is never removed from that list because the acpi_nfit_shutdown() devm action is not added for the NFIT device in that case. Next, the acpi_nfit_init() failure causes acpi_nfit_probe() to fail, the acpi_desc object is freed, and a dangling pointer is left behind in the acpi_descs. Any subsequent ACPI Machine Check Exception will trigger nfit_handle_mce() which iterates over acpi_descs and so a use-after-free will occur. Moreover, if acpi_nfit_probe() returns 0 after installing a notify handler for the NFIT device and without allocating the acpi_desc object and setting the NFIT device's driver data pointer, the acpi_desc object will be allocated by acpi_nfit_update_notify() and acpi_nfit_init() will be called to initialize it. Regardless of whether or not acpi_nfit_init() fails in that case, the acpi_nfit_shutdown() devm action is not added for the NFIT device and acpi_desc is never removed from the acpi_descs list. If the acpi_desc object is freed subsequently on driver removal, any subsequent ACPI MCE will lead to a use-after-free like in the previous case. To address the first issue mentioned above, make acpi_nfit_probe() call acpi_nfit_shutdown() directly on acpi_nfit_init() failures and to address the other one, add a remove callback to the driver and make it call acpi_nfit_shutdown(). Also, since it is now possible to pass NULL to acpi_nfit_shutdown() or the acpi_desc object passed to it may not have been initialized, add checks against NULL for acpi_desc and its nvdimm_bus field to that function and make acpi_nfit_unregister() clear the latter after unregistering the NVDIMM bus. Fixes: a61fe6f7902e ("nfit, tools/testing/nvdimm: unify common init for acpi_nfit_desc") Fixes: fbabd829fe76 ("acpi, nfit: fix module unload vs workqueue shutdown race") Signed-off-by: Rafael J. Wysocki Cc: All applicable Reviewed-by: Dave Jiang Link: https://patch.msgid.link/1963615.tdWV9SEqCh@rafael.j.wysocki Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

ACPI: CPPC: Suppress UBSAN warning caused by field misuse

2026-07-24T13:51:56+00:00

[ Upstream commit 1b1acf2dada0cc3931bb2cb9ff8832edfbee46a1 ] The definition of reg->access_width changes depending on the reg->space_id type. Type ACPI_ADR_SPACE_PLATFORM_COMM uses access_width to indicate the PCC region, which can result in a UBSAN if the value is greater than 4. For example: UBSAN: shift-out-of-bounds in drivers/acpi/cppc_acpi.c:1090:9 shift exponent 32 is too large for 32-bit type 'int' CPU: 61 UID: 0 PID: 1220 Comm: (udev-worker) Not tainted 7.0.10-201.fc44.aarch64 #1 PREEMPT(lazy) Hardware name: To be filled by O.E.M. Call trace: ...(trimming) ubsan_epilogue+0x10/0x48 __ubsan_handle_shift_out_of_bounds+0xdc/0x1e0 cpc_write+0x4d0/0x670 cppc_set_perf+0x18c/0x490 cppc_cpufreq_cpu_init+0x1c8/0x380 [cppc_cpufreq] ... (trimming) Lets fix this by validating the region type, as well as whether access_width has a value. Then since we are returning bit_width directly for ACPI_ADR_SPACE_PLATFORM_COMM, drop the code correcting the size. Fixes: 2f4a4d63a193 ("ACPI: CPPC: Use access_width over bit_width for system memory accesses") Signed-off-by: Jeremy Linton Tested-by: Jarred White Reviewed-by: Jarred White Reviewed-by: Easwar Hariharan Cc: All applicable Link: https://patch.msgid.link/20260601235808.1113137-1-jeremy.linton@arm.com Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

ACPI: resource: Amend kernel-doc style

2026-07-24T13:51:39+00:00

[ Upstream commit 78ad5c7722b7bed9d35ffc5b45eb0f12e2c22fee ] The functions are referred as func() in the kernel-doc. The % (percent) character makes the rendering for constants as described in the respective documentation. Amend all these. Fixes: 8e345c991c8c ("ACPI: Centralized processing of ACPI device resources") Signed-off-by: Andy Shevchenko Link: https://patch.msgid.link/20260617090555.2648709-1-andriy.shevchenko@linux.intel.com Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

ACPI: IPMI: Fix message kref handling on dead device

2026-07-24T13:51:33+00:00

[ Upstream commit 63320db6a5d84ec3fed8b3d36ba5244d07ddd108 ] acpi_ipmi_space_handler() takes an extra reference on tx_msg before checking whether the selected IPMI device is dead. The reference belongs to the tx_msg_list entry and is normally dropped by ipmi_cancel_tx_msg() or ipmi_flush_tx_msg() after the message is removed from the list. On the dead-device path, the message has not been queued yet, but the error path still calls ipmi_msg_release() directly. That bypasses kref_put() and frees tx_msg while the queued-message reference is still recorded in the kref count. Take the queued-message reference only after the dead-device check succeeds, immediately before adding tx_msg to the list. Fixes: 7b9844772237 ("ACPI / IPMI: Add reference counting for ACPI IPMI transfers") Signed-off-by: Yuho Choi Link: https://patch.msgid.link/20260603163108.2149359-1-dbgh9129@gmail.com Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

ACPI: video: force native backlight on HP OMEN 16 (8A44)

2026-06-01T15:35:19+00:00

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 Signed-off-by: Shivam Kalra Link: https://patch.msgid.link/20260426-omen-16-backlight-fix-v1-1-62364f268ea6@zohomail.in Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

ACPI: CPPC: Fix related_cpus inconsistency during CPU hotplug

2026-06-01T15:35:19+00:00

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->related_cpus: 220-221, policy->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->shared_cpu_map, policy->cpus, and related_cpus has only CPU 220. cpufreq: CPU: 220, policy->related_cpus: 220, policy->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->related_cpus = 220 after step 3, so CPU 221 is not in policy->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->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 & bash test.sh 221 & The test.sh is as below: while true do echo 0 > /sys/devices/system/cpu/cpu${1}/online sleep 0.5 cat /sys/devices/system/cpu/cpu${1}/cpufreq/related_cpus echo 1 > /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 Fixes: 56eb0c0ed345 ("ACPI: CPPC: Fix remaining for_each_possible_cpu() to use online CPUs") Co-developed-by: Sean Kelley Signed-off-by: Sean Kelley Signed-off-by: Jinjie Ruan [ rjw: Changelog edits ] Link: https://patch.msgid.link/20260417040112.3727756-1-ruanjinjie@huawei.com Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

ACPI: scan: Use acpi_dev_put() in object add error paths

2026-06-01T15:35:19+00:00

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 Signed-off-by: Guangshuo Li Link: https://patch.msgid.link/20260413135343.2884481-1-lgs201920130244@gmail.com Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

ACPI: EC: Fix ECDT probe ordering issues

2026-04-18T08:33:26+00:00

[ 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 Signed-off-by: Hans de Goede Signed-off-by: Rafael J. Wysocki Stable-dep-of: f6484cadbcaf ("ACPI: EC: clean up handlers on probe failure in acpi_ec_setup()") Signed-off-by: Sasha Levin

ACPI: EC: Fix EC address space handler unregistration

2026-04-18T08:33:26+00:00

[ 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 Signed-off-by: Hans de Goede Signed-off-by: Rafael J. Wysocki Stable-dep-of: f6484cadbcaf ("ACPI: EC: clean up handlers on probe failure in acpi_ec_setup()") Signed-off-by: Sasha Levin

ACPICA: Allow address_space_handler Install and _REG execution as 2 separate steps

2026-04-18T08:33:26+00:00

[ 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 Signed-off-by: Hans de Goede Signed-off-by: Rafael J. Wysocki Stable-dep-of: f6484cadbcaf ("ACPI: EC: clean up handlers on probe failure in acpi_ec_setup()") Signed-off-by: Sasha Levin