kernel/linux.git/drivers/acpi/acpi_processor.c, branch v6.1.168

ACPI: processor: Fix previous acpi_processor_errata_piix4() fix

2026-03-25T10:03:22+00:00

[ 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 Closes: https://lore.kernel.org/linux-acpi/938e2206-def5-4b7a-9b2c-d1fd37681d8a@roeck-us.net/ Reviewed-by: Guenter Roeck Signed-off-by: Rafael J. Wysocki Link: https://patch.msgid.link/5975693.DvuYhMxLoT@rafael.j.wysocki Signed-off-by: Sasha Levin

ACPI: processor: Fix NULL-pointer dereference in acpi_processor_errata_piix4()

2026-03-04T12:20:14+00:00

[ Upstream commit f132e089fe89cadc2098991f0a3cb05c3f824ac6 ] In acpi_processor_errata_piix4(), the pointer dev is first assigned an IDE device and then reassigned an ISA device: dev = pci_get_subsys(..., PCI_DEVICE_ID_INTEL_82371AB, ...); dev = pci_get_subsys(..., PCI_DEVICE_ID_INTEL_82371AB_0, ...); If the first lookup succeeds but the second fails, dev becomes NULL. This leads to a potential null-pointer dereference when dev_dbg() is called: if (errata.piix4.bmisx) dev_dbg(&dev->dev, ...); To prevent this, use two temporary pointers and retrieve each device independently, avoiding overwriting dev with a possible NULL value. Signed-off-by: Tuo Li [ rjw: Subject adjustment, added an empty code line ] Link: https://patch.msgid.link/20260111163214.202262-1-islituo@gmail.com Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

ACPI: processor: fix acpi_object initialization

2025-08-28T14:25:53+00:00

[ Upstream commit 13edf7539211d8f7d0068ce3ed143005f1da3547 ] Initialization of the local acpi_object in acpi_processor_get_info() only sets the first 4 bytes to zero and is thus incomplete. This is indicated by messages like: acpi ACPI0007:be: Invalid PBLK length [166288104] Fix this by initializing all 16 bytes of the processor member of that union. Signed-off-by: Sebastian Ott Link: https://patch.msgid.link/20250703124215.12522-1-sebott@redhat.com Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

ACPI: processor: Fix memory leaks in error paths of processor_add()

2024-09-12T09:10:28+00:00

[ Upstream commit 47ec9b417ed9b6b8ec2a941cd84d9de62adc358a ] If acpi_processor_get_info() returned an error, pr and the associated pr->throttling.shared_cpu_map were leaked. The unwind code was in the wrong order wrt to setup, relying on some unwind actions having no affect (clearing variables that were never set etc). That makes it harder to reason about so reorder and add appropriate labels to only undo what was actually set up in the first place. Acked-by: Rafael J. Wysocki Reviewed-by: Gavin Shan Signed-off-by: Jonathan Cameron Link: https://lore.kernel.org/r/20240529133446.28446-6-Jonathan.Cameron@huawei.com Signed-off-by: Catalin Marinas Signed-off-by: Sasha Levin

ACPI: processor: Return an error if acpi_processor_get_info() fails in processor_add()

2024-09-12T09:10:28+00:00

[ Upstream commit fadf231f0a06a6748a7fc4a2c29ac9ef7bca6bfd ] Rafael observed [1] that returning 0 from processor_add() will result in acpi_default_enumeration() being called which will attempt to create a platform device, but that makes little sense when the processor is known to be not available. So just return the error code from acpi_processor_get_info() instead. Link: https://lore.kernel.org/all/CAJZ5v0iKU8ra9jR+EmgxbuNm=Uwx2m1-8vn_RAZ+aCiUVLe3Pw@mail.gmail.com/ [1] Suggested-by: Rafael J. Wysocki Acked-by: Rafael J. Wysocki Reviewed-by: Gavin Shan Signed-off-by: Jonathan Cameron Link: https://lore.kernel.org/r/20240529133446.28446-5-Jonathan.Cameron@huawei.com Signed-off-by: Catalin Marinas Signed-off-by: Sasha Levin

ACPI: processor: Replace deprecated CPU-hotplug functions

2021-08-04T18:25:54+00:00

The functions cpu_hotplug_begin, cpu_hotplug_done, get_online_cpus() and put_online_cpus() have been deprecated during the CPU hotplug rework. They map directly to cpus_write_lock(), cpus_write_unlock, cpus_read_lock() and cpus_read_unlock(). Replace deprecated CPU-hotplug functions with the official version. The behavior remains unchanged. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Rafael J. Wysocki

Merge branch 'acpi-misc'

2021-04-26T15:04:41+00:00

* acpi-misc: ACPI: dock: fix some coding style issues ACPI: sysfs: fix some coding style issues ACPI: PM: add a missed blank line after declarations ACPI: custom_method: fix a coding style issue ACPI: CPPC: fix some coding style issues ACPI: button: fix some coding style issues ACPI: battery: fix some coding style issues ACPI: acpi_pad: add a missed blank line after declarations ACPI: LPSS: add a missed blank line after declarations ACPI: ipmi: remove useless return statement for void function ACPI: processor: fix some coding style issues ACPI: APD: fix a block comment align issue ACPI: AC: fix some coding style issues ACPI: fix various typos in comments

ACPI: processor: fix some coding style issues

2021-04-08T14:27:02+00:00

Fix some coding style issues reported by checkpatch.pl, including the following types: ERROR: code indent should use tabs where possible WARNING: Block comments use a trailing */ on a separate line WARNING: Missing a blank line after declarations WARNING: labels should not be indented Signed-off-by: Xiaofei Tan Signed-off-by: Rafael J. Wysocki

ACPI: processor: Get rid of ACPICA message printing

2021-03-08T15:51:19+00:00

The ACPI_DEBUG_PRINT() and ACPI_EXCEPTION() macros are used for message printing in the ACPICA code and they should not be used elsewhere. Special configuration (either kernel command line or sysfs-based) is needed to see the messages printed by them and the format of those messages is also special and convoluted. For this reason, replace all of the ACPI_DEBUG_PRINT() and ACPI_EXCEPTION() instances in the ACPI processor driver with corresponding dev_*(), acpi_handle_*() and pr_*() calls depending on the context in which they appear. Also drop the ACPI_PROCESSOR_COMPONENT definition that is not going to be necessary any more. Signed-off-by: Rafael J. Wysocki Reviewed-by: Hanjun Guo

ACPI: processor: remove comment regarding string _UID support

2020-10-16T16:11:27+00:00

ACPI 6.3 Errata A no longer allows _UID to return a string except for Itanium (for historical reasons) as stated in section 5.2.12: "From ACPI Specification 6.3 onward, all processor objects for all architectures except Itanium must now use Device() objects with an _HID of ACPI0007, and use only integer _UID values." Therefore, the "we don't handle string _UIDs yet" comment, which implies a missing feature, is redundant, so drop it. Signed-off-by: Alex Hung [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki