]> git.ipfire.org Git - thirdparty/linux.git/commit
ACPI: CPPC: Fix missing PCC check for guaranteed_perf
authorPengjie Zhang <zhangpengjie2@huawei.com>
Wed, 10 Dec 2025 13:22:27 +0000 (21:22 +0800)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Mon, 15 Dec 2025 11:56:46 +0000 (12:56 +0100)
commit6ea3a44cef28add2d93b1ef119d84886cb1e3c9b
tree552e93fc2dbcb011b88f4ab0b0cfe0b2ac3d6c35
parent8f0b4cce4481fb22653697cced8d0d04027cb1e8
ACPI: CPPC: Fix missing PCC check for guaranteed_perf

The current implementation overlooks the 'guaranteed_perf'
register in this check.

If the Guaranteed Performance register is located in the PCC
subspace, the function currently attempts to read it without
acquiring the lock and without sending the CMD_READ doorbell
to the firmware. This can result in reading stale data.

Fixes: 29523f095397 ("ACPI / CPPC: Add support for guaranteed performance")
Signed-off-by: Pengjie Zhang <zhangpengjie2@huawei.com>
Cc: 4.20+ <stable@vger.kernel.org> # 4.20+
[ rjw: Subject and changelog edits ]
Link: https://patch.msgid.link/20251210132227.1988380-1-zhangpengjie2@huawei.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
drivers/acpi/cppc_acpi.c