Commit 0cdbb920 authored by heppen's avatar heppen
Browse files

ACPI: CPPC: fix bug that causes the value written in cpc register to be wrong. 

mainline inclusion
from mainline-v6.13-rc1
commit 2388b266c9fcc7c9169ba85c7f9ebe325b7622d7
bugzilla: https://gitee.com/openeuler/kernel/issues/IB5JJG


CVE: NA

--------------------------------

With these codes, the value written in cpc register will be the result of
the OR operatiion on input value and prev_val. This will causes the value
to be wrong.

Signed-off-by: default avatarLifeng Zheng <zhenglifeng1@huawei.com>
parent 4e05c2f4

drivers/acpi/cppc_acpi.c

+0 −1
Original line number Diff line number Diff line
@@ -1142,7 +1142,6 @@ static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 val) 
			return -EFAULT;

		}

		val = MASK_VAL_WRITE(reg, prev_val, val);

		val |= prev_val;

	}



	switch (size) {