commit c0b15c25d25171db4b70cc0b7dbc1130ee94017d upstream The erratum 1024718 affects Cortex-A55 r0p0 to r2p0. However we apply the work around for r0p0 - r1p0. Unfortunately this won't be fixed for the future revisions for the CPU. Thus extend the work around for all versions of A55, to cover for r2p0 and any future revisions. Cc: stable@xxxxxxxxxxxxxxx # v5.4- Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Cc: James Morse <james.morse@xxxxxxx> Cc: Kunihiko Hayashi <hayashi.kunihiko@xxxxxxxxxxxxx> Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx> Link: https://lore.kernel.org/r/20210203230057.3961239-1-suzuki.poulose@xxxxxxx [will: Update Kconfig help text] Signed-off-by: Will Deacon <will@xxxxxxxxxx> Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx> --- arch/arm64/Kconfig | 2 +- arch/arm64/kernel/cpufeature.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index a0bc9bbb92f3..0ad21882aa04 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -489,7 +489,7 @@ config ARM64_ERRATUM_1024718 help This option adds a workaround for ARM Cortex-A55 Erratum 1024718. - Affected Cortex-A55 cores (r0p0, r0p1, r1p0) could cause incorrect + Affected Cortex-A55 cores (all versions) could cause incorrect update of the hardware dirty bit when the DBM/AP bits are updated without a break-before-make. The workaround is to disable the usage of hardware DBM locally on the affected cores. CPUs not affected by diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index f2ec84540414..79caab15ccbf 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -1092,7 +1092,7 @@ static bool cpu_has_broken_dbm(void) /* List of CPUs which have broken DBM support. */ static const struct midr_range cpus[] = { #ifdef CONFIG_ARM64_ERRATUM_1024718 - MIDR_RANGE(MIDR_CORTEX_A55, 0, 0, 1, 0), // A55 r0p0 -r1p0 + MIDR_ALL_VERSIONS(MIDR_CORTEX_A55), #endif {}, }; -- 2.24.1
