diff options
| author | Suzuki K Poulose <suzuki.poulose@arm.com> | 2018-03-26 15:12:45 +0100 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2018-03-26 18:01:42 +0100 |
| commit | be5b299830c63ed76e0357473c4218c85fb388b3 (patch) | |
| tree | 9b64409be2dc85d787b6d7224d3bcb4cb235aa18 /arch/arm64/kernel/cpufeature.c | |
| parent | 1df310505d6d544802016f6bae49aab836ae8510 (diff) | |
arm64: capabilities: Add support for checks based on a list of MIDRs
Add helpers for detecting an errata on list of midr ranges
of affected CPUs, with the same work around.
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/arm64/kernel/cpufeature.c')
| -rw-r--r-- | arch/arm64/kernel/cpufeature.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 17132a10a3db..86e2b987a08e 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -882,6 +882,11 @@ static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */ static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry, int scope) { + /* List of CPUs that are not vulnerable and don't need KPTI */ + static const struct midr_range kpti_safe_list[] = { + MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2), + MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN), + }; char const *str = "command line option"; /* @@ -906,11 +911,8 @@ static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry, return true; /* Don't force KPTI for CPUs that are not vulnerable */ - switch (read_cpuid_id() & MIDR_CPU_MODEL_MASK) { - case MIDR_CAVIUM_THUNDERX2: - case MIDR_BRCM_VULCAN: + if (is_midr_in_range_list(read_cpuid_id(), kpti_safe_list)) return false; - } /* Defer to CPU feature registers */ return !has_cpuid_feature(entry, scope); |