Message ID | 20200124200820.18272-1-f.fainelli@gmail.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | [stable,4.9] arm64: kpti: Whitelist Cortex-A CPUs that don't implement the CSV3 field | expand |
On Fri, Jan 24, 2020 at 12:08:20PM -0800, Florian Fainelli wrote: > From: Will Deacon <will.deacon@arm.com> > > commit 2a355ec25729053bb9a1a89b6c1d1cdd6c3b3fb1 upstream. > > While the CSV3 field of the ID_AA64_PFR0 CPU ID register can be checked > to see if a CPU is susceptible to Meltdown and therefore requires kpti > to be enabled, existing CPUs do not implement this field. > > We therefore whitelist all unaffected Cortex-A CPUs that do not implement > the CSV3 field. > > Signed-off-by: Will Deacon <will.deacon@arm.com> > [florian: adjust whilelist location and table to stable-4.9.y] > Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Thanks for the backport, now applied. greg k-h
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 9a8e45dc36bd..8cf001baee21 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -789,6 +789,11 @@ static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry, switch (read_cpuid_id() & MIDR_CPU_MODEL_MASK) { case MIDR_CAVIUM_THUNDERX2: case MIDR_BRCM_VULCAN: + case MIDR_CORTEX_A53: + case MIDR_CORTEX_A55: + case MIDR_CORTEX_A57: + case MIDR_CORTEX_A72: + case MIDR_CORTEX_A73: return false; }