From: Suzuki K Poulose suzuki.poulose@arm.com
commit 6a6efbb45b7d95c84840010095367eb06a64f342 upstream.
CPU Errata work arounds are detected and applied to the kernel code at boot time and the data is then freed up. If a new hotplugged CPU requires a work around which was not applied at boot time, there is nothing we can do but simply fail the booting.
Cc: Will Deacon will.deacon@arm.com Cc: Mark Rutland mark.rutland@arm.com Cc: Andre Przywara andre.przywara@arm.com Reviewed-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com Signed-off-by: Will Deacon will.deacon@arm.com [ Viresh: Resolved rebase conflict ] Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- arch/arm64/include/asm/cpufeature.h | 2 ++ arch/arm64/kernel/cpu_errata.c | 20 ++++++++++++++++++++ arch/arm64/kernel/cpufeature.c | 2 ++ 3 files changed, 24 insertions(+)
diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index 4c31e14c0f0e..dd1aab8e52aa 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -173,6 +173,8 @@ void update_cpu_capabilities(const struct arm64_cpu_capabilities *caps, const char *info); void check_local_cpu_errata(void);
+void verify_local_cpu_errata(void); + #ifdef CONFIG_HOTPLUG_CPU void verify_local_cpu_capabilities(void); #else diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c index 0971d80d3623..a3567881c01b 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -116,6 +116,26 @@ const struct arm64_cpu_capabilities arm64_errata[] = { } };
+/* + * The CPU Errata work arounds are detected and applied at boot time + * and the related information is freed soon after. If the new CPU requires + * an errata not detected at boot, fail this CPU. + */ +void verify_local_cpu_errata(void) +{ + const struct arm64_cpu_capabilities *caps = arm64_errata; + + for (; caps->matches; caps++) + if (!cpus_have_cap(caps->capability) && + caps->matches(caps, SCOPE_LOCAL_CPU)) { + pr_crit("CPU%d: Requires work around for %s, not detected" + " at boot time\n", + smp_processor_id(), + caps->desc ? : "an erratum"); + cpu_die_early(); + } +} + void check_local_cpu_errata(void) { update_cpu_capabilities(arm64_errata, "enabling workaround for"); diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index a0273cd8be51..9a4b638b1c18 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -872,6 +872,8 @@ void verify_local_cpu_capabilities(void) if (!sys_caps_initialised) return;
+ verify_local_cpu_errata(); + caps = arm64_features; for (i = 0; caps[i].matches; i++) { if (!cpus_have_cap(caps[i].capability) || !caps[i].sys_reg)