From: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
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@xxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Andre Przywara <andre.przywara@xxxxxxx>
Reviewed-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Signed-off-by: Will Deacon <will.deacon@xxxxxxx>
[ Viresh: Resolved rebase conflict ]
Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
---
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)
--
2.21.0.rc0.269.g1a574e7a288b
