[PATCH 03/17] arm64: Allow checking of a CPU-local erratum

Marc Zyngier marc.zyngier at arm.com
Mon Mar 6 03:26:08 PST 2017

this_cpu_has_cap() only checks the feature array, and not the errata
one. In order to be able to check for a CPU-local erratum, allow it
to inspect the latter as well.

This is consistent with cpus_have_cap()'s behaviour, which includes
errata already.

Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
 arch/arm64/kernel/cpufeature.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index abda8e861865..6eb77ae99b79 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -1090,20 +1090,29 @@ static void __init setup_feature_capabilities(void)
  * Check if the current CPU has a given feature capability.
  * Should be called from non-preemptible context.
-bool this_cpu_has_cap(unsigned int cap)
+static bool __this_cpu_has_cap(const struct arm64_cpu_capabilities *cap_array,
+			       unsigned int cap)
 	const struct arm64_cpu_capabilities *caps;
 	if (WARN_ON(preemptible()))
 		return false;
-	for (caps = arm64_features; caps->desc; caps++)
+	for (caps = cap_array; caps->desc; caps++)
 		if (caps->capability == cap && caps->matches)
 			return caps->matches(caps, SCOPE_LOCAL_CPU);
 	return false;
+extern const struct arm64_cpu_capabilities arm64_errata[];
+bool this_cpu_has_cap(unsigned int cap)
+	return (__this_cpu_has_cap(arm64_features, cap) ||
+		__this_cpu_has_cap(arm64_errata, cap));
 void __init setup_cpu_features(void)
 	u32 cwg;

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