[PATCH] arm64: Check for errata before evaluating cpu features

From: Dirk Mueller
Date: Wed Jul 25 2018 - 07:10:38 EST


From: Dirk Mueller <dmueller@xxxxxxxx>

Since commit d3aec8a28be3b8 ("arm64: capabilities: Restrict KPTI
detection to boot-time CPUs") we rely on errata flags being already
populated during feature enumeration. The order of errata and
features was flipped as part of commit ed478b3f9e4a ("arm64:
capabilities: Group handling of features and errata workarounds").

Return to the orginal order of errata and feature evaluation to
ensure errata flags are present during feature evaluation.

Fixes: ed478b3f9e4a ("arm64: capabilities: Group handling of
features and errata workarounds")
CC: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
CC: Marc Zyngier <marc.zyngier@xxxxxxx>
Signed-off-by: Dirk Mueller <dmueller@xxxxxxxx>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
---
arch/arm64/kernel/cpufeature.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index f24892a40d2c..c6d80743f4ed 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -1351,9 +1351,9 @@ static void __update_cpu_capabilities(const struct arm64_cpu_capabilities *caps,

static void update_cpu_capabilities(u16 scope_mask)
{
- __update_cpu_capabilities(arm64_features, scope_mask, "detected:");
__update_cpu_capabilities(arm64_errata, scope_mask,
"enabling workaround for");
+ __update_cpu_capabilities(arm64_features, scope_mask, "detected:");
}

static int __enable_cpu_capability(void *arg)
@@ -1408,8 +1408,8 @@ __enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps,

static void __init enable_cpu_capabilities(u16 scope_mask)
{
- __enable_cpu_capabilities(arm64_features, scope_mask);
__enable_cpu_capabilities(arm64_errata, scope_mask);
+ __enable_cpu_capabilities(arm64_features, scope_mask);
}

/*
--
2.18.0