[PATCH 4.14 33/71] arm64: Check for errata before evaluating cpu features

Greg Kroah-Hartman
2020-01-16T23:34:48Z

From: Dirk Mueller <dmueller@suse.com>

commit dc0e36581eb2da1aa3c63ceeff0f10ef1e899b2a upstream.

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@arm.com>
CC: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Dirk Mueller <dmueller@suse.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/arm64/kernel/cpufeature.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -1278,9 +1278,9 @@ static void __update_cpu_capabilities(co

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)
@@ -1335,8 +1335,8 @@ __enable_cpu_capabilities(const struct a

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);
}

/*