[PATCH] arm64: Run enable method for errata work arounds on late CPUs
Dave Martin
Dave.Martin at arm.com
Wed Jan 17 04:25:49 PST 2018
On Wed, Jan 17, 2018 at 10:05:56AM +0000, Suzuki K Poulose wrote:
> When a CPU is brought up after we have finalised the system
> wide capabilities (i.e, features and errata), we make sure the
> new CPU doesn't need a new errata work around which has not been
> detected already. However we don't run enable() method on the new
> CPU for the errata work arounds already detected. This could
> cause the new CPU running without potential work arounds.
> It is upto the "enable()" method to decide if this CPU should
> do something about the errata.
>
> Fixes: commit 6a6efbb45b7d95c84 ("arm64: Verify CPU errata work arounds on hotplugged CPU")
> Cc: Will Deacon <will.deacon at arm.com>
> Cc: Mark Rutland <mark.rutland at arm.com>
> Cc: Andre Przywara <andre.przywara at arm.com>
> Cc: Catalin Marinas <catalin.marinas at arm.com>
> Cc: Dave Martin <dave.martin at arm.com>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose at arm.com>
> ---
> arch/arm64/kernel/cpu_errata.c | 9 ++++++---
> 1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
> index 90a9e465339c..54e41dfe41f6 100644
> --- a/arch/arm64/kernel/cpu_errata.c
> +++ b/arch/arm64/kernel/cpu_errata.c
> @@ -373,15 +373,18 @@ void verify_local_cpu_errata_workarounds(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)) {
> + for (; caps->matches; caps++) {
> + if (cpus_have_cap(caps->capability)) {
> + if (caps->enable)
> + caps->enable((void *)caps);
Do we really need this cast?
Can enable() fail, or do we already guarantee that it succeeds (by
having detected the cap in the first place)?
> + } else if (caps->matches(caps, SCOPE_LOCAL_CPU)) {
[...]
Cheers
---Dave
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