On Mon, Aug 27, 2018 at 04:33:09PM +0200, Mian Yousaf Kaukab wrote:
> Return status based no ssbd_state. Return string "Unknown" in case
> CONFIG_ARM64_SSBD is disabled or arch workaround2 is not available
> in the firmware.
>
> Signed-off-by: Mian Yousaf Kaukab <ykau...@suse.de>
> ---
> arch/arm64/kernel/cpu_errata.c | 20 ++++++++++++++++++++
> 1 file changed, 20 insertions(+)
>
> diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
> index 8469d3be7b15..8b60aa30a3fa 100644
> --- a/arch/arm64/kernel/cpu_errata.c
> +++ b/arch/arm64/kernel/cpu_errata.c
> @@ -744,4 +744,24 @@ ssize_t cpu_show_spectre_v2(struct device *dev, struct
> device_attribute *attr,
> return sprintf(buf, "Not affected\n");
> }
>
> +ssize_t cpu_show_spec_store_bypass(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + switch (arm64_get_ssbd_state()) {
> + case ARM64_SSBD_MITIGATED:
> + return sprintf(buf, "Not affected\n");
> +
> + case ARM64_SSBD_KERNEL:
> + case ARM64_SSBD_FORCE_ENABLE:
> + return sprintf(buf,
> + "Mitigation: Speculative Store Bypass disabled");
> +
> + case ARM64_SSBD_FORCE_DISABLE:
> + return sprintf(buf, "Vulnerable\n");
> +
> + default: /* ARM64_SSBD_UNKNOWN*/
> + return sprintf(buf, "Unknown\n");
> + }
> +}
This probably wants extending for CPUs that support SSBS (see
for-next/core).
Will
