Re: [PATCH] EDAC/mce_amd: Do not load edac_mce_amd module on guests

From: Yazen Ghannam
Date: Thu Jul 08 2021 - 16:41:12 EST


On Mon, Jun 28, 2021 at 12:27:40PM -0500, Smita Koralahalli wrote:
> Hypervisors may not expose SMCA feature to the guest.
>
> Check for X86_FEATURE_HYPERVISOR on entry in mce_amd_init() and return
> -ENODEV if set.
>
> Suggested-by: Borislav Petkov <bp@xxxxxxx>
> Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@xxxxxxx>
> ---
> drivers/edac/mce_amd.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/edac/mce_amd.c b/drivers/edac/mce_amd.c
> index 5dd905a3f30c..1a1629166aa3 100644
> --- a/drivers/edac/mce_amd.c
> +++ b/drivers/edac/mce_amd.c
> @@ -1176,6 +1176,9 @@ static int __init mce_amd_init(void)
> c->x86_vendor != X86_VENDOR_HYGON)
> return -ENODEV;
>
> + if (cpu_feature_enabled(X86_FEATURE_HYPERVISOR))
> + return -ENODEV;
> +
> if (boot_cpu_has(X86_FEATURE_SMCA)) {
> xec_mask = 0x3f;
> goto out;
> --

Looks good to me.

Reviewed-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>

Thanks,
Yazen