Re: [PULL 4/4] i386: Add "stibp" flag name

Lendacky, Thomas
2018-12-12T16:57:42Z

On 12/11/2018 02:53 PM, Eduardo Habkost wrote:
> The STIBP flag may be supported by the host KVM module, so QEMU
> can allow it to be configured manually, and it can be exposed to
> guests when using "-cpu host".
>
> No additional migration code is required because the whole
> contents of spec_ctrl is already migrated in the "cpu/spec_ctrl"
> section.
>
> Corresponding KVM patch was submitted at:
> https://lore.kernel.org/lkml/20181205191956.31480-1-ehabkost@redhat.com/
>
> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
> Message-Id: <20181210180250.31299-1-ehabkost@redhat.com>
> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
> ---
> target/i386/cpu.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> index 86a934d450..12f559b6af 100644
> --- a/target/i386/cpu.c
> +++ b/target/i386/cpu.c
> @@ -1042,7 +1042,7 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
> NULL, NULL, NULL, NULL,
> NULL, NULL, "pconfig", NULL,
> NULL, NULL, NULL, NULL,
> - NULL, NULL, "spec-ctrl", NULL,
> + NULL, NULL, "spec-ctrl", "stibp",

I guess I missed this earlier. Is there a corresponding patch for the AMD
STIBP bit (CPUID 0x80000008_EBX[15]) that is in KVM?

Thanks,
Tom

> NULL, "arch-capabilities", NULL, "ssbd",
> },
> .cpuid = {
>