lkml.org 
[lkml]   [2016]   [Oct]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] x86/cpuid: expose AVX512_4VNNIW and AVX512_4FMAPS features to kvm guest
From
Date


On 28/10/2016 11:12, He Chen wrote:
> The spec can be found in Intel Software Developer Manual or in
> Instruction Set Extensions Programming Reference.
>
> Signed-off-by: Luwei Kang <luwei.kang@intel.com>
> Signed-off-by: He Chen <he.chen@linux.intel.com>
> ---
> arch/x86/kvm/cpuid.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
> index afa7bbb..328b169 100644
> --- a/arch/x86/kvm/cpuid.c
> +++ b/arch/x86/kvm/cpuid.c
> @@ -376,6 +376,10 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
> /* cpuid 7.0.ecx*/
> const u32 kvm_cpuid_7_0_ecx_x86_features = F(PKU) | 0 /*OSPKE*/;
>
> + /* cpuid 7.0.edx*/
> + const u32 kvm_cpuid_7_0_edx_x86_features =
> + 0x4 /* AVX512-4VNNIW */ | 0x8 /* AVX512-4FMAPS */;

Please define the new features in cpufeature.h first.

Thanks,

Paolo

> /* all calls to cpuid_count() should be made on the same cpu */
> get_cpu();
>
> @@ -458,12 +462,13 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
> /* PKU is not yet implemented for shadow paging. */
> if (!tdp_enabled)
> entry->ecx &= ~F(PKU);
> + entry->edx &= kvm_cpuid_7_0_edx_x86_features;
> } else {
> entry->ebx = 0;
> entry->ecx = 0;
> + entry->edx = 0;
> }
> entry->eax = 0;
> - entry->edx = 0;
> break;
> }
> case 9:
>

\
 
 \ /
  Last update: 2016-10-28 11:31    [W:0.052 / U:1.444 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site