Re: [RFCv2 02/13] x86/kvm: Introduce KVM memory protection feature

Kirill A. Shutemov
2021-04-19T10:10:50Z

On Fri, Apr 16, 2021 at 06:10:30PM +0200, Borislav Petkov wrote:
> On Fri, Apr 16, 2021 at 06:40:55PM +0300, Kirill A. Shutemov wrote:
> > Provide basic helpers, KVM_FEATURE, CPUID flag and a hypercall.
> >
> > Host side doesn't provide the feature yet, so it is a dead code for now.
> >
> > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> > ---
> > arch/x86/include/asm/cpufeatures.h | 1 +
> > arch/x86/include/asm/kvm_para.h | 5 +++++
> > arch/x86/include/uapi/asm/kvm_para.h | 3 ++-
> > arch/x86/kernel/kvm.c | 17 +++++++++++++++++
> > include/uapi/linux/kvm_para.h | 3 ++-
> > 5 files changed, 27 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
> > index 84b887825f12..d8f3d2619913 100644
> > --- a/arch/x86/include/asm/cpufeatures.h
> > +++ b/arch/x86/include/asm/cpufeatures.h
> > @@ -238,6 +238,7 @@
> > #define X86_FEATURE_VMW_VMMCALL ( 8*32+19) /* "" VMware prefers VMMCALL hypercall instruction */
> > #define X86_FEATURE_SEV_ES ( 8*32+20) /* AMD Secure Encrypted Virtualization - Encrypted State */
> > #define X86_FEATURE_VM_PAGE_FLUSH ( 8*32+21) /* "" VM Page Flush MSR is supported */
> > +#define X86_FEATURE_KVM_MEM_PROTECTED ( 8*32+22) /* "" KVM memory protection extension */
>
> That feature bit is still unused.

Sorry. Will drop it.

--
Kirill A. Shutemov