Re: [RFC PATCH v4 0/8] This patch-set is to enable Guest CET support

[Sean Christopherson]

On Mon, Mar 18, 2019 at 11:03:43PM +0800, Yang Weijiang wrote:
> Control-flow Enforcement Technology (CET) provides protection against
> return/jump-oriented programming (ROP) attacks. To make kvm Guest OS own
> the capability, this patch-set is required. It enables CET related CPUID
> report, xsaves/xrstors, vmx entry configuration etc. for Guest OS.

...

> Yang Weijiang (7):
>   KVM:VMX: Define CET VMCS fields and bits
>   KVM:CPUID: Add CET CPUID support for Guest
>   KVM:CPUID: Fix xsaves area size calculation for CPUID.(EAX=0xD,ECX=1).

I like the earnestness of scoping to CPUID, but "KVM: x86:" is sufficient
and more correct, e.g. ARM has CPUID as well and most architectures have
an equivalent.

>   KVM:VMX: Pass through host CET related MSRs to Guest.
>   KVM:VMX: Load Guest CET via VMCS when CET is enabled in Guest
>   KVM:x86: Allow Guest to set supported bits in XSS
>   KVM:x86: Add user-space read/write interface for CET MSRs

Please add spaces between KVM: and the more specific scope.

> 
>  arch/x86/include/asm/kvm_host.h  |  5 +-
>  arch/x86/include/asm/msr-index.h |  2 +
>  arch/x86/include/asm/vmx.h       |  8 +++
>  arch/x86/kvm/cpuid.c             | 53 ++++++++++++++------
>  arch/x86/kvm/vmx.c               | 86 ++++++++++++++++++++++++++++++--

Please rebase to the latest KVM for the next version, this is getting
fairly stale.  Thanks!

>  arch/x86/kvm/x86.c               | 32 +++++++++++-
>  arch/x86/kvm/x86.h               |  4 ++
>  7 files changed, 167 insertions(+), 23 deletions(-)
> 
> -- 
> 2.17.1
>