Re: [PATCH v2 11/11] KVM: SVM: Drop support for CPUs without NRIPS (NextRIP Save) support

[Maciej S. Szmigiero]

On 23.04.2022 04:14, Sean Christopherson wrote:
> Drop support for CPUs without NRIPS along with the associated module
> param.  Requiring NRIPS simplifies a handful of paths in KVM, especially
> paths where KVM has to do silly things when nrips=false but supported in
> hardware as there is no way to tell the CPU _not_ to use NRIPS.
>
> NRIPS was introduced in 2009, i.e. every AMD-based CPU released in the
> last decade should support NRIPS.
>
> Suggested-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> Not-signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>

To be honest, I think completely removing KVM support (rather than just nSVM)
for these older AMD CPUs is a bit too much.
I totally envision complaints coming after this change reaches distro kernels.

After all, even older Yonah parts remain supported on the VMX side.

Thanks,
Maciej