Re: [PATCH 2/2] KVM: x86: always expose VIRT_SSBD to guests

2019-08-19 Thread Paolo Bonzini
On 15/08/19 19:14, Eduardo Habkost wrote: > On Thu, Aug 15, 2019 at 09:41:23AM +0200, Paolo Bonzini wrote: >> Even though it is preferrable to use SPEC_CTRL (represented by >> X86_FEATURE_AMD_SSBD) instead of VIRT_SPEC, VIRT_SPEC is always >> supported anyway because otherwise it would be

Re: [PATCH 2/2] KVM: x86: always expose VIRT_SSBD to guests

2019-08-15 Thread Eduardo Habkost
On Thu, Aug 15, 2019 at 09:41:23AM +0200, Paolo Bonzini wrote: > Even though it is preferrable to use SPEC_CTRL (represented by > X86_FEATURE_AMD_SSBD) instead of VIRT_SPEC, VIRT_SPEC is always > supported anyway because otherwise it would be impossible to > migrate from old to new CPUs. Make

[PATCH 2/2] KVM: x86: always expose VIRT_SSBD to guests

2019-08-15 Thread Paolo Bonzini
Even though it is preferrable to use SPEC_CTRL (represented by X86_FEATURE_AMD_SSBD) instead of VIRT_SPEC, VIRT_SPEC is always supported anyway because otherwise it would be impossible to migrate from old to new CPUs. Make this apparent in the result of KVM_GET_SUPPORTED_CPUID as well. Cc: