Re: [PATCH 2/2] KVM: VMX: Add knob to allow rejecting kvm_intel on inconsistent VMCS config

[Paolo Bonzini]

On 5/25/22 23:04, Sean Christopherson wrote:
> Add an off-by-default module param, reject_inconsistent_vmcs_config, to
> allow rejecting the load of kvm_intel if an inconsistent VMCS config is
> detected.  Continuing on with an inconsistent, degraded config is
> undesirable when the CPU is expected to support a given set of features,
> e.g. can result in a misconfigured VM if userspace doesn't cross-check
> KVM_GET_SUPPORTED_CPUID, and/or can result in poor performance due to
> lack of fast MSR switching.
>
> Signed-off-by: Sean Christopherson<seanjc@xxxxxxxxxx>
> ---
>   arch/x86/kvm/vmx/vmx.c | 20 +++++++++++++++++---
>   1 file changed, 17 insertions(+), 3 deletions(-)

Yeah let's do this by default.

Paolo