On 26/09/19 02:04, Jim Mattson wrote:
> When the guest CPUID information represents an AMD vCPU, return all
> zeroes for queries of undefined CPUID leaves, whether or not they are
> in range.
>
> Signed-off-by: Jim Mattson <jmattson@xxxxxxxxxx>
> Fixes: bd22f5cfcfe8f6 ("KVM: move and fix substitue search for missing CPUID entries")
> Reviewed-by: Marc Orr <marcorr@xxxxxxxxxx>
> Reviewed-by: Peter Shier <pshier@xxxxxxxxxx>
> Reviewed-by: Jacob Xu <jacobhxu@xxxxxxxxxx>
> Cc: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> ---
> arch/x86/kvm/cpuid.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
> index 35e2f930a4b79..0377d2820a7aa 100644
> --- a/arch/x86/kvm/cpuid.c
> +++ b/arch/x86/kvm/cpuid.c
> @@ -988,9 +988,11 @@ bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx,
> /*
> * Intel CPUID semantics treats any query for an out-of-range
> * leaf as if the highest basic leaf (i.e. CPUID.0H:EAX) were
> - * requested.
> + * requested. AMD CPUID semantics returns all zeroes for any
> + * undefined leaf, whether or not the leaf is in range.
> */
> - if (!entry && check_limit && !cpuid_function_in_range(vcpu, function)) {
> + if (!entry && check_limit && !guest_cpuid_is_amd(vcpu) &&
> + !cpuid_function_in_range(vcpu, function)) {
> max = kvm_find_cpuid_entry(vcpu, 0, 0);
> if (max) {
> function = max->eax;
>
Queued both, thanks.
Paolo
