On 01/03/20 11:47, Jan Kiszka wrote:
> From: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
>
> After 43561123ab37, found is not set correctly in case of leaves 0BH,
> 1FH, or anything out-of-range. This is currently harmless for the return
> value because the only caller evaluating it passes leaf 0x80000008.
>
> However, the trace entry is now misleading due to this inaccuracy. It is
> furthermore misleading because it reports the effective function, not
> the originally passed one. Fix that as well.
>
> Fixes: 43561123ab37 ("kvm: x86: Improve emulation of CPUID leaves 0BH and 1FH")
> Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
Queued, thanks.
Paolo
> ---
> arch/x86/kvm/cpuid.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
> index b1c469446b07..79a738f313f8 100644
> --- a/arch/x86/kvm/cpuid.c
> +++ b/arch/x86/kvm/cpuid.c
> @@ -1000,13 +1000,12 @@ static bool cpuid_function_in_range(struct kvm_vcpu *vcpu, u32 function)
> bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx,
> u32 *ecx, u32 *edx, bool check_limit)
> {
> - u32 function = *eax, index = *ecx;
> + u32 orig_function = *eax, function = *eax, index = *ecx;
> struct kvm_cpuid_entry2 *entry;
> struct kvm_cpuid_entry2 *max;
> bool found;
>
> entry = kvm_find_cpuid_entry(vcpu, function, index);
> - found = entry;
> /*
> * Intel CPUID semantics treats any query for an out-of-range
> * leaf as if the highest basic leaf (i.e. CPUID.0H:EAX) were
> @@ -1049,7 +1048,8 @@ bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx,
> }
> }
> }
> - trace_kvm_cpuid(function, *eax, *ebx, *ecx, *edx, found);
> + found = entry;
> + trace_kvm_cpuid(orig_function, *eax, *ebx, *ecx, *edx, found);
> return found;
> }
> EXPORT_SYMBOL_GPL(kvm_cpuid);
> --
> 2.16.4
>
