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* [PATCH] KVM: x86/pmu: Clear anythread deprecated bit when 0xa leaf is unsupported on the SVM
@ 2021-06-28  7:43 Like Xu
  2021-07-08 16:44 ` Paolo Bonzini
  0 siblings, 1 reply; 2+ messages in thread
From: Like Xu @ 2021-06-28  7:43 UTC (permalink / raw)
  To: Paolo Bonzini
  Cc: Sean Christopherson, Vitaly Kuznetsov, Wanpeng Li, Jim Mattson,
	Joerg Roedel, Stephane Eranian, Peter Zijlstra, Borislav Petkov,
	x86, kvm, linux-kernel

The AMD platform does not support the functions Ah CPUID leaf. The returned
results for this entry should all remain zero just like the native does:

AMD host:
   0x0000000a 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000 edx=0x00000000
(uncanny) AMD guest:
   0x0000000a 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000 edx=0x00008000

Fixes: cadbaa039b99 ("perf/x86/intel: Make anythread filter support conditional")
Signed-off-by: Like Xu <likexu@tencent.com>
---
 arch/x86/kvm/cpuid.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 0edda1fc4fe7..b1808e4fc7d5 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -765,7 +765,8 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
 
 		edx.split.num_counters_fixed = min(cap.num_counters_fixed, MAX_FIXED_COUNTERS);
 		edx.split.bit_width_fixed = cap.bit_width_fixed;
-		edx.split.anythread_deprecated = 1;
+		if (cap.version)
+			edx.split.anythread_deprecated = 1;
 		edx.split.reserved1 = 0;
 		edx.split.reserved2 = 0;
 
-- 
2.32.0


^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: [PATCH] KVM: x86/pmu: Clear anythread deprecated bit when 0xa leaf is unsupported on the SVM
  2021-06-28  7:43 [PATCH] KVM: x86/pmu: Clear anythread deprecated bit when 0xa leaf is unsupported on the SVM Like Xu
@ 2021-07-08 16:44 ` Paolo Bonzini
  0 siblings, 0 replies; 2+ messages in thread
From: Paolo Bonzini @ 2021-07-08 16:44 UTC (permalink / raw)
  To: Like Xu
  Cc: Sean Christopherson, Vitaly Kuznetsov, Wanpeng Li, Jim Mattson,
	Joerg Roedel, Stephane Eranian, Peter Zijlstra, Borislav Petkov,
	x86, kvm, linux-kernel

On 28/06/21 09:43, Like Xu wrote:
> The AMD platform does not support the functions Ah CPUID leaf. The returned
> results for this entry should all remain zero just like the native does:
> 
> AMD host:
>     0x0000000a 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000 edx=0x00000000
> (uncanny) AMD guest:
>     0x0000000a 0x00: eax=0x00000000 ebx=0x00000000 ecx=0x00000000 edx=0x00008000
> 
> Fixes: cadbaa039b99 ("perf/x86/intel: Make anythread filter support conditional")
> Signed-off-by: Like Xu <likexu@tencent.com>
> ---
>   arch/x86/kvm/cpuid.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
> index 0edda1fc4fe7..b1808e4fc7d5 100644
> --- a/arch/x86/kvm/cpuid.c
> +++ b/arch/x86/kvm/cpuid.c
> @@ -765,7 +765,8 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
>   
>   		edx.split.num_counters_fixed = min(cap.num_counters_fixed, MAX_FIXED_COUNTERS);
>   		edx.split.bit_width_fixed = cap.bit_width_fixed;
> -		edx.split.anythread_deprecated = 1;
> +		if (cap.version)
> +			edx.split.anythread_deprecated = 1;
>   		edx.split.reserved1 = 0;
>   		edx.split.reserved2 = 0;
>   
> 

Queued, thanks.

Paolo


^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2021-07-08 16:46 UTC | newest]

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2021-07-08 16:44 ` Paolo Bonzini

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