Re: [PATCH RESEND v6 1/2] x86/cpu: Add support for UMONITOR/UMWAIT/TPAUSE

[Tao Xu <tao3.xu@intel.com>]

Hi Paolo,
Ping :)
On 10/11/2019 3:49 PM, Tao Xu wrote:
> On 10/11/2019 3:41 PM, Xu, Tao3 wrote:
> [...]
>> diff --git a/target/i386/kvm.c b/target/i386/kvm.c
>> index 11b9c854b5..a465c893b5 100644
>> --- a/target/i386/kvm.c
>> +++ b/target/i386/kvm.c
>> @@ -401,6 +401,12 @@ uint32_t kvm_arch_get_supported_cpuid(KVMState 
>> *s, uint32_t function,
>>           if (host_tsx_blacklisted()) {
>>               ret &= ~(CPUID_7_0_EBX_RTM | CPUID_7_0_EBX_HLE);
>>           }
>> +    } else if (function == 7 && index == 0 && reg == R_ECX) {
>> +        if (enable_cpu_pm) {
>> +            ret |= CPUID_7_0_ECX_WAITPKG;
>> +        } else {
>> +            ret &= ~CPUID_7_0_ECX_WAITPKG;
>> +        }
> 
> Hi Paolo,
> 
> I am sorry because I realize in KVM side, I keep cpuid mask WAITPKG as 0:
> 
> F(CLDEMOTE) | F(MOVDIRI) | F(MOVDIR64B) | 0 /*WAITPKG*/;
> 
> Therefore in QEMU side, we need to add CPUID_7_0_ECX_WAITPKG when 
> enable_cpu_pm is on. Otherwise, QEMU can't get this CPUID.
> 
> Could you review this part again? Thank you very much!
> 
> Tao