Re: [PATCH v2 02/10] target/i386: disable PERFCORE when "-pmu" is configured

[Zhao Liu <zhao1.liu@intel.com>]

Hi Dongli,

> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> index b6d6167910..61a671028a 100644
> --- a/target/i386/cpu.c
> +++ b/target/i386/cpu.c
> @@ -7115,6 +7115,10 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
>              !(env->hflags & HF_LMA_MASK)) {
>              *edx &= ~CPUID_EXT2_SYSCALL;
>          }
> +
> +        if (kvm_enabled() && IS_AMD_CPU(env) && !cpu->enable_pmu) {

No need to check "kvm_enabled() && IS_AMD_CPU(env)" because:

 * "pmu" is a general CPU property option which should cover all PMU
   related features, and not kvm-specific/vendor-specific.
 * this bit is reserved on Intel. So the following operation doesn't
   affect Intel.

I think Xiaoyao's idea about checking in x86_cpu_expand_features() is
good. And I believe it's worth having another cleanup series to revisit
pmu dependencies. I can help you later to consolidate and move this
check to x86_cpu_expand_features(), so this patch can focus on correctly
defining the current dependency relationship.

With the above nit fixed,

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>