On 7/30/2021 12:05 AM, Dave Hansen wrote:

On 7/29/21 8:02 AM, Tianyu Lan wrote:

quoted

quoted

There is x86_hyper_type to identify hypervisor type and we may check
this variable after checking X86_FEATURE_HYPERVISOR.

static inline bool hv_is_isolation_supported(void)
{
     if (!cpu_feature_enabled(X86_FEATURE_HYPERVISOR))
         return 0;

         if (x86_hyper_type != X86_HYPER_MS_HYPERV)
                 return 0;

     // out of line function call:
     return __hv_is_isolation_supported();
}

Looks fine.  You just might want to use this existing helper:

static inline bool hypervisor_is_type(enum x86_hypervisor_type type)
{
         return x86_hyper_type == type;
}

Yes,thanks for suggestion and will update in the next version.