Re: [PATCH v8 1/1] selftests/x86/xstate: Add xstate test cases for XSAVE feature

[Pengfei Xu]

On 2022-03-24 at 03:06:50 -0700, Chang S. Bae wrote:
> On 3/16/2022 5:40 AM, Pengfei Xu wrote:
> > 
> > +static inline void check_cpuid_xsave_availability(void)
> > +{
> > +	uint32_t eax, ebx, ecx, edx;
> > +
> > +	/*
> > +	 * CPUID.1:ECX.XSAVE[bit 26] enumerates general
> > +	 * support for the XSAVE feature set, including
> > +	 * XGETBV.
> > +	 */
> > +	__cpuid_count(1, 0, eax, ebx, ecx, edx);
> > +	if (!(ecx & CPUID_LEAF1_ECX_XSAVE_MASK))
> > +		fatal_error("cpuid: no CPU xsave support");
> > +	if (!(ecx & CPUID_LEAF1_ECX_OSXSAVE_MASK))
> > +		fatal_error("cpuid: no OS xsave support");
> 
> We need to skip the test when XSAVE is not available. See the point here:
> https://lore.kernel.org/lkml/8735j8aa9g.ffs@tglx/
> 
  Yes, it's better, will skip and exit if CPU doesn't support XSAVE or OS
  XSAVE.
  Thanks for suggestion!

  BR.
  -- Pengfei

> Thanks,
> Chang
> 
>