Re: [V8 2/4] x86/xsaves: enable xsaves/xrstors/xsavec in xen

["Jan Beulich" <JBeulich@suse.com>]

>>> On 29.10.15 at 10:47, <shuai.ruan@linux.intel.com> wrote:
> On Thu, Oct 29, 2015 at 02:59:38AM -0600, Jan Beulich wrote:
>> >>> On 29.10.15 at 08:58, <shuai.ruan@linux.intel.com> wrote:
>> > Yes. I will use the exist function "hvm_save_cpu_msrs" to save this msr. I 
>> > intend to add save msr logic before "ASSERT(ctxt->count <= msr_count_max);" in 
> 
>> > hvm_save_cpu_msrs. Is that Ok ?
>> 
>> No, the code belongs in vmx_save_msr() (and its sibling functions).
>> 
> Ok.
> For there is no new area added in vmcs for xss_msr, I will use
> "
>     if ( cpu_has_xsaves)
>     {
>         ctxt->msr[ctxt->count].val = v->arch.hvm_vcpu.msr_xss;
>         if ( ctxt->msr[ctxt->count].val )
>              ctxt->msr[ctxt->count++].index = MSR_IA32_XSS;
>     }
> " to save xss_msr. Is it ok to add the save logic between 
> "vmx_vmcs_enter(v);" and "vmx_vmcs_exit(v);" ? Or just add the save logic 
> after "vmx_vmcs_exit(v);" ?

I think it'd be fine either way, but obviously the VMX maintainers
will have the final say.

Jan