> -----Original Message----- > From: Eduardo Habkost [mailto:ehabkost@xxxxxxxxxx] > Sent: Monday, June 11, 2018 3:51 PM > To: Moger, Babu <Babu.Moger@xxxxxxx> > Cc: mst@xxxxxxxxxx; marcel.apfelbaum@xxxxxxxxx; pbonzini@xxxxxxxxxx; > rth@xxxxxxxxxxx; mtosatti@xxxxxxxxxx; qemu-devel@xxxxxxxxxx; > kvm@xxxxxxxxxxxxxxx; kash@xxxxxxxxxxxxxx; geoff@xxxxxxxxxxxxxxx > Subject: Re: [PATCH v13 3/5] i386: Enable TOPOEXT feature on AMD EPYC > CPU > > On Fri, Jun 08, 2018 at 06:56:19PM -0400, Babu Moger wrote: > > Enable TOPOEXT feature on EPYC CPU. This is required to support > > hyperthreading on VM guests. Also extend xlevel to 0x8000001E. > > > > TOPOEXT feature is disabled for legacy machines. > > > > Signed-off-by: Babu Moger <babu.moger@xxxxxxx> > > --- > > target/i386/cpu.c | 7 +++++++ > > 1 file changed, 7 insertions(+) > > > > diff --git a/target/i386/cpu.c b/target/i386/cpu.c > > index d3411ed..4dd9a82 100644 > > --- a/target/i386/cpu.c > > +++ b/target/i386/cpu.c > > @@ -2574,6 +2574,7 @@ static X86CPUDefinition builtin_x86_defs[] = { > > .xlevel = 0x8000000A, > > .model_id = "AMD EPYC Processor", > > .cache_info = &epyc_cache_info, > > + .auto_topoext = 1, > > }, > > { > > .name = "EPYC-IBPB", > > @@ -2621,6 +2622,7 @@ static X86CPUDefinition builtin_x86_defs[] = { > > .xlevel = 0x8000000A, > > .model_id = "AMD EPYC Processor (with IBPB)", > > .cache_info = &epyc_cache_info, > > + .auto_topoext = 1, > > }, > > }; > > > > @@ -4672,6 +4674,11 @@ static void x86_cpu_expand_features(X86CPU > *cpu, Error **errp) > > x86_cpu_adjust_level(cpu, &env->cpuid_min_xlevel, 0x8000000A); > > } > > > > + /* TOPOEXT feature requires 0x8000001E */ > > + if (env->features[FEAT_8000_0001_ECX] & CPUID_EXT3_TOPOEXT) { > > + x86_cpu_adjust_level(cpu, &env->cpuid_min_xlevel, 0x8000001E); > > + } > > I suggest moving this hunk to a separate patch. I'm not 100% Sure. Will move it to separate patch. > sure yet if this will require compat_props code to disable > auto-xlevel-increase on older machine-types. > > -- > Eduardo
