Re: [Qemu-devel] [PATCH V2] i386: extended the cpuid_level when Intel PT is enabled

[Kang, Luwei]

> -----Original Message-----
> From: Paolo Bonzini [mailto:address@hidden
> Sent: Thursday, February 28, 2019 7:02 PM
> To: Kang, Luwei <address@hidden>; address@hidden; address@hidden; 
> address@hidden; address@hidden
> Cc: address@hidden
> Subject: Re: [PATCH V2] i386: extended the cpuid_level when Intel PT is 
> enabled
> 
> On 30/01/19 00:52, Luwei Kang wrote:
> > Intel Processor Trace required CPUID[0x14] but the cpuid_level have no
> > change when create a kvm guest with e.g. "-cpu qemu64,+intel-pt".
> >
> > Signed-off-by: Eduardo Habkost <address@hidden>
> > Signed-off-by: Luwei Kang <address@hidden>
> > ---
> >  hw/i386/pc.c      | 1 +
> >  target/i386/cpu.c | 9 +++++++++
> >  target/i386/cpu.h | 3 +++
> >  3 files changed, 13 insertions(+)
> >
> > diff --git a/hw/i386/pc.c b/hw/i386/pc.c index 73d688f..72a0a70 100644
> > --- a/hw/i386/pc.c
> > +++ b/hw/i386/pc.c
> > @@ -122,6 +122,7 @@ GlobalProperty pc_compat_3_1[] = {
> >      { "Cascadelake-Server" "-" TYPE_X86_CPU,  "mpx", "on" },
> >      { "Icelake-Client" "-" TYPE_X86_CPU,      "mpx", "on" },
> >      { "Icelake-Server" "-" TYPE_X86_CPU,      "mpx", "on" },
> > +    { TYPE_X86_CPU, "x-intel-pt-auto-level", "off" },
> >  };
> >  const size_t pc_compat_3_1_len = G_N_ELEMENTS(pc_compat_3_1);
> >
> > diff --git a/target/i386/cpu.c b/target/i386/cpu.c index
> > 2f54125..6dddd99 100644
> > --- a/target/i386/cpu.c
> > +++ b/target/i386/cpu.c
> > @@ -5023,6 +5023,13 @@ static void x86_cpu_expand_features(X86CPU *cpu, 
> > Error **errp)
> >          x86_cpu_adjust_feat_level(cpu, FEAT_C000_0001_EDX);
> >          x86_cpu_adjust_feat_level(cpu, FEAT_SVM);
> >          x86_cpu_adjust_feat_level(cpu, FEAT_XSAVE);
> > +
> > +        /* Intel Processor Trace requires CPUID[0x14] */
> > +        if ((env->features[FEAT_7_0_EBX] & CPUID_7_0_EBX_INTEL_PT) &&
> > +             kvm_enabled() && cpu->intel_pt_auto_level) {
> > +            x86_cpu_adjust_level(cpu, &cpu->env.cpuid_min_level, 0x14);
> > +        }
> > +
> >          /* SVM requires CPUID[0x8000000A] */
> >          if (env->features[FEAT_8000_0001_ECX] & CPUID_EXT3_SVM) {
> >              x86_cpu_adjust_level(cpu, &env->cpuid_min_xlevel,
> > 0x8000000A); @@ -5816,6 +5823,8 @@ static Property x86_cpu_properties[] = {
> >      DEFINE_PROP_INT32("x-hv-max-vps", X86CPU, hv_max_vps, -1),
> >      DEFINE_PROP_BOOL("x-hv-synic-kvm-only", X86CPU, hyperv_synic_kvm_only,
> >                       false),
> > +    DEFINE_PROP_BOOL("x-intel-pt-auto-level", X86CPU, intel_pt_auto_level,
> > +                     true),
> >      DEFINE_PROP_END_OF_LIST()
> >  };
> >
> > diff --git a/target/i386/cpu.h b/target/i386/cpu.h index
> > 59656a7..090baa4 100644
> > --- a/target/i386/cpu.h
> > +++ b/target/i386/cpu.h
> > @@ -1455,6 +1455,9 @@ struct X86CPU {
> >      /* Enable auto level-increase for all CPUID leaves */
> >      bool full_cpuid_auto_level;
> >
> > +    /* Enable auto level-increase for Intel Processor Trace leave */
> > +    bool intel_pt_auto_level;
> > +
> >      /* if true fill the top bits of the MTRR_PHYSMASKn variable range */
> >      bool fill_mtrr_mask;
> >
> >
> 
> Eduardo is back, but I've queued this anyway.
> 

Get it. Thanks!

Luwei Kang