Re: [Qemu-devel] [PATCH 6/6] i386: Add Cascadelake-Server-4.1.1 CPU model

[Eduardo Habkost]

On Tue, Jun 25, 2019 at 01:35:17PM +0800, Tao Xu wrote:
> On 6/25/2019 1:00 PM, Eduardo Habkost wrote:
> > Add new version of Cascadelake-Server CPU model, setting
> > stepping=5 and enabling the IA32_ARCH_CAPABILITIES MSR.
> > 
> > The new feature will introduce a new host software requirement,
> > breaking our CPU model runnability promises.  This means we can't
> > enable the new CPU model version by default in QEMU 4.1, because
> > management software isn't ready yet to resolve CPU model aliases.
> > This is why the feature is being enabled in a
> > Cascadelake-Server-4.1.1 CPU model instead of
> > Cascadelake-Server-4.1.
> > 
> > Includes a test case to ensure the right combinations of
> > machine-type + CPU model + command-line feature flags will work
> > as expected.
> > 
> > Signed-off-by: Eduardo Habkost <address@hidden>
> > ---
> > Cc: "Hu, Robert" <address@hidden>
> > Cc: Tao Xu <address@hidden>
> > Cc: address@hidden,
> > Cc: "Lai, Paul C" <address@hidden>
> > ---
> >   target/i386/cpu.c                          | 15 +++++
> >   tests/acceptance/x86_cpu_model_versions.py | 71 ++++++++++++++++++++++
> >   2 files changed, 86 insertions(+)
> > 
> > diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> > index 121f568954..8edae04161 100644
> > --- a/target/i386/cpu.c
> > +++ b/target/i386/cpu.c
> > @@ -2607,6 +2607,21 @@ static X86CPUDefinition builtin_x86_defs[] = {
> ...
> > +        # versioned CPU model overrides machine-type:
> > +        vm = self.get_vm()
> > +        vm.add_args('-S')
> > +        vm.set_machine('pc-i440fx-4.0')
> > +        vm.add_args('-cpu', 
> > 'Cascadelake-Server-4.1,x-force-features=on,check=off,enforce=off')
> > +        vm.launch()
> > +        self.assertFalse(get_cpu_prop(vm, 'arch-capabilities'),
> > +                         'pc-i440fx-4.1 + Cascadelake-Server-4.1 should 
> > not have arch-capabilities')
> > +
> > +        vm = self.get_vm()
> > +        vm.add_args('-S')
> > +        vm.set_machine('pc-i440fx-4.0')
> > +        vm.add_args('-cpu', 
> > 'Cascadelake-Server-4.1.1,x-force-features=on,check=off,enforce=off')
> > +        vm.launch()
> > +        self.assertTrue(get_cpu_prop(vm, 'arch-capabilities'),
> > +                         'pc-i440fx-4.1 + Cascadelake-Server-4.1 should 
> > have arch-capabilities')
> Hi Eduardo
> 
> Could me ask why here the error show "Cascadelake-Server-4.1" instead of
> "Cascadelake-Server-4.1.1"?

My mistake.  Will fix it.

> 
> And will you add the MSR_ARCH_CAP_RDCL_NO, MSR_ARCH_CAP_IBRS_ALL, and
> MSR_ARCH_CAP_SKIP_L1DFL_VMENTRY into .features[FEAT_ARCH_CAPABILITIES]?

I will do it.  I don't know why I didn't notice them in the "Add
some MSR based features on Cascadelake-Server CPU model" patches
you sent.

-- 
Eduardo