Re: [PATCH v15 04/14] KVM: x86: Add #CP support in guest exception dispatch

[Paolo Bonzini]

On 04/02/21 17:42, Sean Christopherson wrote:
> On Thu, Feb 04, 2021, Paolo Bonzini wrote:
> > On 03/02/21 22:46, Sean Christopherson wrote:
> > > diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
> > > index dbca1687ae8e..0b6dab6915a3 100644
> > > --- a/arch/x86/kvm/vmx/nested.c
> > > +++ b/arch/x86/kvm/vmx/nested.c
> > > @@ -2811,7 +2811,7 @@ static int nested_check_vm_entry_controls(struct kvm_vcpu *vcpu,
> > >                  /* VM-entry interruption-info field: deliver error code */
> > >                  should_have_error_code =
> > >                          intr_type == INTR_TYPE_HARD_EXCEPTION && prot_mode &&
> > > -                       x86_exception_has_error_code(vector);
> > > +                       x86_exception_has_error_code(vcpu, vector);
> > >                  if (CC(has_error_code != should_have_error_code))
> > >                          return -EINVAL;
> > >
> > > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> > > index 28fea7ff7a86..0288d6a364bd 100644
> > > --- a/arch/x86/kvm/x86.c
> > > +++ b/arch/x86/kvm/x86.c
> > > @@ -437,17 +437,20 @@ EXPORT_SYMBOL_GPL(kvm_spurious_fault);
> > >   #define EXCPT_CONTRIBUTORY     1
> > >   #define EXCPT_PF               2
> > >
> > > -static int exception_class(int vector)
> > > +static int exception_class(struct kvm_vcpu *vcpu, int vector)
> > >   {
> > >          switch (vector) {
> > >          case PF_VECTOR:
> > >                  return EXCPT_PF;
> > > +       case CP_VECTOR:
> > > +               if (vcpu->arch.cr4_guest_rsvd_bits & X86_CR4_CET)
> > > +                       return EXCPT_BENIGN;
> > > +               return EXCPT_CONTRIBUTORY;
> > >          case DE_VECTOR:
> > >          case TS_VECTOR:
> > >          case NP_VECTOR:
> > >          case SS_VECTOR:
> > >          case GP_VECTOR:
> > > -       case CP_VECTOR:
>
> This removal got lost when squasing.
>
> arch/x86/kvm/x86.c: In function ‘exception_class’:
> arch/x86/kvm/x86.c:455:2: error: duplicate case value
>    455 |  case CP_VECTOR:
>        |  ^~~~
> arch/x86/kvm/x86.c:446:2: note: previously used here
>    446 |  case CP_VECTOR:
>        |  ^~~~

Well, it shows that I haven't even started including those 
unlikely-for-5.12 patches (CET and #DB bus lock) in my builds, since 
today I was focusing on getting a kvm/next push done.

I'll probably push all those to kvm/intel-queue and remove them from 
everyone's view, for now.

Paolo