diff mbox series

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

Message ID 20210203113421.5759-5-weijiang.yang@intel.com (mailing list archive)
State New, archived
Headers show
Series Introduce support for guest CET feature | expand

Commit Message

Yang Weijiang Feb. 3, 2021, 11:34 a.m. UTC
Add handling for Control Protection (#CP) exceptions, vector 21, used
and introduced by Intel's Control-Flow Enforcement Technology (CET).
relevant CET violation case.  See Intel's SDM for details.

Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
---
 arch/x86/include/uapi/asm/kvm.h | 1 +
 arch/x86/kvm/x86.c              | 1 +
 arch/x86/kvm/x86.h              | 2 +-
 3 files changed, 3 insertions(+), 1 deletion(-)

Comments

Sean Christopherson Feb. 3, 2021, 9:46 p.m. UTC | #1
On Wed, Feb 03, 2021, Yang Weijiang wrote:
> Add handling for Control Protection (#CP) exceptions, vector 21, used
> and introduced by Intel's Control-Flow Enforcement Technology (CET).
> relevant CET violation case.  See Intel's SDM for details.
> 
> Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
> ---
>  arch/x86/include/uapi/asm/kvm.h | 1 +
>  arch/x86/kvm/x86.c              | 1 +
>  arch/x86/kvm/x86.h              | 2 +-
>  3 files changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
> index 8e76d3701db3..507263d1d0b2 100644
> --- a/arch/x86/include/uapi/asm/kvm.h
> +++ b/arch/x86/include/uapi/asm/kvm.h
> @@ -32,6 +32,7 @@
>  #define MC_VECTOR 18
>  #define XM_VECTOR 19
>  #define VE_VECTOR 20
> +#define CP_VECTOR 21
>  
>  /* Select x86 specific features in <linux/kvm.h> */
>  #define __KVM_HAVE_PIT
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 99f787152d12..d9d3bae40a8c 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -436,6 +436,7 @@ static int exception_class(int vector)
>  	case NP_VECTOR:
>  	case SS_VECTOR:
>  	case GP_VECTOR:
> +	case CP_VECTOR:
>  		return EXCPT_CONTRIBUTORY;
>  	default:
>  		break;
> diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
> index c5ee0f5ce0f1..bdbd0b023ecc 100644
> --- a/arch/x86/kvm/x86.h
> +++ b/arch/x86/kvm/x86.h
> @@ -116,7 +116,7 @@ static inline bool x86_exception_has_error_code(unsigned int vector)
>  {
>  	static u32 exception_has_error_code = BIT(DF_VECTOR) | BIT(TS_VECTOR) |
>  			BIT(NP_VECTOR) | BIT(SS_VECTOR) | BIT(GP_VECTOR) |
> -			BIT(PF_VECTOR) | BIT(AC_VECTOR);
> +			BIT(PF_VECTOR) | BIT(AC_VECTOR) | BIT(CP_VECTOR);

These need to be conditional on CET being exposed to the guest.  TBD exceptions
are non-contributory and don't have an error code.  Found when running unit
tests in L1 with a kvm/queue as L1, but an older L0.  cr4_guest_rsvd_bits can be
used to avoid guest_cpuid_has() lookups.

The SDM also gets this wrong.  Section 26.2.1.3, VM-Entry Control Fields, needs
to be updated to add #CP to the list.

  — The field's deliver-error-code bit (bit 11) is 1 if each of the following
    holds: (1) the interruption type is hardware exception; (2) bit 0
    (corresponding to CR0.PE) is set in the CR0 field in the guest-state area;
    (3) IA32_VMX_BASIC[56] is read as 0 (see Appendix A.1); and (4) the vector
    indicates one of the following exceptions: #DF (vector 8), #TS (10),
    #NP (11), #SS (12), #GP (13), #PF (14), or #AC (17).

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:
                return EXCPT_CONTRIBUTORY;
        default:
                break;
@@ -588,8 +591,8 @@ static void kvm_multiple_exception(struct kvm_vcpu *vcpu,
                kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
                return;
        }
-       class1 = exception_class(prev_nr);
-       class2 = exception_class(nr);
+       class1 = exception_class(vcpu, prev_nr);
+       class2 = exception_class(vcpu, nr);
        if ((class1 == EXCPT_CONTRIBUTORY && class2 == EXCPT_CONTRIBUTORY)
                || (class1 == EXCPT_PF && class2 != EXCPT_BENIGN)) {
                /*
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index a14da36a30ed..dce756ffb577 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -120,12 +120,16 @@ static inline bool is_la57_mode(struct kvm_vcpu *vcpu)
 #endif
 }

-static inline bool x86_exception_has_error_code(unsigned int vector)
+static inline bool x86_exception_has_error_code(struct kvm_vcpu *vcpu,
+                                               unsigned int vector)
 {
        static u32 exception_has_error_code = BIT(DF_VECTOR) | BIT(TS_VECTOR) |
                        BIT(NP_VECTOR) | BIT(SS_VECTOR) | BIT(GP_VECTOR) |
                        BIT(PF_VECTOR) | BIT(AC_VECTOR) | BIT(CP_VECTOR);

+       if (vector == CP_VECTOR && (vcpu->arch.cr4_guest_rsvd_bits & X86_CR4_CET))
+               return false;
+
        return (1U << vector) & exception_has_error_code;
 }
Yang Weijiang Feb. 4, 2021, 7:22 a.m. UTC | #2
On Wed, Feb 03, 2021 at 01:46:42PM -0800, Sean Christopherson wrote:
> On Wed, Feb 03, 2021, Yang Weijiang wrote:
> > Add handling for Control Protection (#CP) exceptions, vector 21, used
> > and introduced by Intel's Control-Flow Enforcement Technology (CET).
> > relevant CET violation case.  See Intel's SDM for details.
> > 
> > Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
> > ---
> >  arch/x86/include/uapi/asm/kvm.h | 1 +
> >  arch/x86/kvm/x86.c              | 1 +
> >  arch/x86/kvm/x86.h              | 2 +-
> >  3 files changed, 3 insertions(+), 1 deletion(-)
> > 
> > diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
> > index 8e76d3701db3..507263d1d0b2 100644
> > --- a/arch/x86/include/uapi/asm/kvm.h
> > +++ b/arch/x86/include/uapi/asm/kvm.h
> > @@ -32,6 +32,7 @@
> >  #define MC_VECTOR 18
> >  #define XM_VECTOR 19
> >  #define VE_VECTOR 20
> > +#define CP_VECTOR 21
> >  
> >  /* Select x86 specific features in <linux/kvm.h> */
> >  #define __KVM_HAVE_PIT
> > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> > index 99f787152d12..d9d3bae40a8c 100644
> > --- a/arch/x86/kvm/x86.c
> > +++ b/arch/x86/kvm/x86.c
> > @@ -436,6 +436,7 @@ static int exception_class(int vector)
> >  	case NP_VECTOR:
> >  	case SS_VECTOR:
> >  	case GP_VECTOR:
> > +	case CP_VECTOR:
> >  		return EXCPT_CONTRIBUTORY;
> >  	default:
> >  		break;
> > diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
> > index c5ee0f5ce0f1..bdbd0b023ecc 100644
> > --- a/arch/x86/kvm/x86.h
> > +++ b/arch/x86/kvm/x86.h
> > @@ -116,7 +116,7 @@ static inline bool x86_exception_has_error_code(unsigned int vector)
> >  {
> >  	static u32 exception_has_error_code = BIT(DF_VECTOR) | BIT(TS_VECTOR) |
> >  			BIT(NP_VECTOR) | BIT(SS_VECTOR) | BIT(GP_VECTOR) |
> > -			BIT(PF_VECTOR) | BIT(AC_VECTOR);
> > +			BIT(PF_VECTOR) | BIT(AC_VECTOR) | BIT(CP_VECTOR);
> 
> These need to be conditional on CET being exposed to the guest.  TBD exceptions
> are non-contributory and don't have an error code.  Found when running unit
> tests in L1 with a kvm/queue as L1, but an older L0.  cr4_guest_rsvd_bits can be
> used to avoid guest_cpuid_has() lookups.
> 
> The SDM also gets this wrong.  Section 26.2.1.3, VM-Entry Control Fields, needs
> to be updated to add #CP to the list.
> 
>   — The field's deliver-error-code bit (bit 11) is 1 if each of the following
>     holds: (1) the interruption type is hardware exception; (2) bit 0
>     (corresponding to CR0.PE) is set in the CR0 field in the guest-state area;
>     (3) IA32_VMX_BASIC[56] is read as 0 (see Appendix A.1); and (4) the vector
>     indicates one of the following exceptions: #DF (vector 8), #TS (10),
>     #NP (11), #SS (12), #GP (13), #PF (14), or #AC (17).
> 
> 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:
>                 return EXCPT_CONTRIBUTORY;
>         default:
>                 break;
> @@ -588,8 +591,8 @@ static void kvm_multiple_exception(struct kvm_vcpu *vcpu,
>                 kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
>                 return;
>         }
> -       class1 = exception_class(prev_nr);
> -       class2 = exception_class(nr);
> +       class1 = exception_class(vcpu, prev_nr);
> +       class2 = exception_class(vcpu, nr);
>         if ((class1 == EXCPT_CONTRIBUTORY && class2 == EXCPT_CONTRIBUTORY)
>                 || (class1 == EXCPT_PF && class2 != EXCPT_BENIGN)) {
>                 /*
> diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
> index a14da36a30ed..dce756ffb577 100644
> --- a/arch/x86/kvm/x86.h
> +++ b/arch/x86/kvm/x86.h
> @@ -120,12 +120,16 @@ static inline bool is_la57_mode(struct kvm_vcpu *vcpu)
>  #endif
>  }
> 
> -static inline bool x86_exception_has_error_code(unsigned int vector)
> +static inline bool x86_exception_has_error_code(struct kvm_vcpu *vcpu,
> +                                               unsigned int vector)
>  {
>         static u32 exception_has_error_code = BIT(DF_VECTOR) | BIT(TS_VECTOR) |
>                         BIT(NP_VECTOR) | BIT(SS_VECTOR) | BIT(GP_VECTOR) |
>                         BIT(PF_VECTOR) | BIT(AC_VECTOR) | BIT(CP_VECTOR);
> 
> +       if (vector == CP_VECTOR && (vcpu->arch.cr4_guest_rsvd_bits & X86_CR4_CET))
> +               return false;
> +
>         return (1U << vector) & exception_has_error_code;
>  }
Thanks Sean for catching this!

Hi, Paolo,
Do I need to send another version to include Sean's change?

> 
> 
>
Paolo Bonzini Feb. 4, 2021, 8:24 a.m. UTC | #3
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:
>                 return EXCPT_CONTRIBUTORY;
>         default:
>                 break;
> @@ -588,8 +591,8 @@ static void kvm_multiple_exception(struct kvm_vcpu *vcpu,
>                 kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
>                 return;
>         }
> -       class1 = exception_class(prev_nr);
> -       class2 = exception_class(nr);
> +       class1 = exception_class(vcpu, prev_nr);
> +       class2 = exception_class(vcpu, nr);
>         if ((class1 == EXCPT_CONTRIBUTORY && class2 == EXCPT_CONTRIBUTORY)
>                 || (class1 == EXCPT_PF && class2 != EXCPT_BENIGN)) {
>                 /*
> diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
> index a14da36a30ed..dce756ffb577 100644
> --- a/arch/x86/kvm/x86.h
> +++ b/arch/x86/kvm/x86.h
> @@ -120,12 +120,16 @@ static inline bool is_la57_mode(struct kvm_vcpu *vcpu)
>  #endif
>  }
> 
> -static inline bool x86_exception_has_error_code(unsigned int vector)
> +static inline bool x86_exception_has_error_code(struct kvm_vcpu *vcpu,
> +                                               unsigned int vector)
>  {
>         static u32 exception_has_error_code = BIT(DF_VECTOR) | BIT(TS_VECTOR) |
>                         BIT(NP_VECTOR) | BIT(SS_VECTOR) | BIT(GP_VECTOR) |
>                         BIT(PF_VECTOR) | BIT(AC_VECTOR) | BIT(CP_VECTOR);
> 
> +       if (vector == CP_VECTOR && (vcpu->arch.cr4_guest_rsvd_bits & X86_CR4_CET))
> +               return false;
> +
>         return (1U << vector) & exception_has_error_code;
>  }
> 
> 
> 
> 

Squashed, thanks.  I made a small change to the last hunk:

         if (!((1U << vector) & exception_has_error_code))
                 return false;

         if (vector == CP_VECTOR)
                 return !(vcpu->arch.cr4_guest_rsvd_bits & X86_CR4_CET);

         return true;
Paolo Bonzini Feb. 4, 2021, 8:28 a.m. UTC | #4
On 04/02/21 08:22, Yang Weijiang wrote:
> Thanks Sean for catching this!
> 
> Hi, Paolo,
> Do I need to send another version to include Sean's change?

No, it's okay.

Paolo
Sean Christopherson Feb. 4, 2021, 4:42 p.m. UTC | #5
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:
      |  ^~~~

> >                 return EXCPT_CONTRIBUTORY;
> >         default:
> >                 break;
> > @@ -588,8 +591,8 @@ static void kvm_multiple_exception(struct kvm_vcpu *vcpu,
> >                 kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
> >                 return;
> >         }
> > -       class1 = exception_class(prev_nr);
> > -       class2 = exception_class(nr);
> > +       class1 = exception_class(vcpu, prev_nr);
> > +       class2 = exception_class(vcpu, nr);
> >         if ((class1 == EXCPT_CONTRIBUTORY && class2 == EXCPT_CONTRIBUTORY)
> >                 || (class1 == EXCPT_PF && class2 != EXCPT_BENIGN)) {
> >                 /*
> > diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
> > index a14da36a30ed..dce756ffb577 100644
> > --- a/arch/x86/kvm/x86.h
> > +++ b/arch/x86/kvm/x86.h
> > @@ -120,12 +120,16 @@ static inline bool is_la57_mode(struct kvm_vcpu *vcpu)
> >  #endif
> >  }
> > 
> > -static inline bool x86_exception_has_error_code(unsigned int vector)
> > +static inline bool x86_exception_has_error_code(struct kvm_vcpu *vcpu,
> > +                                               unsigned int vector)
> >  {
> >         static u32 exception_has_error_code = BIT(DF_VECTOR) | BIT(TS_VECTOR) |
> >                         BIT(NP_VECTOR) | BIT(SS_VECTOR) | BIT(GP_VECTOR) |
> >                         BIT(PF_VECTOR) | BIT(AC_VECTOR) | BIT(CP_VECTOR);
> > 
> > +       if (vector == CP_VECTOR && (vcpu->arch.cr4_guest_rsvd_bits & X86_CR4_CET))
> > +               return false;
> > +
> >         return (1U << vector) & exception_has_error_code;
> >  }
> > 
> > 
> > 
> > 
> 
> Squashed, thanks.  I made a small change to the last hunk:
> 
>         if (!((1U << vector) & exception_has_error_code))
>                 return false;
> 
>         if (vector == CP_VECTOR)
>                 return !(vcpu->arch.cr4_guest_rsvd_bits & X86_CR4_CET);
> 
>         return true;

Ha, I guessed wrong, that was my first pass at it :-)
Paolo Bonzini Feb. 4, 2021, 5:29 p.m. UTC | #6
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
diff mbox series

Patch

diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index 8e76d3701db3..507263d1d0b2 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -32,6 +32,7 @@ 
 #define MC_VECTOR 18
 #define XM_VECTOR 19
 #define VE_VECTOR 20
+#define CP_VECTOR 21
 
 /* Select x86 specific features in <linux/kvm.h> */
 #define __KVM_HAVE_PIT
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 99f787152d12..d9d3bae40a8c 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -436,6 +436,7 @@  static int exception_class(int vector)
 	case NP_VECTOR:
 	case SS_VECTOR:
 	case GP_VECTOR:
+	case CP_VECTOR:
 		return EXCPT_CONTRIBUTORY;
 	default:
 		break;
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index c5ee0f5ce0f1..bdbd0b023ecc 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -116,7 +116,7 @@  static inline bool x86_exception_has_error_code(unsigned int vector)
 {
 	static u32 exception_has_error_code = BIT(DF_VECTOR) | BIT(TS_VECTOR) |
 			BIT(NP_VECTOR) | BIT(SS_VECTOR) | BIT(GP_VECTOR) |
-			BIT(PF_VECTOR) | BIT(AC_VECTOR);
+			BIT(PF_VECTOR) | BIT(AC_VECTOR) | BIT(CP_VECTOR);
 
 	return (1U << vector) & exception_has_error_code;
 }