Re: [PATCH v2] KVM: SVM: Don't skip unrelated instruction if INT3/INTO is replaced

[Sean Christopherson <seanjc@google.com>]

On Wed, Oct 29, 2025, Omar Sandoval wrote:
> @@ -2153,6 +2158,10 @@ u64 vcpu_tsc_khz(struct kvm_vcpu *vcpu);
>  #define EMULTYPE_PF		    (1 << 6)
>  #define EMULTYPE_COMPLETE_USER_EXIT (1 << 7)
>  #define EMULTYPE_WRITE_PF_TO_SP	    (1 << 8)
> +#define EMULTYPE_SKIP_SOFT_INT	    (1 << 9)
> +
> +#define EMULTYPE_SET_SOFT_INT_VECTOR(v)	(((v) & 0xff) << 16)
> +#define EMULTYPE_GET_SOFT_INT_VECTOR(e)	(((e) >> 16) & 0xff)
>  
>  static inline bool kvm_can_emulate_event_vectoring(int emul_type)
>  {

...

> +static int svm_update_soft_interrupt_rip(struct kvm_vcpu *vcpu, u8 vector)
>  {
> +	const int emul_type = EMULTYPE_SKIP | EMULTYPE_SKIP_SOFT_INT |
> +			      EMULTYPE_GET_SOFT_INT_VECTOR(vector);

Apparently our friendly neighborhood test bots[*] are the only ones that tested
this :-)

This should be EMULTYPE_SET_SOFT_INT_VECTOR()
                        ^
                        |

And I suspect EMULTYPE_SET_SOFT_INT_VECTOR() needs to cast (v) to a u32 so as
not to overflow the shift.


[*] https://lore.kernel.org/all/202510310909.y5ClH2qW-lkp@intel.com