On Fri, Oct 12, 2018 at 11:04:28AM -0700, Jim Mattson wrote:
> x86_exception_has_error_code should deterministically return false if
> its operand is greater than or equal to 32.
>
> Fixes: 0447378a4a793 ("kvm: vmx: Nested VM-entry prereqs for event inj.")
> Cc: Marc Orr <marcorr@xxxxxxxxxx>
> Signed-off-by: Jim Mattson <jmattson@xxxxxxxxxx>
> ---
> arch/x86/kvm/x86.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
> index 67b9568613f3..b7890b248e64 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)
> BIT(NP_VECTOR) | BIT(SS_VECTOR) | BIT(GP_VECTOR) |
> BIT(PF_VECTOR) | BIT(AC_VECTOR);
>
> - return (1U << vector) & exception_has_error_code;
> + return vector < 32 && (1U << vector) & exception_has_error_code;
This feels like it should be a WARN_ON, i.e. KVM should be ensuring
the vector itself is valid prior to querying whether or not it should
have an error code.
> }
>
> static inline bool mmu_is_nested(struct kvm_vcpu *vcpu)
> --
> 2.19.1.331.ge82ca0e54c-goog
>
