Re: [PATCH 3/4] KVM: nVMX: Check all exceptions for intercept during delivery to L2

[Paolo Bonzini <pbonzini@redhat.com>]

Il 25/09/2013 11:51, Gleb Natapov ha scritto:
> All exceptions should be checked for intercept during delivery to L2,
> but we check only #PF currently. Drop nested_run_pending while we are
> at it since exception cannot be injected during vmentry anyway.
> 
> Signed-off-by: Gleb Natapov <gleb@redhat.com>
> ---
>  arch/x86/kvm/vmx.c | 8 +++-----
>  1 file changed, 3 insertions(+), 5 deletions(-)
> 
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index 663bc5e..5bfa09d 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -1902,12 +1902,11 @@ static void skip_emulated_instruction(struct kvm_vcpu *vcpu)
>   * a #PF exception (this is the only case in which KVM injects a #PF when L2
>   * is running).
>   */
> -static int nested_pf_handled(struct kvm_vcpu *vcpu)
> +static int nested_ex_handled(struct kvm_vcpu *vcpu, unsigned nr)
>  {
>  	struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
>  
> -	/* TODO: also check PFEC_MATCH/MASK, not just EB.PF. */

Just one more question, why drop this comment?  It doesn't seem
incorrect in the particular case where nr == PF_VECTOR.

> -	if (!(vmcs12->exception_bitmap & (1u << PF_VECTOR)))
> +	if (!(vmcs12->exception_bitmap & (1u << nr)))
>  		return 0;
>  
>  	nested_vmx_vmexit(vcpu);
> @@ -1921,8 +1920,7 @@ static void vmx_queue_exception(struct kvm_vcpu *vcpu, unsigned nr,
>  	struct vcpu_vmx *vmx = to_vmx(vcpu);
>  	u32 intr_info = nr | INTR_INFO_VALID_MASK;
>  
> -	if (!reinject && nr == PF_VECTOR && is_guest_mode(vcpu) &&
> -	    !vmx->nested.nested_run_pending && nested_pf_handled(vcpu))
> +	if (!reinject && is_guest_mode(vcpu) && nested_ex_handled(vcpu, nr))
>  		return;
>  
>  	if (has_error_code) {
>