Re: [PATCH 9/9] Add VMEXIT handler and intercepts

[Avi Kivity <avi@qumranet.com>]

Alexander Graf wrote:
> This adds the #VMEXIT intercept, so we return to the level 1 guest
> when something happens in the level 2 guest that should return to
> the level 1 guest.
>
> @@ -223,6 +228,21 @@ static void svm_queue_exception(struct kvm_vcpu *vcpu, unsigned nr,
>  {
>  	struct vcpu_svm *svm = to_svm(vcpu);
>  
> +	/* If we are within a nested VM we'd better #VMEXIT and let the
> +	   guest handle the exception */
> +	if (is_nested(svm)) {
> +		svm->vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + nr;
> +		svm->vmcb->control.exit_code_hi = 0;
> +		svm->vmcb->control.exit_info_1 = error_code;
> +		svm->vmcb->control.exit_info_2 = svm->vcpu.arch.cr2;
>   

#vmexit isn't supposed to modify cr2, but we've corrupted it here.

> +		if (nested_svm_exit_handled(svm, false)) {
> +			nsvm_printk("VMexit -> EXCP 0x%x\n", nr);
> +
> +			nested_svm_vmexit(svm);
> +			return;
> +		}
> +	}
> +
>   

Please move the entire block into a separate function.


> +static int nested_svm_vmexit_real(struct vcpu_svm *svm, void *arg1,
> +				  void *arg2, void *opaque)
> +{
> +	struct vmcb *nested_vmcb = (struct vmcb *)arg1;
> +	struct vmcb *hsave = (struct vmcb *)arg2;
> +	u64 nested_save[] = { nested_vmcb->save.cr0,
> +			      nested_vmcb->save.cr3,
> +			      nested_vmcb->save.cr4,
> +			      nested_vmcb->save.efer,
> +			      nested_vmcb->control.intercept_cr_read,
> +			      nested_vmcb->control.intercept_cr_write,
> +			      nested_vmcb->control.intercept_dr_read,
> +			      nested_vmcb->control.intercept_dr_write,
> +			      nested_vmcb->control.intercept_exceptions,
> +			      nested_vmcb->control.intercept,
> +			      nested_vmcb->control.msrpm_base_pa,
> +			      nested_vmcb->control.iopm_base_pa,
> +			      nested_vmcb->control.tsc_offset };
> +
> +	/* Give the current vmcb to the guest */
> +	memcpy(nested_vmcb, svm->vmcb, sizeof(struct vmcb));
> +	nested_vmcb->save.cr0 = nested_save[0];
> +	if (!npt_enabled)
> +		nested_vmcb->save.cr3 = nested_save[1];
> +	nested_vmcb->save.cr4 = nested_save[2];
> +	nested_vmcb->save.efer = nested_save[3];
> +	nested_vmcb->control.intercept_cr_read = nested_save[4];
> +	nested_vmcb->control.intercept_cr_write = nested_save[5];
> +	nested_vmcb->control.intercept_dr_read = nested_save[6];
> +	nested_vmcb->control.intercept_dr_write = nested_save[7];
> +	nested_vmcb->control.intercept_exceptions = nested_save[8];
> +	nested_vmcb->control.intercept = nested_save[9];
> +	nested_vmcb->control.msrpm_base_pa = nested_save[10];
> +	nested_vmcb->control.iopm_base_pa = nested_save[11];
> +	nested_vmcb->control.tsc_offset = nested_save[12];
> +
> +	if ((nested_vmcb->control.int_ctl & V_IRQ_MASK) &&
> +	    (nested_vmcb->control.int_vector)) {
> +		nsvm_printk("WARNING: IRQ 0x%x still enabled on #VMEXIT\n",
> +				nested_vmcb->control.int_vector);
> +	}
> +
> +	/* Restore the original control entries */
> +	memcpy(&svm->vmcb->control, &hsave->control,
> +	       sizeof(struct vmcb_control_area));
> +	force_new_asid(&svm->vcpu);
> +	/* Kill any pending exceptions */
> +	if (svm->vcpu.arch.exception.pending == true)
> +		nsvm_printk("WARNING: Pending Exception\n");
>   

This should set control.exit_int_info.

-- 
error compiling committee.c: too many arguments to function