Commit fa58a9fa authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

KVM: nVMX: include shadow vmcs12 in nested state 



The shadow vmcs12 cannot be flushed on KVM_GET_NESTED_STATE,
because at that point guest memory is assumed by userspace to
be immutable.  Capture the cache in vmx_get_nested_state, adding
another page at the end if there is an active shadow vmcs12.

Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 61ada748

arch/x86/kvm/vmx.c

+30 −1
Original line number Diff line number Diff line
@@ -13191,9 +13191,15 @@ static int vmx_get_nested_state(struct kvm_vcpu *vcpu, 
		kvm_state.vmx.vmxon_pa = vmx->nested.vmxon_ptr;

		kvm_state.vmx.vmcs_pa = vmx->nested.current_vmptr;



		if (vmx->nested.current_vmptr != -1ull)

		if (vmx->nested.current_vmptr != -1ull) {

			kvm_state.size += VMCS12_SIZE;



			if (is_guest_mode(vcpu) &&

			    nested_cpu_has_shadow_vmcs(vmcs12) &&

			    vmcs12->vmcs_link_pointer != -1ull)

				kvm_state.size += VMCS12_SIZE;

		}



		if (vmx->nested.smm.vmxon)

			kvm_state.vmx.smm.flags |= KVM_STATE_NESTED_SMM_VMXON;
@@ -13232,6 +13238,13 @@ static int vmx_get_nested_state(struct kvm_vcpu *vcpu, 
	if (copy_to_user(user_kvm_nested_state->data, vmcs12, sizeof(*vmcs12)))

		return -EFAULT;



	if (nested_cpu_has_shadow_vmcs(vmcs12) &&

	    vmcs12->vmcs_link_pointer != -1ull) {

		if (copy_to_user(user_kvm_nested_state->data + VMCS12_SIZE,

				 get_shadow_vmcs12(vcpu), sizeof(*vmcs12)))

			return -EFAULT;

	}



out:

	return kvm_state.size;

}
@@ -13316,6 +13329,22 @@ static int vmx_set_nested_state(struct kvm_vcpu *vcpu, 
	vmx->nested.nested_run_pending =

		!!(kvm_state->flags & KVM_STATE_NESTED_RUN_PENDING);



	if (nested_cpu_has_shadow_vmcs(vmcs12) &&

	    vmcs12->vmcs_link_pointer != -1ull) {

		struct vmcs12 *shadow_vmcs12 = get_shadow_vmcs12(vcpu);

		if (kvm_state->size < sizeof(kvm_state) + 2 * sizeof(*vmcs12))

			return -EINVAL;



		if (copy_from_user(shadow_vmcs12,

				   user_kvm_nested_state->data + VMCS12_SIZE,

				   sizeof(*vmcs12)))

			return -EFAULT;



		if (shadow_vmcs12->hdr.revision_id != VMCS12_REVISION ||

		    !shadow_vmcs12->hdr.shadow_vmcs)

			return -EINVAL;

	}



	if (check_vmentry_prereqs(vcpu, vmcs12) ||

	    check_vmentry_postreqs(vcpu, vmcs12, &exit_qual))

		return -EINVAL;