Commit 0c165b3c authored by David Woodhouse's avatar David Woodhouse Committed by Paolo Bonzini
Browse files

KVM: x86/xen: Allow reset of Xen attributes 



In order to support Xen SHUTDOWN_soft_reset (for guest kexec, etc.) the
VMM needs to be able to tear everything down and return the Xen features
to a clean slate.

Signed-off-by: default avatarDavid Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20210208232326.1830370-1-dwmw2@infradead.org>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 8f5c44f9

arch/x86/kvm/xen.c

+28 −10
Original line number Diff line number Diff line
@@ -116,12 +116,17 @@ int kvm_xen_hvm_set_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data) 
		break;



	case KVM_XEN_ATTR_TYPE_SHARED_INFO:

		if (data->u.shared_info.gfn == GPA_INVALID) {

			kvm->arch.xen.shinfo_set = false;

			r = 0;

			break;

		}

		r = kvm_xen_shared_info_init(kvm, data->u.shared_info.gfn);

		break;





	case KVM_XEN_ATTR_TYPE_UPCALL_VECTOR:

		if (data->u.vector < 0x10)

		if (data->u.vector && data->u.vector < 0x10)

			r = -EINVAL;

		else {

			kvm->arch.xen.upcall_vector = data->u.vector;
@@ -150,10 +155,11 @@ int kvm_xen_hvm_get_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data) 
		break;



	case KVM_XEN_ATTR_TYPE_SHARED_INFO:

		if (kvm->arch.xen.shinfo_set) {

		if (kvm->arch.xen.shinfo_set)

			data->u.shared_info.gfn = gpa_to_gfn(kvm->arch.xen.shinfo_cache.gpa);

		else

			data->u.shared_info.gfn = GPA_INVALID;

		r = 0;

		}

		break;



	case KVM_XEN_ATTR_TYPE_UPCALL_VECTOR:
@@ -182,6 +188,11 @@ int kvm_xen_vcpu_set_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data) 
		BUILD_BUG_ON(sizeof(struct vcpu_info) !=

			     sizeof(struct compat_vcpu_info));



		if (data->u.gpa == GPA_INVALID) {

			vcpu->arch.xen.vcpu_info_set = false;

			break;

		}



		r = kvm_gfn_to_hva_cache_init(vcpu->kvm,

					      &vcpu->arch.xen.vcpu_info_cache,

					      data->u.gpa,
@@ -193,6 +204,11 @@ int kvm_xen_vcpu_set_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data) 
		break;



	case KVM_XEN_VCPU_ATTR_TYPE_VCPU_TIME_INFO:

		if (data->u.gpa == GPA_INVALID) {

			vcpu->arch.xen.vcpu_time_info_set = false;

			break;

		}



		r = kvm_gfn_to_hva_cache_init(vcpu->kvm,

					      &vcpu->arch.xen.vcpu_time_info_cache,

					      data->u.gpa,
@@ -220,17 +236,19 @@ int kvm_xen_vcpu_get_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data) 


	switch (data->type) {

	case KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO:

		if (vcpu->arch.xen.vcpu_info_set) {

		if (vcpu->arch.xen.vcpu_info_set)

			data->u.gpa = vcpu->arch.xen.vcpu_info_cache.gpa;

		else

			data->u.gpa = GPA_INVALID;

		r = 0;

		}

		break;



	case KVM_XEN_VCPU_ATTR_TYPE_VCPU_TIME_INFO:

		if (vcpu->arch.xen.vcpu_time_info_set) {

		if (vcpu->arch.xen.vcpu_time_info_set)

			data->u.gpa = vcpu->arch.xen.vcpu_time_info_cache.gpa;

		else

			data->u.gpa = GPA_INVALID;

		r = 0;

		}

		break;



	default: