From 0c165b3c01fefa78f440d5759cef47e8754a7a32 Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Mon, 8 Feb 2021 23:23:25 +0000 Subject: [PATCH] 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: David Woodhouse Message-Id: <20210208232326.1830370-1-dwmw2@infradead.org> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/xen.c | 38 ++++++++++++++++++++++++++++---------- 1 file changed, 28 insertions(+), 10 deletions(-) diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c index b08a688e56f9..af8f6562fce4 100644 --- a/arch/x86/kvm/xen.c +++ b/arch/x86/kvm/xen.c @@ -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); - r = 0; - } + 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; - r = 0; - } + 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; - r = 0; - } + else + data->u.gpa = GPA_INVALID; + r = 0; break; default: -- 2.11.0