From a1b0c1c64dfef0cff8555bb708bfc5d7c66c6ca4 Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Tue, 16 Oct 2018 18:50:07 +0200 Subject: x86/kvm/nVMX: allow bare VMXON state migration It is perfectly valid for a guest to do VMXON and not do VMPTRLD. This state needs to be preserved on migration. Cc: stable@vger.kernel.org Fixes: 8fcc4b5923af5de58b80b53a069453b135693304 Signed-off-by: Vitaly Kuznetsov Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 0b665c74fadc..5df47291ad4d 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -14827,13 +14827,6 @@ static int vmx_set_nested_state(struct kvm_vcpu *vcpu, if (!page_address_valid(vcpu, kvm_state->vmx.vmxon_pa)) return -EINVAL; - if (kvm_state->size < sizeof(kvm_state) + sizeof(*vmcs12)) - return -EINVAL; - - if (kvm_state->vmx.vmcs_pa == kvm_state->vmx.vmxon_pa || - !page_address_valid(vcpu, kvm_state->vmx.vmcs_pa)) - return -EINVAL; - if ((kvm_state->vmx.smm.flags & KVM_STATE_NESTED_SMM_GUEST_MODE) && (kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE)) return -EINVAL; @@ -14863,6 +14856,14 @@ static int vmx_set_nested_state(struct kvm_vcpu *vcpu, if (ret) return ret; + /* Empty 'VMXON' state is permitted */ + if (kvm_state->size < sizeof(kvm_state) + sizeof(*vmcs12)) + return 0; + + if (kvm_state->vmx.vmcs_pa == kvm_state->vmx.vmxon_pa || + !page_address_valid(vcpu, kvm_state->vmx.vmcs_pa)) + return -EINVAL; + set_current_vmptr(vmx, kvm_state->vmx.vmcs_pa); if (kvm_state->vmx.smm.flags & KVM_STATE_NESTED_SMM_VMXON) { -- cgit v1.2.1