KVM: nVMX: sync vmcs02 segment regs prior to vmx_set_cr0
Segment registers must be synchronized prior to any code that may
trigger a call to emulation_required()/guest_state_valid(), e.g.
vmx_set_cr0(). Because preparing vmcs02 writes segmentation fields
directly, i.e. doesn't use vmx_set_segment(), emulation_required
will not be re-evaluated when synchronizing the segment registers,
which can result in L0 incorrectly starting emulation of L2.
Fixes: 8665c3f97320 ("KVM: nVMX: initialize descriptor cache fields in prepare_vmcs02_full")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
[Move all of prepare_vmcs02_full earlier, not just segment registers. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 051dab7..f0fd50b 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -10704,6 +10704,11 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
struct vcpu_vmx *vmx = to_vmx(vcpu);
u32 exec_control, vmcs12_exec_ctrl;
+ if (vmx->nested.dirty_vmcs12) {
+ prepare_vmcs02_full(vcpu, vmcs12, from_vmentry);
+ vmx->nested.dirty_vmcs12 = false;
+ }
+
/*
* First, the fields that are shadowed. This must be kept in sync
* with vmx_shadow_fields.h.
@@ -10941,11 +10946,6 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
/* Note: modifies VM_ENTRY/EXIT_CONTROLS and GUEST/HOST_IA32_EFER */
vmx_set_efer(vcpu, vcpu->arch.efer);
- if (vmx->nested.dirty_vmcs12) {
- prepare_vmcs02_full(vcpu, vmcs12, from_vmentry);
- vmx->nested.dirty_vmcs12 = false;
- }
-
/* Shadow page tables on either EPT or shadow page tables. */
if (nested_vmx_load_cr3(vcpu, vmcs12->guest_cr3, nested_cpu_has_ept(vmcs12),
entry_failure_code))