KVM: VMX: Set msr bitmap correctly if vcpu is in guest mode

In commit 3af18d9c5fe9 ("KVM: nVMX: Prepare for using hardware MSR bitmap"),
we are setting MSR_BITMAP in prepare_vmcs02 if we should use hardware. This
is not enough since the field will be modified by following vmx_set_efer.

Fix this by setting vmx_msr_bitmap_nested in vmx_set_msr_bitmap if vcpu is
in guest mode.

Signed-off-by: Wincy Van <fanwenyi0529@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index f7b20b4..10a481b 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2168,7 +2168,10 @@ static void vmx_set_msr_bitmap(struct kvm_vcpu *vcpu)
 {
        unsigned long *msr_bitmap;
 
-       if (irqchip_in_kernel(vcpu->kvm) && apic_x2apic_mode(vcpu->arch.apic)) {
+       if (is_guest_mode(vcpu))
+               msr_bitmap = vmx_msr_bitmap_nested;
+       else if (irqchip_in_kernel(vcpu->kvm) &&
+               apic_x2apic_mode(vcpu->arch.apic)) {
                if (is_long_mode(vcpu))
                        msr_bitmap = vmx_msr_bitmap_longmode_x2apic;
                else
@@ -9218,9 +9221,9 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
        }
 
        if (cpu_has_vmx_msr_bitmap() &&
-           exec_control & CPU_BASED_USE_MSR_BITMAPS &&
-           nested_vmx_merge_msr_bitmap(vcpu, vmcs12)) {
-               vmcs_write64(MSR_BITMAP, __pa(vmx_msr_bitmap_nested));
+           exec_control & CPU_BASED_USE_MSR_BITMAPS) {
+               nested_vmx_merge_msr_bitmap(vcpu, vmcs12);
+               /* MSR_BITMAP will be set by following vmx_set_efer. */
        } else
                exec_control &= ~CPU_BASED_USE_MSR_BITMAPS;