KVM: nVMX: check vmcs12 for valid activity state

KVM does not use the activity state VMCS field, and does not support
it in nested VMX either (the corresponding bits in the misc VMX feature
MSR are zero).  Fail entry if the activity state is set to anything but
"active".

Since the value will always be the same for L1 and L2, we do not need
to read and write the corresponding VMCS field on L1/L2 transitions,
either.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 5a87a58af49dc75b61de4f89b1886d74f86dd3a7..8d52bcf371df587f09a0c48ae193ae1b7980e809 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -7106,7 +7106,6 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
                vmcs12->vm_entry_instruction_len);
        vmcs_write32(GUEST_INTERRUPTIBILITY_INFO,
                vmcs12->guest_interruptibility_info);
-       vmcs_write32(GUEST_ACTIVITY_STATE, vmcs12->guest_activity_state);
        vmcs_write32(GUEST_SYSENTER_CS, vmcs12->guest_sysenter_cs);
        kvm_set_dr(vcpu, 7, vmcs12->guest_dr7);
        vmcs_writel(GUEST_RFLAGS, vmcs12->guest_rflags);
@@ -7325,6 +7324,11 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch)
                return 1;
        }
 
+       if (vmcs12->guest_activity_state != GUEST_ACTIVITY_ACTIVE) {
+               nested_vmx_failValid(vcpu, VMXERR_ENTRY_INVALID_CONTROL_FIELD);
+               return 1;
+       }
+
        if ((vmcs12->cpu_based_vm_exec_control & CPU_BASED_USE_MSR_BITMAPS) &&
                        !IS_ALIGNED(vmcs12->msr_bitmap, PAGE_SIZE)) {
                /*TODO: Also verify bits beyond physical address width are 0*/
@@ -7555,7 +7559,6 @@ static void prepare_vmcs12(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
        vmcs12->guest_gdtr_base = vmcs_readl(GUEST_GDTR_BASE);
        vmcs12->guest_idtr_base = vmcs_readl(GUEST_IDTR_BASE);
 
-       vmcs12->guest_activity_state = vmcs_read32(GUEST_ACTIVITY_STATE);
        vmcs12->guest_interruptibility_info =
                vmcs_read32(GUEST_INTERRUPTIBILITY_INFO);
        vmcs12->guest_pending_dbg_exceptions =