KVM: nVMX: reset cache/shadows when switching loaded VMCS

Reset the vm_{entry,exit}_controls_shadow variables as well as the
segment cache after loading a new VMCS in vmx_switch_vmcs().  The
shadows/cache track VMCS data, i.e. they're stale every time we
switch to a new VMCS regardless of reason.

This fixes a bug where stale control shadows would be consumed after
a nested VMExit due to a failed consistency check.
Suggested-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/vmx.c

@@ -10951,6 +10951,10 @@ static void vmx_switch_vmcs(struct kvm_vcpu *vcpu, struct loaded_vmcs *vmcs)
 	vmx->loaded_vmcs = vmcs;
 	vmx_vcpu_load(vcpu, cpu);
 	put_cpu();
+
+	vm_entry_controls_reset_shadow(vmx);
+	vm_exit_controls_reset_shadow(vmx);
+	vmx_segment_cache_clear(vmx);
 }
 
 /*
@@ -12642,7 +12646,6 @@ static int enter_vmx_non_root_mode(struct kvm_vcpu *vcpu, u32 *exit_qual)
 		vmx->nested.vmcs01_guest_bndcfgs = vmcs_read64(GUEST_BNDCFGS);
 
 	vmx_switch_vmcs(vcpu, &vmx->nested.vmcs02);
-	vmx_segment_cache_clear(vmx);
 
 	if (vmcs12->cpu_based_vm_exec_control & CPU_BASED_USE_TSC_OFFSETING)
 		vcpu->arch.tsc_offset += vmcs12->tsc_offset;
@@ -13471,9 +13474,6 @@ static void nested_vmx_vmexit(struct kvm_vcpu *vcpu, u32 exit_reason,
 	}
 
 	vmx_switch_vmcs(vcpu, &vmx->vmcs01);
-	vm_entry_controls_reset_shadow(vmx);
-	vm_exit_controls_reset_shadow(vmx);
-	vmx_segment_cache_clear(vmx);
 
 	/* Update any VMCS fields that might have changed while L2 ran */
 	vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, vmx->msr_autoload.host.nr);