KVM: arm/arm64: check power_off in critical section before VCPU run

In case a vcpu off PSCI call is called just after we executed the
vcpu_sleep check, we can enter the guest although power_off
is set. Let's check the power_off state in the critical section,
just before entering the guest.

Signed-off-by: Eric Auger <[e-mail]>
Reported-by: Christoffer Dall <[e-mail]>
Reviewed-by: Christoffer Dall <[e-mail]>
Signed-off-by: Christoffer Dall <[e-mail]>

arch/arm/kvm/arm.c

···
 			run->exit_reason = KVM_EXIT_INTR;
 		}
 
-		if (ret <= 0 || need_new_vmid_gen(vcpu->kvm)) {
+		if (ret <= 0 || need_new_vmid_gen(vcpu->kvm) ||
+			vcpu->arch.power_off) {
 			local_irq_enable();
 			kvm_timer_sync_hwstate(vcpu);
 			kvm_vgic_sync_hwstate(vcpu);