From: Christian Borntraeger <borntraeger@de.ibm.com>
Date: Thu, 30 Jan 2020 16:18:28 +0000 (-0500)
Subject: KVM: s390: protvirt: do not inject interrupts after start
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=72f218208fa63806ebcfca7e793b095d346ee0a4;p=linux.git

KVM: s390: protvirt: do not inject interrupts after start

As PSW restart is handled by the ultravisor (and we only get a start
notification) we must re-check the PSW after a start before injecting
interrupts.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
---

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 66ba6ca714fba..fed025ea6f62a 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -4515,6 +4515,13 @@ int kvm_s390_vcpu_start(struct kvm_vcpu *vcpu)
 	}
 
 	kvm_s390_clear_cpuflags(vcpu, CPUSTAT_STOPPED);
+	/*
+	 * The real PSW might have changed due to a RESTART interpreted by the
+	 * ultravisor. We block all interrupts and let the next sie exit
+	 * refresh our view.
+	 */
+	if (kvm_s390_pv_cpu_is_protected(vcpu))
+		vcpu->arch.sie_block->gpsw.mask &= ~PSW_INT_MASK;
 	/*
 	 * Another VCPU might have used IBS while we were offline.
 	 * Let's play safe and flush the VCPU at startup.