[PULL 04/15] s390x: adapter routes error handling

[Cornelia Huck <cohuck@redhat.com>]

If the kernel irqchip has been disabled, we don't want the
{add,release}_adapter_routes routines to call any kvm_irqchip_*
interfaces, as they may rely on an irqchip actually having been
created. Just take a quick exit in that case instead. If you are
trying to use irqfd without a kernel irqchip, we will fail with
an error.

Also initialize routes->gsi[] with -1 in the virtio-ccw handling,
to make sure we don't trip over other errors, either. (Nobody
else uses the gsi array in that structure.)

Fixes: d426d9fba8ea ("s390x/virtio-ccw: wire up irq routing and irqfds")
Reviewed-by: Thomas Huth <thuth@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-Id: <20200117111147.5006-1-cohuck@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
---
 hw/intc/s390_flic_kvm.c | 8 ++++++++
 hw/s390x/virtio-ccw.c   | 4 ++++
 2 files changed, 12 insertions(+)

diff --git a/hw/intc/s390_flic_kvm.c b/hw/intc/s390_flic_kvm.c
index 2e1e70c61d5b..a306b26faa07 100644
--- a/hw/intc/s390_flic_kvm.c
+++ b/hw/intc/s390_flic_kvm.c
@@ -331,6 +331,10 @@ static int kvm_s390_add_adapter_routes(S390FLICState *fs,
     int ret, i;
     uint64_t ind_offset = routes->adapter.ind_offset;
 
+    if (!kvm_gsi_routing_enabled()) {
+        return -ENOSYS;
+    }
+
     for (i = 0; i < routes->num_routes; i++) {
         ret = kvm_irqchip_add_adapter_route(kvm_state, &routes->adapter);
         if (ret < 0) {
@@ -358,6 +362,10 @@ static void kvm_s390_release_adapter_routes(S390FLICState *fs,
 {
     int i;
 
+    if (!kvm_gsi_routing_enabled()) {
+        return;
+    }
+
     for (i = 0; i < routes->num_routes; i++) {
         if (routes->gsi[i] >= 0) {
             kvm_irqchip_release_virq(kvm_state, routes->gsi[i]);
diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c
index 6580ce5907dd..13f57e7b67f1 100644
--- a/hw/s390x/virtio-ccw.c
+++ b/hw/s390x/virtio-ccw.c
@@ -697,6 +697,7 @@ static void virtio_ccw_device_realize(VirtioCcwDevice *dev, Error **errp)
     CCWDeviceClass *ck = CCW_DEVICE_GET_CLASS(ccw_dev);
     SubchDev *sch;
     Error *err = NULL;
+    int i;
 
     sch = css_create_sch(ccw_dev->devno, errp);
     if (!sch) {
@@ -717,6 +718,9 @@ static void virtio_ccw_device_realize(VirtioCcwDevice *dev, Error **errp)
     ccw_dev->sch = sch;
     dev->indicators = NULL;
     dev->revision = -1;
+    for (i = 0; i < ADAPTER_ROUTES_MAX_GSI; i++) {
+        dev->routes.gsi[i] = -1;
+    }
     css_sch_build_virtual_schib(sch, 0, VIRTIO_CCW_CHPID_TYPE);
 
     trace_virtio_ccw_new_device(
-- 
2.21.1