At some point, after unplugging virtio-pci the virtio device may be unrealised,
but the memory regions may be present in flatview. So, it's a possible situation
when memory region's callbacks are called for "unplugged" device.
Previous two patches made sure this case does not cause QEMU to crash.
This patch adds check for "notify" memory region. Now reads will return "-1" if a virtio
device is not present on a virtio bus.
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=
1938042
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=
1743098
Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
Message-Id: <
20210609095843.141378-4-andrew@daynix.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
static uint64_t virtio_pci_notify_read(void *opaque, hwaddr addr,
unsigned size)
{
+ VirtIOPCIProxy *proxy = opaque;
+ if (virtio_bus_get_device(&proxy->bus) == NULL) {
+ return UINT64_MAX;
+ }
+
return 0;
}
uint64_t val;
if (vdev == NULL) {
- return 0;
+ return UINT64_MAX;
}
val = qatomic_xchg(&vdev->isr, 0);
uint64_t val;
if (vdev == NULL) {
- return 0;
+ return UINT64_MAX;
}
switch (size) {