On 22/08/2018 16:57, Fam Zheng wrote:
> On master (13b7b188501) and v3.0.0, booting the OpenBSD install63.iso with a
> virtio-net (slirp backend) device gives this assertion failure:
>
> (gdb) bt
> #0 0x00007f6f25703feb in raise () at /lib64/libc.so.6
> #1 0x00007f6f256ee5c1 in abort () at /lib64/libc.so.6
> #2 0x00007f6f256ee491 in _nl_load_domain.cold.0 () at /lib64/libc.so.6
> #3 0x00007f6f256fc752 in () at /lib64/libc.so.6
> #4 0x000055d966f5b5d6 in address_space_stw_le_cached (cache=0x7f6f040fd700,
> addr=516, val=1, attrs=..., result=0x0)
> at /stor/work/qemu/include/exec/memory_ldst_cached.inc.h:85
Does this help?
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index d4e4d98b59..5982678c75 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -2006,14 +2006,25 @@ static int virtio_set_features_nocheck(VirtIODevice
*vdev, uint64_t val)
int virtio_set_features(VirtIODevice *vdev, uint64_t val)
{
- /*
+ int ret;
+ /*
* The driver must not attempt to set features after feature negotiation
* has finished.
*/
if (vdev->status & VIRTIO_CONFIG_S_FEATURES_OK) {
return -EINVAL;
}
- return virtio_set_features_nocheck(vdev, val);
+ ret = virtio_set_features_nocheck(vdev, val);
+ if (!ret && (val & VIRTIO_RING_F_EVENT_IDX)) {
+ /* VIRTIO_RING_F_EVENT_IDX changes the size of the caches. */
+ int i;
+ for (i = 0; i < VIRTIO_QUEUE_MAX; i++) {
+ if (vdev->vq[i].vring.num != 0) {
+ virtio_init_region_cache(vdev, i);
+ }
+ }
+ }
+ return ret;
}
int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id)
(I haven't tried to reproduce, or checked the spec to see if this could
be a guest bug too. Of course assertion failures are wrong anyway, so
we might as well work around it as above).
Paolo
