aboutsummaryrefslogtreecommitdiff
path: root/hw/virtio/virtio.c
diff options
context:
space:
mode:
authorLaurent Vivier <lvivier@redhat.com>2020-07-27 17:33:19 +0200
committerMichael S. Tsirkin <mst@redhat.com>2020-07-27 11:34:50 -0400
commit0c9753ebda274b0e618d7b4032bb2d83d27483ed (patch)
treee289473b00bdbc7c56e248e640c09fdbfb2927e2 /hw/virtio/virtio.c
parentd0d89526f70ded5ac41a4c6bb071c0d919b772db (diff)
downloadqemu-0c9753ebda274b0e618d7b4032bb2d83d27483ed.zip
qemu-0c9753ebda274b0e618d7b4032bb2d83d27483ed.tar.gz
qemu-0c9753ebda274b0e618d7b4032bb2d83d27483ed.tar.bz2
virtio-pci: fix virtio_pci_queue_enabled()
In legacy mode, virtio_pci_queue_enabled() falls back to virtio_queue_enabled() to know if the queue is enabled. But virtio_queue_enabled() calls again virtio_pci_queue_enabled() if k->queue_enabled is set. This ends in a crash after a stack overflow. The problem can be reproduced with "-device virtio-net-pci,disable-legacy=off,disable-modern=true -net tap,vhost=on" And a look to the backtrace is very explicit: ... #4 0x000000010029a438 in virtio_queue_enabled () #5 0x0000000100497a9c in virtio_pci_queue_enabled () ... #130902 0x000000010029a460 in virtio_queue_enabled () #130903 0x0000000100497a9c in virtio_pci_queue_enabled () #130904 0x000000010029a460 in virtio_queue_enabled () #130905 0x0000000100454a20 in vhost_net_start () ... This patch fixes the problem by introducing a new function for the legacy case and calls it from virtio_pci_queue_enabled(). It also calls it from virtio_queue_enabled() to avoid code duplication. Fixes: f19bcdfedd53 ("virtio-pci: implement queue_enabled method") Cc: Jason Wang <jasowang@redhat.com> Cc: Cindy Lu <lulu@redhat.com> CC: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Laurent Vivier <lvivier@redhat.com> Message-Id: <20200727153319.43716-1-lvivier@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'hw/virtio/virtio.c')
-rw-r--r--hw/virtio/virtio.c7
1 files changed, 6 insertions, 1 deletions
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 546a198..e983025 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -3309,6 +3309,11 @@ hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n)
return vdev->vq[n].vring.desc;
}
+bool virtio_queue_enabled_legacy(VirtIODevice *vdev, int n)
+{
+ return virtio_queue_get_desc_addr(vdev, n) != 0;
+}
+
bool virtio_queue_enabled(VirtIODevice *vdev, int n)
{
BusState *qbus = qdev_get_parent_bus(DEVICE(vdev));
@@ -3317,7 +3322,7 @@ bool virtio_queue_enabled(VirtIODevice *vdev, int n)
if (k->queue_enabled) {
return k->queue_enabled(qbus->parent, n);
}
- return virtio_queue_get_desc_addr(vdev, n) != 0;
+ return virtio_queue_enabled_legacy(vdev, n);
}
hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n)