From: Stefan Hajnoczi <[email protected]> virtio_error() calls virtio_notify_config() to inject a VIRTIO Configuration Change Notification. This doesn't work from IOThreads because the BQL is not held and the interrupt code path requires the BQL.
Follow the same approach as virtio_notify() and use ->config_notifier (an irqfd) when called from the IOThread. Signed-off-by: Stefan Hajnoczi <[email protected]> Reviewed-by: Michael S. Tsirkin <[email protected]> Message-ID: <[email protected]> Signed-off-by: Michael S. Tsirkin <[email protected]> --- hw/virtio/virtio.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 6ce5823898..de89e8104a 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -2706,7 +2706,12 @@ void virtio_notify_config(VirtIODevice *vdev) virtio_set_isr(vdev, 0x3); vdev->generation++; - virtio_notify_vector(vdev, vdev->config_vector); + + if (qemu_in_iothread()) { + defer_call(virtio_notify_irqfd_deferred_fn, &vdev->config_notifier); + } else { + virtio_notify_vector(vdev, vdev->config_vector); + } } static bool virtio_device_endian_needed(void *opaque) -- MST
