From cd7d1d26b0a333bf2fca715e332690bbd738c097 Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Tue, 19 Aug 2014 12:56:29 +0800 Subject: vhost_net: start/stop guest notifiers properly commit a9f98bb5ebe6fb1869321dcc58e72041ae626ad8 "vhost: multiqueue support" changed the order of stopping the device. Previously vhost_dev_stop would disable backend and only afterwards, unset guest notifiers. We now unset guest notifiers while vhost is still active. This can lose interrupts causing guest networking to fail. In particular, this has been observed during migration. To fix this, several other changes are needed: - remove the hdev->started assertion in vhost.c since we may want to start the guest notifiers before vhost starts and stop the guest notifiers after vhost is stopped. - introduce the vhost_net_set_vq_index() and call it before setting guest notifiers. This is to guarantee vhost_net has the correct virtqueue index when setting guest notifiers. MST: fix up error handling. Cc: qemu-stable@nongnu.org Cc: Jason Wang Signed-off-by: Michael S. Tsirkin Tested-by: Andrey Korolyov Reported-by: "Zhangjie (HZ)" Tested-by: William Dauchy Signed-off-by: Jason Wang Reviewed-by: Michael S. Tsirkin --- hw/virtio/vhost.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'hw/virtio/vhost.c') diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c index e55fe1cc7e..5d7c40ac04 100644 --- a/hw/virtio/vhost.c +++ b/hw/virtio/vhost.c @@ -976,7 +976,6 @@ void vhost_dev_disable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev) bool vhost_virtqueue_pending(struct vhost_dev *hdev, int n) { struct vhost_virtqueue *vq = hdev->vqs + n - hdev->vq_index; - assert(hdev->started); assert(n >= hdev->vq_index && n < hdev->vq_index + hdev->nvqs); return event_notifier_test_and_clear(&vq->masked_notifier); } @@ -988,7 +987,6 @@ void vhost_virtqueue_mask(struct vhost_dev *hdev, VirtIODevice *vdev, int n, struct VirtQueue *vvq = virtio_get_queue(vdev, n); int r, index = n - hdev->vq_index; - assert(hdev->started); assert(n >= hdev->vq_index && n < hdev->vq_index + hdev->nvqs); struct vhost_vring_file file = { -- cgit v1.2.1