When a live migration is started the log address to mark dirty pages is provided
to the vhost backend through the vhost_dev_set_log function.
This function is called for each queue pairs but the queue index provided to the
vhost_virtqueue_set_addr function is wrongly set: always set to the first queue
pair. Then vhost backend lost descriptor addresses of the queue pairs greater
than 1 and behaviour of the vhost backend is unpredictable.
The vhost_dev_set_log is modified to provide the correct queue index to the
vhost_virtqueue_set_addr function that calls internally the vhost_get_vq_index
to compute the expected vhost_vq_index for vhost kernel and vhost user.
This change implies a modification of the vhost_virtqueue_start function to
provide the index and not the vhost_vq_index.
Signed-off-by: Thibaut Collet <thibaut.col...@6wind.com>
---
hw/virtio/vhost.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index feeaaa4..9311832 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -628,8 +628,9 @@ static int vhost_virtqueue_set_addr(struct vhost_dev *dev,
struct vhost_virtqueue *vq,
unsigned idx, bool enable_log)
{
+ int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, idx);
struct vhost_vring_addr addr = {
- .index = idx,
+ .index = vhost_vq_index,
.desc_user_addr = (uint64_t)(unsigned long)vq->desc,
.avail_user_addr = (uint64_t)(unsigned long)vq->avail,
.used_user_addr = (uint64_t)(unsigned long)vq->used,
@@ -662,7 +663,7 @@ static int vhost_dev_set_log(struct vhost_dev *dev, bool
enable_log)
goto err_features;
}
for (i = 0; i < dev->nvqs; ++i) {
- r = vhost_virtqueue_set_addr(dev, dev->vqs + i, i,
+ r = vhost_virtqueue_set_addr(dev, dev->vqs + i, dev->vq_index + i,
enable_log);
if (r < 0) {
goto err_vq;
@@ -671,7 +672,7 @@ static int vhost_dev_set_log(struct vhost_dev *dev, bool
enable_log)
return 0;
err_vq:
for (; i >= 0; --i) {
- t = vhost_virtqueue_set_addr(dev, dev->vqs + i, i,
+ t = vhost_virtqueue_set_addr(dev, dev->vqs + i, dev->vq_index + i,
dev->log_enabled);
assert(t >= 0);
}
@@ -836,7 +837,7 @@ static int vhost_virtqueue_start(struct vhost_dev *dev,
goto fail_alloc_ring;
}
- r = vhost_virtqueue_set_addr(dev, vq, vhost_vq_index, dev->log_enabled);
+ r = vhost_virtqueue_set_addr(dev, vq, idx, dev->log_enabled);
if (r < 0) {
r = -errno;
goto fail_alloc;
--
2.1.4
