vhost: allow batching hint without size

Commit e2ae38cf3d ("vhost: fix hung thread due to erroneous iotlb
entries") tries to reject the IOTLB message whose size is zero. But
the size is not necessarily meaningful, one example is the batching
hint, so the commit breaks that.

Fixing this be reject zero size message only if the message is used to
update/invalidate the IOTLB.

Fixes: e2ae38cf3d ("vhost: fix hung thread due to erroneous iotlb entries")
Reported-by: Eli Cohen <elic@nvidia.com>
Cc: Anirudh Rayabharam <mail@anirudhrb.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20220310075211.4801-1-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Eli Cohen <elic@nvidia.com>
This commit is contained in:
Jason Wang 2022-03-10 15:52:11 +08:00 committed by Michael S. Tsirkin
parent 3dd7d135e7
commit 95932ab2ea

View File

@ -1170,7 +1170,9 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev,
goto done;
}
if (msg.size == 0) {
if ((msg.type == VHOST_IOTLB_UPDATE ||
msg.type == VHOST_IOTLB_INVALIDATE) &&
msg.size == 0) {
ret = -EINVAL;
goto done;
}