diff options
| author | Jason Wang <jasowang@redhat.com> | 2018-01-23 12:27:25 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-01-25 00:55:37 +0300 |
| commit | e9cb4239134c860e5f92c75bf5321bd377bb505b (patch) | |
| tree | 07574c95ec8663139c964f4355c559ee27b379f8 | |
| parent | b7051cb8dadd69f85da5989017af2bb35b418950 (diff) | |
| download | linux-e9cb4239134c860e5f92c75bf5321bd377bb505b.tar.xz | |
vhost: use mutex_lock_nested() in vhost_dev_lock_vqs()
We used to call mutex_lock() in vhost_dev_lock_vqs() which tries to
hold mutexes of all virtqueues. This may confuse lockdep to report a
possible deadlock because of trying to hold locks belong to same
class. Switch to use mutex_lock_nested() to avoid false positive.
Fixes: 6b1e6cc7855b0 ("vhost: new device IOTLB API")
Reported-by: syzbot+dbb7c1161485e61b0241@syzkaller.appspotmail.com
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/vhost/vhost.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 33ac2b186b85..549771a0cd8b 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -904,7 +904,7 @@ static void vhost_dev_lock_vqs(struct vhost_dev *d) { int i = 0; for (i = 0; i < d->nvqs; ++i) - mutex_lock(&d->vqs[i]->mutex); + mutex_lock_nested(&d->vqs[i]->mutex, i); } static void vhost_dev_unlock_vqs(struct vhost_dev *d) |