diff options
| author | Xiubo Li <xiubli@redhat.com> | 2020-10-13 22:45:14 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-11-05 11:43:22 +0100 |
| commit | 742fd49cf811ca164489e339b862e3fb8e240a73 (patch) | |
| tree | 7444e36cfdd1a5e49f03096227e54a08fe36b96d | |
| parent | b71dbaf08f9f5b8fafdeca143c7ed89ed62c1030 (diff) | |
| download | linux-stable-742fd49cf811ca164489e339b862e3fb8e240a73.tar.gz linux-stable-742fd49cf811ca164489e339b862e3fb8e240a73.tar.bz2 linux-stable-742fd49cf811ca164489e339b862e3fb8e240a73.zip | |
nbd: make the config put is called before the notifying the waiter
[ Upstream commit 87aac3a80af5cbad93e63250e8a1e19095ba0d30 ]
There has one race case for ceph's rbd-nbd tool. When do mapping
it may fail with EBUSY from ioctl(nbd, NBD_DO_IT), but actually
the nbd device has already unmaped.
It dues to if just after the wake_up(), the recv_work() is scheduled
out and defers calling the nbd_config_put(), though the map process
has exited the "nbd->recv_task" is not cleared.
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/block/nbd.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 7c577cabb9c3..742f8160b6e2 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -787,9 +787,9 @@ static void recv_work(struct work_struct *work) blk_mq_complete_request(blk_mq_rq_from_pdu(cmd)); } + nbd_config_put(nbd); atomic_dec(&config->recv_threads); wake_up(&config->recv_wq); - nbd_config_put(nbd); kfree(args); } |