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 11:08:45 +0100 |
| commit | 2ef6f4bd60411934e3fc2715442c2afe70f84bf3 (patch) | |
| tree | aa3b51d8b8ea3eca4c7b4cf236fd4e5c41d0209f /drivers/block | |
| parent | c151f68411cdeac5d70b48a19758d20ab110e4cc (diff) | |
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>
Diffstat (limited to 'drivers/block')
| -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 d7c7232e438c..52e1e71e8124 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -740,9 +740,9 @@ 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); } |