From: Mike Christie mchristi@redhat.com
[ Upstream commit 887e975c4172d0d5670c39ead2f18ba1e4ec8133 ]
Fix bug added with the patch:
commit 8f3ea35929a0806ad1397db99a89ffee0140822a Author: Josef Bacik josef@toxicpanda.com Date: Mon Jul 16 12:11:35 2018 -0400
nbd: handle unexpected replies better
where if the timeout handler runs when the completion path is and we fail to grab the mutex in the timeout handler we will leave a config reference and cannot free the config later.
Reviewed-by: Josef Bacik josef@toxicpanda.com Signed-off-by: Mike Christie mchristi@redhat.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/block/nbd.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 57aebc6e1c288..5d5e52c6509ce 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -355,8 +355,10 @@ static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req, } config = nbd->config;
- if (!mutex_trylock(&cmd->lock)) + if (!mutex_trylock(&cmd->lock)) { + nbd_config_put(nbd); return BLK_EH_RESET_TIMER; + }
if (config->num_connections > 1) { dev_err_ratelimited(nbd_to_dev(nbd),