diff options
| author | Yu Kuai <yukuai3@huawei.com> | 2021-08-05 20:46:45 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2021-08-05 11:18:13 -0600 |
| commit | 8d75d0eff6887bcac7225e12b9c75595e523d92d (patch) | |
| tree | 99e3d91a3d183cd62f22ad87b036e9f3d02dc631 | |
| parent | cc396d27d8d5884bbb555efd7783b9e9e2b41dc2 (diff) | |
blk-iolatency: error out if blk_get_queue() failed in iolatency_set_limit()
If queue is dying while iolatency_set_limit() is in progress,
blk_get_queue() won't increment the refcount of the queue. However,
blk_put_queue() will still decrement the refcount later, which will
cause the refcout to be unbalanced.
Thus error out in such case to fix the problem.
Fixes: 8c772a9bfc7c ("blk-iolatency: fix IO hang due to negative inflight counter")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20210805124645.543797-1-yukuai3@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | block/blk-iolatency.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/block/blk-iolatency.c b/block/blk-iolatency.c index 81be0096411d..d8b0d8bd132b 100644 --- a/block/blk-iolatency.c +++ b/block/blk-iolatency.c @@ -833,7 +833,11 @@ static ssize_t iolatency_set_limit(struct kernfs_open_file *of, char *buf, enable = iolatency_set_min_lat_nsec(blkg, lat_val); if (enable) { - WARN_ON_ONCE(!blk_get_queue(blkg->q)); + if (!blk_get_queue(blkg->q)) { + ret = -ENODEV; + goto out; + } + blkg_get(blkg); } |