path: root/block
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authorYu Kuai <>2021-08-05 20:46:45 +0800
committerJens Axboe <>2021-08-05 11:18:13 -0600
commit8d75d0eff6887bcac7225e12b9c75595e523d92d (patch)
tree99e3d91a3d183cd62f22ad87b036e9f3d02dc631 /block
parentcc396d27d8d5884bbb555efd7783b9e9e2b41dc2 (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 <> Acked-by: Tejun Heo <> Link: Signed-off-by: Jens Axboe <>
Diffstat (limited to 'block')
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;
+ }