Re: [PATCH] blk-iolatency: error out if blk_get_queue() failed in iolatency_set_limit()

On Thu, Aug 05, 2021 at 08:46:45PM +0800, Yu Kuai wrote:

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 <redacted>

Acked-by: Tejun Heo <tj@kernel.org>

Thanks.

-- 
tejun