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Subject: Re: [PATCH] block: revert pushing the final release of request_queue
 to a workqueue.
From:   "yukuai (C)" <yukuai3@huawei.com>
To:     Ming Lei <ming.lei@redhat.com>
CC:     <axboe@kernel.dk>, <chaitanya.kulkarni@wdc.com>,
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References: <20200206111052.45356-1-yukuai3@huawei.com>
 <20200207093012.GA5905@ming.t460p>
 <1f2fb027-1d62-2a52-9956-7847fa1baf96@huawei.com>
Message-ID: <63873791-e303-aece-94c5-efb2a6976363@huawei.com>
Date:   Fri, 7 Feb 2020 20:24:59 +0800
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On 2020/2/7 18:26, yukuai (C) wrote:
> The reason of the problem is because the final release of request_queue
> may be called after loop_remove() returns.

The description is not accurate. The reason of the problem is that
__blk_trace_setup() called before the final release of request_queue
returns.(step 4 before step 5)

Thanks!
Yu Kuai