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From:   Jens Axboe <axboe@kernel.dk>
To:     tj@kernel.org, hch@lst.de, josef@toxicpanda.com,
        Yu Kuai <yukuai1@huaweicloud.com>
Cc:     cgroups@vger.kernel.org, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, yukuai3@huawei.com,
        yi.zhang@huawei.com, yangerkun@huawei.com
In-Reply-To: <20230414084008.2085155-1-yukuai1@huaweicloud.com>
References: <20230414084008.2085155-1-yukuai1@huaweicloud.com>
Subject: Re: [PATCH for-6.4/block] block/rq_qos: protect rq_qos apis with a
 new lock
Message-Id: <168486203985.398377.17593981162726402548.b4-ty@kernel.dk>
Date:   Tue, 23 May 2023 11:13:59 -0600
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On Fri, 14 Apr 2023 16:40:08 +0800, Yu Kuai wrote:
> commit 50e34d78815e ("block: disable the elevator int del_gendisk")
> move rq_qos_exit() from disk_release() to del_gendisk(), this will
> introduce some problems:
> 
> 1) If rq_qos_add() is triggered by enabling iocost/iolatency through
>    cgroupfs, then it can concurrent with del_gendisk(), it's not safe to
>    write 'q->rq_qos' concurrently.
> 
> [...]

Applied, thanks!

[1/1] block/rq_qos: protect rq_qos apis with a new lock
      commit: a13bd91be22318768d55470cbc0b0f4488ef9edf

Best regards,
-- 
Jens Axboe