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Subject: Re: [PATCH -next 8/8] block: fix null-pointer dereference in
 ioc_pd_init
To:     Christoph Hellwig <hch@infradead.org>, Li Nan <linan122@huawei.com>
Cc:     tj@kernel.org, josef@toxicpanda.com, axboe@kernel.dk,
        cgroups@vger.kernel.org, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, yi.zhang@huawei.com,
        "yukuai (C)" <yukuai3@huawei.com>
References: <20221128154434.4177442-1-linan122@huawei.com>
 <20221128154434.4177442-9-linan122@huawei.com>
 <Y4YWQcb4PMmIdzIM@infradead.org>
From:   Yu Kuai <yukuai1@huaweicloud.com>
Message-ID: <e46fdde5-f320-9276-72ec-0f5fb5b48ffd@huaweicloud.com>
Date:   Wed, 30 Nov 2022 09:32:58 +0800
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Hi,

?? 2022/11/29 22:25, Christoph Hellwig д??:
> On Mon, Nov 28, 2022 at 11:44:34PM +0800, Li Nan wrote:
>> Fix problem by moving rq_qos_exit() to disk_release().
> 
> No, that now means it is removed to later.  You need to add proper
> synchronization.
> .
> 

Can you explain a bit more? Maybe I'm being noob, here disk is about to
be freed, and I can think of any contention.

Thanks,
Kuai