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Sender: Tejun Heo <htejun@gmail.com>
Date:   Thu, 1 Dec 2022 00:11:46 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Yu Kuai <yukuai1@huaweicloud.com>
Cc:     Li Nan <linan122@huawei.com>, 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>
Subject: Re: [PATCH -next v2 8/9] block: fix null-pointer dereference in
 ioc_pd_init
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On Thu, Dec 01, 2022 at 10:12:13AM +0800, Yu Kuai wrote:
> 1) By mentioning that "del_gendisk() is quiescing the queue", do you
> suggest to add rcu_read_lock()? This seems wrong because blk_iocost_init
> requires memory allocation.

Quiescing uses SRCU so that should be fine but I'm not sure whether this is
the right one to piggyback on. Jens should have a better idea.

Thanks.

-- 
tejun