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Date:   Wed, 30 Nov 2022 07:59:41 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Yu Kuai <yukuai1@huaweicloud.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Li Nan <linan122@huawei.com>, 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>
Subject: Re: [PATCH -next 8/8] block: fix null-pointer dereference in
 ioc_pd_init
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References: <20221128154434.4177442-1-linan122@huawei.com>
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 <Y4YWQcb4PMmIdzIM@infradead.org>
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On Wed, Nov 30, 2022 at 09:32:58AM +0800, Yu Kuai wrote:
> > 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.

Right now we need synchronization with e.g. open_mutex and a check
for a dead disk, which I suggst to add insted of creating a lifetime
imbalance.