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From:   Christoph Hellwig <hch@infradead.org>
To:     Yufen Yu <yuyufen@huawei.com>
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Subject: Re: [PATCH v4 0/6] bdi: fix use-after-free for bdi device
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Looking through this series the whoe approach of using a lock to clear
the ->dev pointer looks rather odd to me.  What is the reason for now
simply adding a separately allocated name field to struct
backing_dev_info that the name is copied to on allocation, and then
the ->dev field is not relevant for name printing and we don't need
to copy out the name in the potentionally more fast path callers that
want to print it?