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Date:   Fri, 21 May 2021 08:23:01 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Coly Li <colyli@suse.de>
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Subject: Re: [PATCH 12/26] bcache: convert to
 blk_alloc_disk/blk_cleanup_disk
Message-ID: <20210521062301.GA10244@lst.de>
References: <20210521055116.1053587-1-hch@lst.de> <20210521055116.1053587-13-hch@lst.de> <d4f1c005-2ce0-51b5-c861-431f0ffb3dcf@suse.de>
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On Fri, May 21, 2021 at 02:15:32PM +0800, Coly Li wrote:
> The  above 2 lines are added on purpose to prevent an refcount
> underflow. It is from commit 86da9f736740 ("bcache: fix refcount
> underflow in bcache_device_free()").
> 
> Maybe add a parameter to blk_cleanup_disk() or checking (disk->flags &
> GENHD_FL_UP) inside blk_cleanup_disk() ?

Please take a look at patch 4 in the series.