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Date: Mon, 24 May 2021 09:29:50 +0200
From: Christoph Hellwig <hch@lst.de>
To: Hannes Reinecke <hare@suse.de>
Cc: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
	Geert Uytterhoeven <geert@linux-m68k.org>,
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	Mike Snitzer <snitzer@redhat.com>, Song Liu <song@kernel.org>,
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Subject: Re: [PATCH 18/26] nvme-multipath: convert to
 blk_alloc_disk/blk_cleanup_disk
Message-ID: <20210524072950.GG23890@lst.de>
References: <20210521055116.1053587-1-hch@lst.de> <20210521055116.1053587-19-hch@lst.de> <1a771bf9-5083-c440-f0e1-5f6920b5b017@suse.de>
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On Sun, May 23, 2021 at 10:20:27AM +0200, Hannes Reinecke wrote:
> What about the check for GENHD_FL_UP a bit further up in line 766?
> Can this still happen with the new allocation scheme, ie is there still a 
> difference in lifetime between ->disk and ->disk->queue?

Yes, nvme_free_ns_head can still be called before device_add_disk was
called for an allocated nshead gendisk during error handling of the
setup path.  There is still a difference in the lifetime in that they
are separately refcounted, but it does not matter to the driver.