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	id 2F58368B05; Fri, 24 May 2024 09:39:57 +0200 (CEST)
Date: Fri, 24 May 2024 09:39:57 +0200
From: Christoph Hellwig <hch@lst.de>
To: Hannes Reinecke <hare@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>, Christoph Hellwig <hch@lst.de>,
	Mike Snitzer <snitzer@kernel.org>, linux-block@vger.kernel.org,
	dm-devel@lists.linux.dev
Subject: Re: [PATCH] block: blk_set_stacking_limits() doesn't validate
Message-ID: <20240524073957.GB16336@lst.de>
References: <20240524062119.143788-1-hare@kernel.org>
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On Fri, May 24, 2024 at 08:21:19AM +0200, Hannes Reinecke wrote:
> blk_validate_zoned_limits() checks whether any of the zoned limits
> are set for non-zoned limits. As blk_set_stacking_limits() sets
> max_zone_append_sectors() it'll fail to validate.

Except that you now broke it for zone devices.  Normally if we are
not building a stacked zoned device there should at least be one
underlying device that has a zero max_zone_append_limit, thus lowering
the stacked device limit to 0.  I guess you have a scenario where that
is not the case, so please explain it so that we can fix it.