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Date: Tue, 4 Nov 2025 13:03:09 +0100
From: Christoph Hellwig <hch@lst.de>
To: Damien Le Moal <dlemoal@kernel.org>
Cc: Chaitanya Kulkarni <chaitanyak@nvidia.com>,
	Bart Van Assche <bvanassche@acm.org>, Jens Axboe <axboe@kernel.dk>,
	"linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
	"linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>,
	Christoph Hellwig <hch@lst.de>,
	"dm-devel@lists.linux.dev" <dm-devel@lists.linux.dev>,
	Mike Snitzer <snitzer@kernel.org>,
	"Martin K . Petersen" <martin.petersen@oracle.com>,
	Mikulas Patocka <mpatocka@redhat.com>,
	"linux-xfs@vger.kernel.org" <linux-xfs@vger.kernel.org>,
	Carlos Maiolino <cem@kernel.org>,
	"linux-btrfs@vger.kernel.org" <linux-btrfs@vger.kernel.org>,
	David Sterba <dsterba@suse.com>,
	"linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
	Keith Busch <kbusch@kernel.org>
Subject: Re: [PATCH 07/13] block: track zone conditions
Message-ID: <20251104120309.GA16283@lst.de>
References: <20251031061307.185513-1-dlemoal@kernel.org> <20251031061307.185513-8-dlemoal@kernel.org> <40c87475-7d5a-4792-b2a6-3eeb8406f9be@acm.org> <93215b7c-80bd-4860-8a77-42cdd4db1ec6@kernel.org> <95c729d6-fd73-4480-af1c-68075b31cd1d@acm.org> <6008fbc8-b556-46d9-98a5-a4622731d206@nvidia.com> <83b60505-64a4-40fe-aa50-02a56ca7ad8c@kernel.org>
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On Tue, Nov 04, 2025 at 07:53:07AM +0900, Damien Le Moal wrote:
> > In case current file systems store this, isn't that a code duplication for each
> > fs ? perhaps having a central interface at block layer should help remove the
> > code duplication ?
> 
> catch 22: You cannot ask the file system without first knowing the zone layout
> and conditions of zone to check the file system metadata.

The file system also really needs to verify that it's view matches the
hardware view at mount time, otherwise you'll run into really nasty
cases later when they are out of sync due to a bug or corruption.