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Date:   Tue, 24 May 2022 09:38:32 -0600
From:   Keith Busch <kbusch@kernel.org>
To:     Pankaj Raghav <pankydev8@gmail.com>
Cc:     Keith Busch <kbusch@fb.com>, linux-fsdevel@vger.kernel.org,
        linux-block@vger.kernel.org, axboe@kernel.dk,
        Kernel Team <Kernel-team@fb.com>, hch@lst.de,
        bvanassche@acm.org, damien.lemoal@opensource.wdc.com,
        ebiggers@kernel.org
Subject: Re: [PATCHv3 1/6] block/bio: remove duplicate append pages code
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On Tue, May 24, 2022 at 04:17:54PM +0200, Pankaj Raghav wrote:
> On Mon, May 23, 2022 at 02:01:14PM -0700, Keith Busch wrote:
> > -	if (WARN_ON_ONCE(!max_append_sectors))
> > -		return 0;
> I don't see this check in the append path. Should it be added in
> bio_iov_add_zone_append_page() function?

I'm not sure this check makes a lot of sense. If it just returns 0 here, then
won't that get bio_iov_iter_get_pages() stuck in an infinite loop? The bio
isn't filling, the iov isn't advancing, and 0 indicates keep-going.