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Date:   Mon, 9 Aug 2021 15:52:39 +0000
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Pavel Begunkov <asml.silence@gmail.com>
Cc:     linux-fsdevel@vger.kernel.org, Jens Axboe <axboe@kernel.dk>,
        io-uring@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/2] iter revert problems
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On Mon, Aug 09, 2021 at 12:52:35PM +0100, Pavel Begunkov wrote:
> For the bug description see 2/2. As mentioned there the current problems
> is because of generic_write_checks(), but there was also a similar case
> fixed in 5.12, which should have been triggerable by normal
> write(2)/read(2) and others.
> 
> It may be better to enforce reexpands as a long term solution, but for
> now this patchset is quickier and easier to backport.

	Umm...  Won't that screw the cases where we *are* doing proper
reexpands?  AFAICS, with your patches that flag doesn't go away once
it had been set...