Re: [PATCH 0/2] iter revert problems

From: Al Viro
Date: Mon Aug 09 2021 - 11:54:54 EST


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...