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Date: Tue, 7 Nov 2017 09:11:43 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Byungchul Park <byungchul.park@lge.com>
Cc: Dmitry Vyukov <dvyukov@google.com>, Al Viro <viro@zeniv.linux.org.uk>,
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Subject: Re: possible deadlock in generic_file_write_iter
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On Tue, Nov 07, 2017 at 09:54:42AM +0900, Byungchul Park wrote:
> > The best I could come up with is something like the below; its not
> > at all pretty and I could see people objecting; least of all myself for
> > the __complete() thing, but I ran out of creative naming juice.
> 
> Patches assigning a lock_class per gendisk were already applied in tip.
> I believe that solves this.
> 
>    e319e1fbd9d42420ab6eec0bfd75eb9ad7ca63b1
>    block, locking/lockdep: Assign a lock_class per gendisk used for
>    wait_for_completion()
> 
> I think the following proposal makes kernel too hacky.

Ah, I tough this was with those included...