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Sender: Tejun Heo <htejun@gmail.com>
Date:   Thu, 20 May 2021 13:07:17 -0400
From:   Tejun Heo <tj@kernel.org>
To:     Dmitry Monakhov <dmtrmonakhov@yandex-team.ru>
Cc:     linux-kernel@vger.kernel.org, axboe@kernel.dk
Subject: Re: [PATCH] blk-throttle: fix race between submitter and throttler
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Hello, Dmitry.

On Thu, May 20, 2021 at 08:00:51PM +0300, Dmitry Monakhov wrote:
> >> + BUG_ON(!bio_flagged(parent, BIO_CHAIN));
> > 
> > Let's do WARN_ON_ONCE().
> If we hit this point when this mean that  ->bio_end_io  will be called for parent bio.
> Which likely result in use-after-free for that bio and silent data corruption for bio's pages
> So IMHO BUG_ON is more appropriate here. What do you think?

I see. That makes sense. Can you add a comment explaining the above?

Thanks.

-- 
tejun