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Subject: Re: [PATCH v2] loop: avoid EAGAIN, if offset or block_size are
 changed
To:     Jaegeuk Kim <jaegeuk@kernel.org>, linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net
Cc:     stable@vger.kernel.org, Jens Axboe <axboe@kernel.dk>,
        linux-block@vger.kernel.org
References: <20190518004751.18962-1-jaegeuk@kernel.org>
 <20190518005304.GA19446@jaegeuk-macbookpro.roam.corp.google.com>
From:   Bart Van Assche <bvanassche@acm.org>
Message-ID: <1e1aae74-bd6b-dddb-0c88-660aac33872c@acm.org>
Date:   Tue, 19 Nov 2019 15:40:55 -0800
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On 5/17/19 5:53 PM, Jaegeuk Kim wrote:
> This patch tries to avoid EAGAIN due to nrpages!=0 that was originally trying
> to drop stale pages resulting in wrong data access.
> 
> Report: https://bugs.chromium.org/p/chromium/issues/detail?id=938958#c38

Please provide a more detailed commit description. What is wrong with 
the current implementation and why is the new behavior considered the 
correct behavior?

This patch moves draining code from before the following comment to 
after that comment:

/* I/O need to be drained during transfer transition */

Is that comment still correct or should it perhaps be updated?

Thanks,

Bart.