Subject: Re: [PATCH] block: loop: fix filesystem corruption in case of aio/dio
To: Ming Lei <ming.lei@canonical.com>, <linux-kernel@vger.kernel.org>
References: <1460717488-19796-1-git-send-email-ming.lei@canonical.com>
CC: <linux-block@vger.kernel.org>, Christoph Hellwig <hch@infradead.org>,
        Keith Busch <keith.busch@intel.com>, Al Viro <viro@zeniv.linux.org.uk>,
        "4.5" <stable@vger.kernel.org>
From: Jens Axboe <axboe@fb.com>
Message-ID: <5710F9E0.2050900@fb.com>
Date: Fri, 15 Apr 2016 08:25:36 -0600
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On 04/15/2016 04:51 AM, Ming Lei wrote:
> Starting from commit e36f620428(block: split bios to max possible length),
> block core starts to split bio in the middle of bvec.
>
> Unfortunately loop dio/aio doesn't consider this situation, and
> always treat 'iter.iov_offset' as zero. Then filesystem corruption
> is observed.
>
> This patch figures out the offset of the base bvevc via
> 'bio->bi_iter.bi_bvec_done' and fixes the issue by passing the offset
> to iov iterator.
>
> Fixes: e36f6204288088f (block: split bios to max possible length)
> Cc: Keith Busch <keith.busch@intel.com>
> Cc: Al Viro <viro@zeniv.linux.org.uk>
> Cc: stable@vger.kernel.org (4.5)
> Signed-off-by: Ming Lei <ming.lei@canonical.com>

Thanks Ming, queued up.

-- 
Jens Axboe