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Subject: Re: kernel BUG at fs/buffer.c:LINE!
To:     jaegeuk@kernel.org
References: <0000000000009716290599fcd496@google.com>
Cc:     axboe@kernel.dk, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com,
        viro@zeniv.linux.org.uk
From:   Bart Van Assche <bvanassche@acm.org>
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Message-ID: <31033055-c245-4eda-2814-3fd8b0d59cb9@acm.org>
Date:   Wed, 18 Dec 2019 21:00:21 -0800
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Sender: linux-kernel-owner@vger.kernel.org
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On 2019-12-18 08:21, syzbot wrote:
> syzbot has bisected this bug to:
> 
> commit 5db470e229e22b7eda6e23b5566e532c96fb5bc3
> Author: Jaegeuk Kim <jaegeuk@kernel.org>
> Date:   Thu Jan 10 03:17:14 2019 +0000
> 
>     loop: drop caches if offset or block_size are changed
> 
> bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=13f3ca8ee00000
> start commit:   2187f215 Merge tag 'for-5.5-rc2-tag' of
> git://git.kernel.o..
> git tree:       upstream
> final crash:    https://syzkaller.appspot.com/x/report.txt?x=100bca8ee00000
> console output: https://syzkaller.appspot.com/x/log.txt?x=17f3ca8ee00000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=dcf10bf83926432a
> dashboard link:
> https://syzkaller.appspot.com/bug?extid=cfed5b56649bddf80d6e
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1171ba8ee00000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=107440aee00000

Hi Jaegeuk,

Since syzbot has identified a reproducer I think that it's easy to test
whether your new patch fixes what syzbot discovered. Have you already
had the chance to test this?

Thanks,

Bart.