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Date:   Mon, 31 Jul 2023 18:01:14 +0800
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Subject: Re: [syzbot] [btrfs?] kernel BUG in prepare_to_merge
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To:     Christoph Hellwig <hch@infradead.org>
Cc:     Christoph Hellwig <hch@lst.de>,
        syzbot <syzbot+ae97a827ae1c3336bbb4@syzkaller.appspotmail.com>,
        clm@fb.com, dsterba@suse.com, johannes.thumshirn@wdc.com,
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        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        syzkaller-bugs@googlegroups.com
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From:   Qu Wenruo <quwenruo.btrfs@gmx.com>
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On 2023/7/31 17:46, Christoph Hellwig wrote:
> Thanks.  I've not been able to reproduce it on the apparent bisection
> commit for more than half an hour, but running it on the originally
> reported commit reproduces it after a few minutes.  I'll see if I
> can come up with a better bisection.
>

I checked the related code, and didn't find anything obvious.

But there is a chance that the image is intentionally corrupted so that
we got a reloc root but incorrect root owner.

Thus I sent out a patch to make that triggering ASSERT() to a more
graceful exit:

https://lore.kernel.org/linux-btrfs/24881cc9caf738f6248232709d7357d3186773=
b5.1690782754.git.wqu@suse.com/T/#u

Although I never got the C reproducer to trigger, thus no confirmation
on that.

Thanks,
Qu