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Subject: Re: inconsistent lock state in xa_destroy
To:     syzbot <syzbot+cdcbdc0bd42e559b52b9@syzkaller.appspotmail.com>,
        io-uring@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com,
        viro@zeniv.linux.org.uk
References: <00000000000045ac4605b12a1720@google.com>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <de842e7f-fa50-193b-b1d7-c573e515ef8b@kernel.dk>
Date:   Thu, 8 Oct 2020 09:01:57 -0600
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On 10/8/20 9:00 AM, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    e4fb79c7 Add linux-next specific files for 20201008
> git tree:       linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=12555227900000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=568d41fe4341ed0f
> dashboard link: https://syzkaller.appspot.com/bug?extid=cdcbdc0bd42e559b52b9
> compiler:       gcc (GCC) 10.1.0-syz 20200507
> 
> Unfortunately, I don't have any reproducer for this issue yet.
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+cdcbdc0bd42e559b52b9@syzkaller.appspotmail.com

Already pushed out a fix for this, it's really an xarray issue where it just
assumes that destroy can irq grab the lock.

#syz fix: io_uring: no need to call xa_destroy() on empty xarray

-- 
Jens Axboe