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Subject: Re: [syzbot] WARNING: ODEBUG bug in __put_task_struct
To:     syzbot <syzbot+30a60157d4ef222fd5e2@syzkaller.appspotmail.com>,
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References: <000000000000bb843a05cfa99111@google.com>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <bd03422b-4a19-c518-f550-13cd7be243fc@kernel.dk>
Date:   Sun, 31 Oct 2021 13:41:04 -0600
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On 10/31/21 11:41 AM, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    bdcc9f6a5682 Add linux-next specific files for 20211029
> git tree:       linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=1413226ab00000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=cea91ee10b0cd274
> dashboard link: https://syzkaller.appspot.com/bug?extid=30a60157d4ef222fd5e2
> compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=121ba3e2b00000
> 
> The issue was bisected to:
> 
> commit 34ced75ca1f63fac6148497971212583aa0f7a87
> Author: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
> Date:   Mon Oct 25 05:38:48 2021 +0000
> 
>     io_uring: reduce frequent add_wait_queue() overhead for multi-shot poll request

This was dropped from the tree last week:

#syz invalid

-- 
Jens Axboe