Re: INFO: rcu detected stall in sys_creat

Tetsuo Handa
2019-01-20T01:52:43Z

On 2019/01/20 4:00, Dmitry Vyukov wrote:
> "On Sun, Oct 21, 2018 at 7:15 PM syzbot
> <syzbot+3155335ece2c94bead44@syzkaller.appspotmail.com> wrote:
>>
>> Hello,
>>
>> syzbot found the following crash on:
>>
>> HEAD commit: 8c60c36d0b8c Add linux-next specific files for 20181019
>> git tree: linux-next
>> console output: https://syzkaller.appspot.com/x/log.txt?x=160c9245400000
>> kernel config: https://syzkaller.appspot.com/x/.config?x=8b6d7c4c81535e89
>> dashboard link: https://syzkaller.appspot.com/bug?extid=3155335ece2c94bead44
>> compiler: gcc (GCC) 8.0.1 20180413 (experimental)
>>
>> Unfortunately, I don't have any reproducer for this crash yet.
>
> +Tetsuo, Jan, Jens
>
> This is a stall, but it involves __getblk_gfp. Is it the same bug as
> "INFO: task hung in generic_file_write_iter":
> https://syzkaller.appspot.com/bug?id=8afdd02539e35fc02ac7699014bc54a87fdd8dc0
> which will be fixed with "blockdev: Fix livelocks on loop device".
>
> This bug also has 10 other duplicates:
> https://syzkaller.appspot.com/bug?extid=3155335ece2c94bead44

Yes, I think so.

#syz dup: INFO: task hung in generic_file_write_iter