* Re: [syzbot] WARNING in io_wqe_enqueue
[not found] <0000000000006e1be105c3ed13fe@google.com>
@ 2021-06-04 20:22 ` syzbot
2021-06-08 9:47 ` Hao Xu
0 siblings, 1 reply; 4+ messages in thread
From: syzbot @ 2021-06-04 20:22 UTC (permalink / raw)
To: asml.silence, axboe, io-uring, linux-fsdevel, linux-kernel,
syzkaller-bugs, viro
syzbot has bisected this issue to:
commit 24369c2e3bb06d8c4e71fd6ceaf4f8a01ae79b7c
Author: Pavel Begunkov <asml.silence@gmail.com>
Date: Tue Jan 28 00:15:48 2020 +0000
io_uring: add io-wq workqueue sharing
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=17934777d00000
start commit: f88cd3fb Merge tag 'vfio-v5.13-rc5' of git://github.com/aw..
git tree: upstream
final oops: https://syzkaller.appspot.com/x/report.txt?x=14534777d00000
console output: https://syzkaller.appspot.com/x/log.txt?x=10534777d00000
kernel config: https://syzkaller.appspot.com/x/.config?x=82d85e75046e5e64
dashboard link: https://syzkaller.appspot.com/bug?extid=ea2f1484cffe5109dc10
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16d5772fd00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10525947d00000
Reported-by: syzbot+ea2f1484cffe5109dc10@syzkaller.appspotmail.com
Fixes: 24369c2e3bb0 ("io_uring: add io-wq workqueue sharing")
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [syzbot] WARNING in io_wqe_enqueue
2021-06-04 20:22 ` [syzbot] WARNING in io_wqe_enqueue syzbot
@ 2021-06-08 9:47 ` Hao Xu
2021-06-08 12:01 ` Dmitry Vyukov
0 siblings, 1 reply; 4+ messages in thread
From: Hao Xu @ 2021-06-08 9:47 UTC (permalink / raw)
To: syzbot, asml.silence, axboe, io-uring, linux-fsdevel,
linux-kernel, syzkaller-bugs, viro
在 2021/6/5 上午4:22, syzbot 写道:
> syzbot has bisected this issue to:
>
> commit 24369c2e3bb06d8c4e71fd6ceaf4f8a01ae79b7c
> Author: Pavel Begunkov <asml.silence@gmail.com>
> Date: Tue Jan 28 00:15:48 2020 +0000
>
> io_uring: add io-wq workqueue sharing
>
> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=17934777d00000
> start commit: f88cd3fb Merge tag 'vfio-v5.13-rc5' of git://github.com/aw..
> git tree: upstream
> final oops: https://syzkaller.appspot.com/x/report.txt?x=14534777d00000
> console output: https://syzkaller.appspot.com/x/log.txt?x=10534777d00000
> kernel config: https://syzkaller.appspot.com/x/.config?x=82d85e75046e5e64
> dashboard link: https://syzkaller.appspot.com/bug?extid=ea2f1484cffe5109dc10
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16d5772fd00000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10525947d00000
>
> Reported-by: syzbot+ea2f1484cffe5109dc10@syzkaller.appspotmail.com
> Fixes: 24369c2e3bb0 ("io_uring: add io-wq workqueue sharing")
>
> For information about bisection process see: https://goo.gl/tpsmEJ#bisection
>
This is not a bug, the repro program first set RLIMIT_NPROC to 0, then
submits an unbound work whcih raises a warning of
WARN_ON_ONCE(!acct->max_workers). Since unbound->max_workers is
task_rlimit(current, RLIMIT_NPROC), so it is expected.
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [syzbot] WARNING in io_wqe_enqueue
2021-06-08 9:47 ` Hao Xu
@ 2021-06-08 12:01 ` Dmitry Vyukov
2021-06-10 3:03 ` Hao Xu
0 siblings, 1 reply; 4+ messages in thread
From: Dmitry Vyukov @ 2021-06-08 12:01 UTC (permalink / raw)
To: Hao Xu
Cc: syzbot, Pavel Begunkov, Jens Axboe, io-uring, linux-fsdevel, LKML,
syzkaller-bugs, Al Viro
On Tue, Jun 8, 2021 at 11:47 AM Hao Xu <haoxu@linux.alibaba.com> wrote:
>
> 在 2021/6/5 上午4:22, syzbot 写道:
> > syzbot has bisected this issue to:
> >
> > commit 24369c2e3bb06d8c4e71fd6ceaf4f8a01ae79b7c
> > Author: Pavel Begunkov <asml.silence@gmail.com>
> > Date: Tue Jan 28 00:15:48 2020 +0000
> >
> > io_uring: add io-wq workqueue sharing
> >
> > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=17934777d00000
> > start commit: f88cd3fb Merge tag 'vfio-v5.13-rc5' of git://github.com/aw..
> > git tree: upstream
> > final oops: https://syzkaller.appspot.com/x/report.txt?x=14534777d00000
> > console output: https://syzkaller.appspot.com/x/log.txt?x=10534777d00000
> > kernel config: https://syzkaller.appspot.com/x/.config?x=82d85e75046e5e64
> > dashboard link: https://syzkaller.appspot.com/bug?extid=ea2f1484cffe5109dc10
> > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16d5772fd00000
> > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10525947d00000
> >
> > Reported-by: syzbot+ea2f1484cffe5109dc10@syzkaller.appspotmail.com
> > Fixes: 24369c2e3bb0 ("io_uring: add io-wq workqueue sharing")
> >
> > For information about bisection process see: https://goo.gl/tpsmEJ#bisection
> >
> This is not a bug, the repro program first set RLIMIT_NPROC to 0, then
> submits an unbound work whcih raises a warning of
> WARN_ON_ONCE(!acct->max_workers). Since unbound->max_workers is
> task_rlimit(current, RLIMIT_NPROC), so it is expected.
Hi Hao,
Then this is a mis-use of WARN_ON. If this check is intended for end
users, it needs to use pr_err (also print understandable message and
no stack trace which is most likely not useful for end users):
https://elixir.bootlin.com/linux/v5.13-rc5/source/include/asm-generic/bug.h#L71
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [syzbot] WARNING in io_wqe_enqueue
2021-06-08 12:01 ` Dmitry Vyukov
@ 2021-06-10 3:03 ` Hao Xu
0 siblings, 0 replies; 4+ messages in thread
From: Hao Xu @ 2021-06-10 3:03 UTC (permalink / raw)
To: Dmitry Vyukov
Cc: syzbot, Pavel Begunkov, Jens Axboe, io-uring, linux-fsdevel, LKML,
syzkaller-bugs, Al Viro
在 2021/6/8 下午8:01, Dmitry Vyukov 写道:
> On Tue, Jun 8, 2021 at 11:47 AM Hao Xu <haoxu@linux.alibaba.com> wrote:
>>
>> 在 2021/6/5 上午4:22, syzbot 写道:
>>> syzbot has bisected this issue to:
>>>
>>> commit 24369c2e3bb06d8c4e71fd6ceaf4f8a01ae79b7c
>>> Author: Pavel Begunkov <asml.silence@gmail.com>
>>> Date: Tue Jan 28 00:15:48 2020 +0000
>>>
>>> io_uring: add io-wq workqueue sharing
>>>
>>> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=17934777d00000
>>> start commit: f88cd3fb Merge tag 'vfio-v5.13-rc5' of git://github.com/aw..
>>> git tree: upstream
>>> final oops: https://syzkaller.appspot.com/x/report.txt?x=14534777d00000
>>> console output: https://syzkaller.appspot.com/x/log.txt?x=10534777d00000
>>> kernel config: https://syzkaller.appspot.com/x/.config?x=82d85e75046e5e64
>>> dashboard link: https://syzkaller.appspot.com/bug?extid=ea2f1484cffe5109dc10
>>> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16d5772fd00000
>>> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10525947d00000
>>>
>>> Reported-by: syzbot+ea2f1484cffe5109dc10@syzkaller.appspotmail.com
>>> Fixes: 24369c2e3bb0 ("io_uring: add io-wq workqueue sharing")
>>>
>>> For information about bisection process see: https://goo.gl/tpsmEJ#bisection
>>>
>> This is not a bug, the repro program first set RLIMIT_NPROC to 0, then
>> submits an unbound work whcih raises a warning of
>> WARN_ON_ONCE(!acct->max_workers). Since unbound->max_workers is
>> task_rlimit(current, RLIMIT_NPROC), so it is expected.
>
> Hi Hao,
>
> Then this is a mis-use of WARN_ON. If this check is intended for end
> users, it needs to use pr_err (also print understandable message and
> no stack trace which is most likely not useful for end users):
> https://elixir.bootlin.com/linux/v5.13-rc5/source/include/asm-generic/bug.h#L71
>
Agree, pr_err/pr_warn is better here.
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2021-06-10 3:04 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
[not found] <0000000000006e1be105c3ed13fe@google.com>
2021-06-04 20:22 ` [syzbot] WARNING in io_wqe_enqueue syzbot
2021-06-08 9:47 ` Hao Xu
2021-06-08 12:01 ` Dmitry Vyukov
2021-06-10 3:03 ` Hao Xu
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).