Re: BUG: workqueue lockup (4)

From: Dmitry Vyukov <dvyukov@google.com>
To: syzbot <syzbot+08116743f8ad6f9a6de7@syzkaller.appspotmail.com>,
	a.zummo@towertech.it, alexandre.belloni@bootlin.com,
	linux-rtc@vger.kernel.org
Cc: LKML <linux-kernel@vger.kernel.org>,
	syzkaller-bugs <syzkaller-bugs@googlegroups.com>
Subject: Re: BUG: workqueue lockup (4)
Date: Sun, 7 Oct 2018 14:18:31 +0200	[thread overview]
Message-ID: <CACT4Y+ZAoLro6LHhaA2EuWF1nAWAA=NAVtpMammhspL4V2aMgw@mail.gmail.com> (raw)
In-Reply-To: <0000000000005764090577a27486@google.com>

On Sun, Oct 7, 2018 at 2:15 PM, syzbot
<syzbot+08116743f8ad6f9a6de7@syzkaller.appspotmail.com> wrote:
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit:    c1d84a1b42ef Merge git://git.kernel.org/pub/scm/linux/kern..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=14c5f491400000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=c0af03fe452b65fb
> dashboard link: https://syzkaller.appspot.com/bug?extid=08116743f8ad6f9a6de7
> compiler:       gcc (GCC) 8.0.1 20180413 (experimental)
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14514a6e400000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1025ebb9400000

The reproducer seems to be all about rtc. So +rtc maintainers.

> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+08116743f8ad6f9a6de7@syzkaller.appspotmail.com
>
> BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=0 stuck for 204s!
> Showing busy workqueues and worker pools:
> workqueue events: flags=0x0
>   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=4/256
>     in-flight: 14:rtc_timer_do_work
>     pending: vmstat_shepherd, cache_reap, check_corruption
> workqueue events_power_efficient: flags=0x80
>   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256
>     pending: do_cache_clean
> workqueue mm_percpu_wq: flags=0x8
>   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256
>     pending: vmstat_update
> workqueue kacpi_notify: flags=0x0
>   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/1
>     pending: acpi_os_execute_deferred
> pool 0: cpus=0 node=0 flags=0x0 nice=0 hung=204s workers=2 idle: 2683
>
>
> ---
> This bug is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@googlegroups.com.
>
> syzbot will keep track of this bug report. See:
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> syzbot can test patches for this bug, for details see:
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>
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