From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
To: Hillf Danton <hdanton@sina.com>,
syzbot <syzbot+2e39bc6569d281acbcfb@syzkaller.appspotmail.com>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
Will Deacon <will@kernel.org>, Waiman Long <longman@redhat.com>,
Boqun Feng <boqun.feng@gmail.com>,
Dmitry Vyukov <dvyukov@google.com>,
linux-kernel@vger.kernel.org, linux-mm@kvack.org,
syzkaller-bugs@googlegroups.com
Subject: Re: [syzbot] INFO: task hung in rfkill_global_led_trigger_worker (2)
Date: Wed, 16 Nov 2022 18:27:45 +0900 [thread overview]
Message-ID: <8a3964bd-41fa-5179-1916-565decd11f50@I-love.SAKURA.ne.jp> (raw)
In-Reply-To: <20221116041716.2797-1-hdanton@sina.com>
On 2022/11/16 13:17, Hillf Danton wrote:
> No deadlock was reported for syz-executor145/4505 and syz-executor145/4516.
> Why?
Lockdep should be able to report this real deadlock case. But unfortunately,
>> INFO: task syz-executor145:4505 blocked for more than 143 seconds.
>> Not tainted 6.1.0-rc5-syzkaller-00008-ge01d50cbd6ee #0
>> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
>> task:syz-executor145 state:D stack:21896 pid:4505 ppid:3645 flags:0x00004002
>>
>> 2 locks held by syz-executor145/4505:
>> #0: ffff88807268e100 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline]
>> #0: ffff88807268e100 (&dev->mutex){....}-{3:3}, at: nfc_unregister_device+0x87/0x290 net/nfc/core.c:1165
>> #1: ffffffff8e787b08 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_unregister+0xcb/0x220 net/rfkill/core.c:1130
>>
>> INFO: task syz-executor145:4516 blocked for more than 144 seconds.
>> Not tainted 6.1.0-rc5-syzkaller-00008-ge01d50cbd6ee #0
>> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
>> task:syz-executor145 state:D stack:23096 pid:4516 ppid:3647 flags:0x00004004
>>
>> 2 locks held by syz-executor145/4516:
>> #0: ffffffff8e787b08 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_fop_write+0x1b3/0x790 net/rfkill/core.c:1278
>> #1: ffff88807268e100 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline]
>> #1: ffff88807268e100 (&dev->mutex){....}-{3:3}, at: nfc_dev_down+0x33/0x260 net/nfc/core.c:143
device_initialize() hides dev->mutex from lockdep tests; explained at
https://groups.google.com/g/syzkaller-bugs/c/Uj9LqEUCwac/m/BhdTjWhNAQAJ .
parent reply other threads:[~2022-11-16 9:28 UTC|newest]
Thread overview: expand[flat|nested] mbox.gz Atom feed
[parent not found: <20221116041716.2797-1-hdanton@sina.com>]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=8a3964bd-41fa-5179-1916-565decd11f50@I-love.SAKURA.ne.jp \
--to=penguin-kernel@i-love.sakura.ne.jp \
--cc=boqun.feng@gmail.com \
--cc=dvyukov@google.com \
--cc=gregkh@linuxfoundation.org \
--cc=hdanton@sina.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=longman@redhat.com \
--cc=peterz@infradead.org \
--cc=syzbot+2e39bc6569d281acbcfb@syzkaller.appspotmail.com \
--cc=syzkaller-bugs@googlegroups.com \
--cc=will@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox