From: Jens Axboe <axboe@kernel.dk>
To: Eric Biggers <ebiggers3@gmail.com>,
syzbot
<bot+583353673e394aa41e5fb68ddc8b8d9d5c8d576f@syzkaller.appspotmail.com>
Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
mingo@redhat.com, rostedt@goodmis.org,
syzkaller-bugs@googlegroups.com
Subject: Re: possible deadlock in blk_trace_remove
Date: Sun, 3 Dec 2017 17:24:32 -0700 [thread overview]
Message-ID: <9f7ab661-7d57-3e84-769c-6d103557f342@kernel.dk> (raw)
In-Reply-To: <20171203202434.GD844@zzz.localdomain>
On 12/03/2017 01:24 PM, Eric Biggers wrote:
> On Sun, Nov 19, 2017 at 02:36:01AM -0800, syzbot wrote:
>> Hello,
>>
>> syzkaller hit the following crash on
>> d9e0e63d9a6f88440eb201e1491fcf730272c706
>> git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/master
>> compiler: gcc (GCC) 7.1.1 20170620
>> .config is attached
>> Raw console output is attached.
>>
>> Unfortunately, I don't have any reproducer for this bug yet.
>>
>>
>> Use struct sctp_sack_info instead
>>
>> ============================================
>> WARNING: possible recursive locking detected
>> 4.14.0-rc8-next-20171110+ #40 Not tainted
>> --------------------------------------------
>> syz-executor6/21462 is trying to acquire lock:
>> (&q->blk_trace_mutex){+.+.}, at: [<ffffffff81760261>]
>> blk_trace_remove+0x21/0x40 kernel/trace/blktrace.c:373
>>
>> but task is already holding lock:
>> (&q->blk_trace_mutex){+.+.}, at: [<ffffffff81763b38>]
>> blk_trace_setup+0x38/0x70 kernel/trace/blktrace.c:606
>>
>> other info that might help us debug this:
>> Possible unsafe locking scenario:
>
> #syz fix: blktrace: fix trace mutex deadlock
This is fixed in current -git.
--
Jens Axboe
next prev parent reply other threads:[~2017-12-04 0:24 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <001a1141f8dc4440a9055e53896e@google.com>
2017-11-19 18:50 ` possible deadlock in blk_trace_remove Jens Axboe
2017-12-03 20:24 ` Eric Biggers
2017-12-04 0:24 ` Jens Axboe [this message]
2017-12-04 0:44 ` Eric Biggers
2017-12-04 0:47 ` Jens Axboe
2017-12-04 3:47 ` Mike Galbraith
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