From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Subject: Re: INFO: rcu detected stall in vprintk_emit
Date: Tue, 26 Jun 2018 14:07:31 +0900
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Cc: Steven Rostedt <rostedt@goodmis.org>,
        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        syzbot <syzbot+d29d18215e477cfbfbdd@syzkaller.appspotmail.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Petr Mladek <pmladek@suse.com>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        syzkaller-bugs <syzkaller-bugs@googlegroups.com>,
        Samuel Ortiz <sameo@linux.intel.com>,
        "David S. Miller" <davem@davemloft.net>,
        linux-wireless@vger.kernel.org, netdev <netdev@vger.kernel.org>
To: Dmitry Vyukov <dvyukov@google.com>
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On (06/26/18 07:03), Dmitry Vyukov wrote:
> > I don't think this is a printk() issue per se, so I think Option B is
> > the only option. You should not get stuck in an infinite loop if we run
> > short on memory. Perhaps we could have an Option C which would exit
> > this loop gracefully with some kind of error. But I haven't looked at
> > the surrounding code to be sure if that is possible.
> 
> I suspect this is not even OOM.

Could be. But at the same time it stalls RCU, so OOM at some point
becomes realistic.

	-ss