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Date: Thu, 28 Sep 2017 21:15:21 +0900
From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: "Levin, Alexander (Sasha Levin)" <alexander.levin@verizon.com>,
        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Sasha Levin <levinsasha928@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>,
        "linux-kernel@vger.kernel.org List" <linux-kernel@vger.kernel.org>,
        "pmladek@suse.com" <pmladek@suse.com>,
        "sergey.senozhatsky@gmail.com" <sergey.senozhatsky@gmail.com>,
        "rostedt@goodmis.org" <rostedt@goodmis.org>
Subject: Re: sched: serial port lockdep warning when offlining CPUs
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On (09/28/17 14:07), Peter Zijlstra wrote:
[..]
> > Nah.. WARN's _should_ not trigger. If they do we fix that.
> > 
> > Getting a lockdep splat after a WARN is something I can live with.
> > 
> > And you really don't want that deferred nonsense for WARNs, because that
> > means you'll risk not over getting the output.
> 
> Note that I'm not likely to care too much either way, because I'm simply
> not using any of that printk() nonsense ;-)
> 
> 
> I'll repost my patches now; otherwise I'll forget again anyway.

#define printk printk_deferred

should also do the trick and... make the kernel great again!  :)

	-ss