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Date: Tue, 14 Feb 2017 19:29:56 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Tony Lindgren <tony@atomide.com>, Petr Mladek <pmladek@suse.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Thomas Gleixner <tglx@linutronix.de>, linux-kernel@vger.kernel.org,
        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>, linux-pm@vger.kernel.org,
        John Stultz <john.stultz@linaro.org>
Subject: Re: Regression in next with use printk_safe buffers in printk
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On Wed, Feb 15, 2017 at 01:56:45AM +0900, Sergey Senozhatsky wrote:
> that crossed my mind, but I kinda assumed that we do printk() from
> under tk_core using sched fair, and rt_runtime_lock is from sched rt.

That's all true; lockdep doesn't care :-) All it knows is that at some
point those locks nest.