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Subject: Re: RFC: SysRq nice-all-RT-tasks is broken
To: Steven Rostedt <rostedt@goodmis.org>
References: <be47a577-7dfe-a7b3-57e0-1f182edc568b@linux.vnet.ibm.com>
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Cc: Andrew Morton <akpm@osdl.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>
From: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Date: Wed, 8 Mar 2017 18:03:55 +0100
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On 08/03/2017 17:57, Steven Rostedt wrote:
> On Wed, 8 Mar 2017 11:51:14 -0500
> Steven Rostedt <rostedt@goodmis.org> wrote:
> 
> 
>> Hmm, that commit was added in 2.6.18, and you're right, a lot has
>> changed since then. Have you tried removing it and running it under
>> lockdep, and see if it triggers any warnings?
> 
> I did a little digging, and it appears that its the rt mutex wait lock
> that the comment was referring to. Today that spin lock is irq safe. I
> believe its safe to remove the BUG_ON(). Want me to send a patch?

Sure, go ahead ;)

Thanks,
Laurent.