Date: Fri, 24 Jul 2015 17:07:12 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>, Willy Tarreau <w@1wt.eu>,
        Andy Lutomirski <luto@amacapital.net>, X86 ML <x86@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Borislav Petkov <bp@alien8.de>, Thomas Gleixner <tglx@linutronix.de>,
        Brian Gerst <brgerst@gmail.com>
Subject: Re: Dealing with the NMI mess
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On Fri, 24 Jul 2015 22:51:19 +0200
Peter Zijlstra <peterz@infradead.org> wrote:

 
> > Do we really take locks in the #DB handler?
> 
> do_debug()
>   send_sigtrap()
>     force_sig_info()
>       spin_lock_irqsave()
> 
> Now, I don't pretend to understand the condition before send_sigtrap(),
> so it _might_ be ok, but it sure as heck could do with a comment.

Or that force_sig_info() in send_sigtrap() looks like it can easily be
change to use an irq work queue.

-- Steve
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