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Date: Mon, 10 Sep 2012 12:16:24 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Anton Vorontsov <anton.vorontsov@linaro.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
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Subject: Re: [PATCH 08/14] tty/serial/kgdboc: Add and wire up clear_irqs
 callback
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In-Reply-To: <20120910041357.GH29537@lizard>
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> serial port, the CPU receives NMI exception, and we fall into KDB shell.
> So, it is our "debug console", and it is able to interrupt (and thus
> debug) even IRQ handlers themselves.


You seem to have an assumption of single core here. What happens if the
NMI hits CPU #0 and the serial IRQ hits CPU #1 simultaneously ?

Alan