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Date:   Thu, 14 Aug 2014 16:45:35 +0200
From:   Ralf Baechle <ralf@linux-mips.org>
To:     Sergey Ryazanov <ryazanov.s.a@gmail.com>
Cc:     Linux MIPS <linux-mips@linux-mips.org>
Subject: Re: [PATCH 1/2] MIPS: MSP71xx: remove unused plat_irq_dispatch()
 argument
Message-ID: <20140814144535.GG21008@linux-mips.org>
References: <1407967776-7320-1-git-send-email-ryazanov.s.a@gmail.com>
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 <20140814124652.GE21008@linux-mips.org>
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On Thu, Aug 14, 2014 at 06:39:17PM +0400, Sergey Ryazanov wrote:

> >> Remove unused argument to make the plat_irq_dispatch() function
> >> declaration similar to the realization of other platforms.
> >
> > The issue may be harmless but the regs argument of the false argument
> > isn't even being passed in!
> >
> IMHO, this argument can't cause smth terrible, until nobody tries to
> access it, but I can mistake.

Correct.

In this particular case it appears that the value passed for regs is
whatever value there was in $a0 in the interrupted code.  Dereferencing
that kind of value would most likely be lethal and crash the kernel
during bootup.

  Ralf