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Date: Tue, 28 Jul 2015 10:01:03 +0200
From: Michal Hocko <mhocko@kernel.org>
To: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Jonathan Corbet <corbet@lwn.net>, Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@kernel.org>,
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        linux-doc@vger.kernel.org, x86@kernel.org, kexec@lists.infradead.org,
        linux-kernel@vger.kernel.org, Ingo Molnar <mingo@redhat.com>,
        Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Subject: Re: [V2 PATCH 1/3] x86/panic: Fix re-entrance problem due to panic
 on NMI
Message-ID: <20150728080103.GD24972@dhcp22.suse.cz>
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On Tue 28-07-15 11:02:11, Hidehiro Kawai wrote:
[...]
> > Something like
> [...]
> > +void nmi_panic(const char *fmt, ...)
> 
> Since we can't directly pass variable arguments to a subroutine,

Sure, I was just too lazy to finish this as it was just an illustration
of the idea.

> we have to use a macro or do like this:
> 
> void nmi_panic(const char *msg)
> {
> ...
> 	panic("%s", msg);
> }
> 
> If there is no objection, I'm going to use a macro.

Your other patch needs panic_cpu externally visible so the macro should
be OK.
-- 
Michal Hocko
SUSE Labs