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Subject: Re: [RFC/Requirements/Design] h/w error reporting
From: Steven Rostedt <rostedt@goodmis.org>
To: Ingo Molnar <mingo@elte.hu>
Cc: Borislav Petkov <bp@alien8.de>, Peter Zijlstra <a.p.zijlstra@chello.nl>,
        "Luck, Tony" <tony.luck@intel.com>, linux-kernel@vger.kernel.org,
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        =?ISO-8859-1?Q?Fr=E9d=E9ric?= Weisbecker <fweisbec@gmail.com>,
        Arnaldo Carvalho de Melo <acme@redhat.com>,
        Arjan van de Ven <arjan@infradead.org>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
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Date: Wed, 10 Nov 2010 13:09:47 -0500
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On Wed, 2010-11-10 at 18:41 +0100, Ingo Molnar wrote:

> > It would also be cool to be able to allocate those buffers as early as possible, 
> > even if before MCA is enabled, so that I won't have to copy MCE data which got 
> > logged before the tracing subsystem got enabled to the buffers proper.
> 
> We could even have some (small) statically enabled build-time buffer that could be 
> enabled straight away before any allocators are enabled.

I'm not sure it needs to be small. We can have a persistent buffer that
may be resized at any time. It can start off small, or with a kernel
command line, be as big as you want it.

Basically, what ftrace has now.

Also, with a way that root user can get a handle on this buffer, and
just trace global events with it.

-- Steve