From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>
Subject: Re: [PATCH 0/2][concept RFC] x86: BIOS-save kernel log to disk upon
	panic
Date: Wed, 26 Jan 2011 20:35:09 -0800
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To: Ingo Molnar <mingo-X9Un+BFzKDI@public.gmane.org>
Cc: Willy Tarreau <wtarreau-Dj75qbTlC0E76Z2rM5mHXA@public.gmane.org>, Dirk Hohndel <hohndel-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>, =?ISO-8859-1?Q?Fr=E9d=E9ric_W?= =?ISO-8859-1?Q?eisbecker?= <fweisbec-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, FBDEV-ML <linux-fbdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, IDE-ML <linux-ide-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Randy Dunlap <rdunlap-/UHa2rfvQTnk1uMJSBkQmQ@public.gmane.org>, James Bottomley <James.Bottomley-l3A5Bk7waGM@public.gmane.org>, X86-ML <x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, "Ahmed S. Darwish" <darwish.07-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Ingo Molnar <mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Jeff Garzik <jgarzik-e+AXbWqSrlAAvxtiuMwx3w@public.gmane.org>, Vivek Goyal <vgoyal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Peter Zijlstra <a.p.zijlstra-/NLkJaSkS4VmR6Xm/wNWPw@public.gmane.org>, Dirk.Hohndel-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, Borislav Petkov <bp-Gina5bIWoIWzQB+pC5nmwQ@public.gmane.org>, Dave Jones <davej-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Thomas Gleixner <tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org>, Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>, Arjan van de Ven <arjan-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>, Tony Luck <tony.luck-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>, KEXEC-ML <kexec-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org>, LKML <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Haren Myneni <hbabu-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>, Eric
List-Id: linux-ide@vger.kernel.org

On 01/26/2011 06:00 AM, Ingo Molnar wrote:
>
> I mean, use the warm reset vector to truly reset the box.
>
> Then, once a stable known-good kernel boots, *that* kernel can then recover all the
> log data which is sitting in a well-known place in RAM, automatically and
> transparently.
>
> Basically a bit like kexec, just more convenient and it also goes through the BIOS
> warm reset, so it might work better than kexec ...
>

The problem is that the BIOS will often wipe memory.

	-hpa