From mboxrd@z Thu Jan  1 00:00:00 1970
From: Horms <horms@verge.net.au>
Subject: Re: [Patch] Enable "sysrq c" handler for domU coredump
Date: Tue, 1 Aug 2006 15:48:06 +0900
Message-ID: <20060801064805.GA14886@verge.net.au>
References: <20060801034824.GD13414@verge.net.au>
	<4FC6B524762864takebe_akio@jp.fujitsu.com>
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To: Akio Takebe <takebe_akio@jp.fujitsu.com>
Cc: xen-devel <xen-devel@lists.xensource.com>, Kouya Shimura <kouya@jp.fujitsu.com>
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On Tue, Aug 01, 2006 at 01:39:23PM +0900, Akio Takebe wrote:
> Hi, Horms
> 
> >
> >That seems fine to me. Though there was some resistance to a
> >patch I sent which adds a panic option to xen-console, which
> >is the hypervisor equivalent of sysrq.
> >
> This patch focus only manually dumping domU's core.
> How can I use the panic option of xen-console?
> I thought your patch to panic xen.
> Can I dump domU's core with the option?

Sorry, I was not clear.

Yes, my patch is to panic (or more recently cause a crash dump) 
in the hypervisor. It does not give any special behaviour to
the domains.

What I meant was, that the idea of adding a panic to domU's sysrq
is similar to my idea of adding panic to the xen console. And I was
asked to change this patch to make it trigger a kdump directly,
rather than a panic.

I think that your sysrq patch and my xen-console panic patches
are related, and I wanted to bring that into the discussion.

> >Also, is this option really Xen specific. It seems it
> >might be just as useful in regular Linux.
>
> This is a patch to dump domU's core,
> so Linux is not useful becaus Linux can dump by calling crash_kexec().

Right, but it does this using panic() which does have some effect
in regular Linux. I am just wondering if your solution answers
a more generic question than how to dump domU.

-- 
Horms
  H: http://www.vergenet.net/~horms/
  W: http://www.valinux.co.jp/en/