From mboxrd@z Thu Jan  1 00:00:00 1970
From: Olaf Hering <olaf@aepfle.de>
Subject: Re: xenstore index reset in xb_init_comms breaks domU
	kdump
Date: Wed, 26 Jan 2011 15:30:47 +0100
Message-ID: <20110126143047.GA29825@aepfle.de>
References: <20110126140043.GA27631@aepfle.de>
 <C965DE5E.127A2%keir@xen.org>
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To: Keir Fraser <keir@xen.org>
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On Wed, Jan 26, Keir Fraser wrote:

> I think it is needed for save/restore. It may not be needed during boot
> though. Your safest (lowest impact) fix would be to skip the reset when
> booting a crash kernel. A kernel knows it is a crash kernel, I believe?

There is is is_kdump_kernel(), which relies on an unexported variable.
However, the kdump tool in SLES11 passes 'reset_devices' in cmdline. And
this variable is exported and used in a few drivers to do extra hardware
reset. My patch adds a if (!reset_devices) before the assignment.

reset_devices was added in commit
7e96287ddc4f42081e18248b6167041c0908004c and appeared in 2.6.19. Its not
yet part of linux-2.6.18-xen.hg, it should be easy to backport.

I will post my SLES11 SP1 version of the kdump patch shortly.

Olaf