From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760727AbXH3OXP (ORCPT ); Thu, 30 Aug 2007 10:23:15 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757036AbXH3OXB (ORCPT ); Thu, 30 Aug 2007 10:23:01 -0400 Received: from lisa.in-ulm.de ([217.10.8.8]:56079 "HELO mail.in-ulm.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with SMTP id S1756461AbXH3OXA (ORCPT ); Thu, 30 Aug 2007 10:23:00 -0400 X-Greylist: delayed 402 seconds by postgrey-1.27 at vger.kernel.org; Thu, 30 Aug 2007 10:23:00 EDT Date: Thu, 30 Aug 2007 16:15:28 +0200 From: Christian Ehrhardt To: linux-kernel@vger.kernel.org, hpa@zytor.com Subject: New x886-Setup code breaks HVM-XEN boot Message-ID: <20070830141528.GA307@lisa.in-ulm.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi, I am trying to boot a current 2.6 kernel as a guest under XEN in HVM mode. With linux-2.6.22.(5) as the guest this works fine but current git kernels fail very early in the boot process. The XEN host is a debian kernel with XEN enabled (2.6.18-4-xen-686). The XEN guest is a vanilla kernel from kernel org booting with LILO 22.6.1 in HVM mode. I bisected the problem and the bisection points at this commit: | # bad: [4fd06960f120e02e9abc802a09f9511c400042a5] Use the new x86 setup code for i386 | git-bisect bad 4fd06960f120e02e9abc802a09f9511c400042a5 The boot of a current git snapshot fails as follows: bash$ sudo xm console guest LILO 22.6.1 boot: lkcur Loading lkcur......................... BIOS data check bypassed bash$ Note the the xm console command terminates on its own, i.e. the guest machine seems to halt and not hang somewhere. I could verify that the real mode code up to the assembly code in pmjump.S is in fact executed. The problem appears to occur while enabling protected mode. I tried to put endless loops into the 32-bit setup code but these were apparently not reached. As far as I understand this, the protected mode jump in pmjump.S seems to jump into nowhere. I am willing to do tests with the XEN guest and send any additional information that might be helpful. However, I cannot change the XEN host at this time. Any suggestions? regards Christian