From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Wright Subject: Re: VM hangs during boot on 3.0.4 dom0 kernel, works on alternative hardware Date: Tue, 13 Sep 2011 10:52:40 +0100 (BST) Message-ID: <8813601.2.1315907560404.JavaMail.root@zimbra.overnetdata.com> References: <4E6BCDA9.3030700@overnetdata.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4E6BCDA9.3030700@overnetdata.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Konrad Rzeszutek Wilk Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org ----- Original Message ----- > On 06/09/2011 17:16, Konrad Rzeszutek Wilk wrote: > > On Mon, Sep 05, 2011 at 11:31:16AM +0100, Anthony Wright wrote: > >> I have two machines with identical Dom0's and DomUs, but different > >> hardware. The Dom0 has a patch which I produced myself based on the > >> "Re: > >> [Xen-devel] Kernel bug from 3.0 (was phy disks and vifs timing out > >> in > >> DomU)" thread. The patch calls vmalloc_sync_all after every > >> alloc_vm_area, and I realise this isn't the best solution, but it > >> allowed me to move forward. > > > >> The patch fixes the problem I had on one machine, so that now the > >> VMs > >> boot correctly, but I have another system with an identical setup > >> (identical Dom0 & DomU kernels, identical startup for DomU) and the > >> VM > >> fails to start. I have attached a copy of the console log from the > >> good > >> VM and the bad VM. > > And what does the dom0 and xen hypervisor log give you? > > > > It looks to be hanging at identifying the CPU - is the hardware > > quite different from one setup to another? Have you toyed with > > using the cpuid flag in the guest to mimic the lowest CPU type? > I've found a solution to my problem. The PV DomU was running a 32 bit > linux kernel version 2.6.30.1. I hoped that a new kernel would be able > to handle to CPU more effectively, and so I upgraded my DomU kernel to > 3.0.4, and now the DomU boots. > > This solves the problem for me, but I'm slightly concerned that my > original kernel wouldn't work with this CPU (the CPU type for the > kernel > builds is set to Pentium Pro). I'll try the 2.6.30.1 kernel on bare > metal on monday to try to see if this is a xen/Dom0 kernel issue or a > CPU/DomU issue. > > Anthony I've tried the 2.6.30.1 kernel on bare metal and it boots correctly, so it looks like some xen/Dom0 interaction is causing it to fail when run as a DomU. I have a work around (upgrading to 3.0.4 kernel), so it's not affecting me but I'm happy to do any diagnostics to help identify the cause of the problem.