From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeremy Fitzhardinge Subject: Re: Re: [PATCH] xen: mask XSAVE in cpuid since we don't allow guests to use it Date: Wed, 11 Mar 2009 18:21:22 -0700 Message-ID: <49B86392.1000502@goop.org> References: <49B7E22F.40004@goop.org> <814026.1960.qm@web56103.mail.re3.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Andrew Lyon Cc: bderzhavets@yahoo.com, Xen-devel , Keir Fraser List-Id: xen-devel@lists.xenproject.org Andrew Lyon wrote: > On Wed, Mar 11, 2009 at 4:27 PM, Boris Derzhavets wrote: > >> It's not so important for me. The important thing is:- >> >> CentOS 5.2 PV DomU may be loaded only the very first time under Suse's >> 2.6.27 xen-ified kernel & Xen Unstable ( the most recent). Attempt to >> shutdown and start it again gives VBD cannot be connected . Hotplug scripts >> not working. That's a core issue, same behavior as under 2.6.29-rc7 (with >> XSAVE patch ). Kernel doesn't seem to be a root cause. >> I believe Xen unstable is broken in some way. >> >> Boris. >> > > This sounds very much like the problem I described in thread subject > "domain id number on xen unstable", I maintain my own 2.6.27 dom0 > kernel using opensuse Xen patches which I rebase to apply to vanilla > without the many other patches opensuse usually applies to the kernel > tree, so from a Xen point of view I am using a very similar kernel to > yours, I found that I could start a hvm but after shutting it down > attempting to restart it would fail or hang, sometimes I got hotplug > error that vbd could not be connected. > > The script that has problems on my system is xen-hotplug-cleanup , the > first time it is run it puts a lock in /var/run/xen-hotplug and never > removes it, so the next time the script runs it blocks waiting for the > lock and eventually times out. > > The offending line in the script is: > > vm=$(xenstore-read "/local/domain/${path_array[2]}/vm") > > putting a echo immediately after that line shows that nothing after it > is executed, which is why the lock is not released. > > replacing xen-hotplug-cleanup and xen-hotplug-common with the ones > from 3.3.1 seems to help, but after starting and stopping a few vm's > the entire system reboots, so I think some objects are not being > cleaned up, not surprising really, can hardly expect scripts to work > with the wrong version of Xen. > > This problem has got me stuck into a nasty corner, only Xen unstable > can fit our virtualization requirements (need viridian for stable > windows smp), but the Xensource kernel is too old for our hardware. > > I am going to put some serious effort into debugging this in the next few days. > Change 19242:226031d62fc5 is the last one which works for me. I haven't managed to bisect which specific change the problem starts occuring in, but 19250:b3774712e654 seems like a good starting point. J > Andy > > >> >> --- On Wed, 3/11/09, Jeremy Fitzhardinge wrote: >> >> From: Jeremy Fitzhardinge >> Subject: Re: [Xen-devel] Re: [PATCH] xen: mask XSAVE in cpuid since we don't >> allow guests to use it >> To: bderzhavets@yahoo.com >> Cc: "Xen-devel" , "Keir Fraser" >> >> Date: Wednesday, March 11, 2009, 12:09 PM >> >> Boris Derzhavets wrote: >> >>> Blktap helps out for multiple CentOS PV DomU restarts (with image on FS) >>> >> under Suse's 2.6.27 xen-ified kernel & Xen Unstable ( the most recent). >> >>> But it seems not implemented yet for 2.6.29-rc7 >>> >>> >> So your conclusion is that there's a regression in the tools stack when >> using blkback rather than blktab? >> >> J >> >> >> _______________________________________________ >> Xen-devel mailing list >> Xen-devel@lists.xensource.com >> http://lists.xensource.com/xen-devel >> >> >> > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel >