From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: Correct format for HVM graphics Date: Fri, 20 Apr 2012 12:28:03 -0400 Message-ID: <20120420162803.GA31062@phenom.dumpdata.com> References: <4F7C63EE.6000703@canonical.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <4F7C63EE.6000703@canonical.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Stefan Bader Cc: Stefano Stabellini , xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org On Wed, Apr 04, 2012 at 05:08:30PM +0200, Stefan Bader wrote: > Hi Stefano, > > quite a while back in time, you and Konrad had a discussion about some HVM setup > problems via libvirt. One part was graphics and the problem seemed to be that > when creating a new instance through xend for HVM, the use of vfb was wrong. It > mostly does work but then also defines a vkbd which takes a long time in the > xenbus setup to finally fail. So, this patch http://git.kernel.org/?p=linux/kernel/git/konrad/xen.git;a=commit;h=3066616ce23aad5719c23a0f21f32676402cb44b fixes it in the kernel (and I remembered this time to stick stable@kernel.org on it). It should eleviate some of the pains by making the timeout only 30 seconds when vkbd is used, instead of the lengthy 6 minutes. > > Because this was not a really fatal problem it did take a long time to actually > get back to it. But now I had a look and found that libvirt indeed does use the > vfb form for both the xen-xm and xen-sxpr formats (the latter being used to > create guests). The decision is made based on the xend version number in the HVM > case. Which would be wrong if I did understand your reply correctly. > > I have been testing a patch to libvirt, which would not use a vfb definition > whenever HVM is used (regardless of xend version). And it does seem to work (xm > list -l however has a vfb device definition, but the same happens when creating > the instance with a xm style config file that definitely has no vfb section in > it). But I am testing based on our 12.04 release which uses Xen 4.1.2. So I want > to make sure the solution for libvirt is correct for even the current Xen version. > > So in short, is this always correct? > > if (HVM or (PVM when xend is from xen < 3.0.4 / xend version < 3)) > do not define a vfb device > else /* PVM and xend version >= 3 */ > define a vfb device > > Thanks, > Stefan >