Xen.org and the Saga of the PVOps Dom0 Kernel
A new legend is growing within the Xen.org community on the PVOps Dom0 Kernel and its current mysterious status. In fact, this kernel is becoming so famous that I receive emails weekly from the community to learn more about its whereabouts. So what is the story?
The short answer is that the PVOps Dom0 kernel is the active development xen-unstable tree for the next version of Xen, which I refer to as Xen 4.0, shipping in Q1 2010. The long answer comes directly from Jeremy Fitzhardinge in the xen-devel newsgroup with a posting on the 18th this month at http://markmail.org/thread/nl2wyvqz2356fjq4.
Jeremy’s posting:
Well, my current pvops/dom0 tree is finally (reasonably) stable. There was a fairly nasty bug which ended up corrupting dom0 memory when doing IO on behalf of domains, but that is finally fixed.
In honour of this, I’ve renamed the rebase/* branches to xen/* (moving the old remaining xen/* branches to xen-old/*); xen/master is now the preferred branch for fetching current dom0 work.
The kernel tree is fairly featureful:
* basic dom0 support
* blkback
* netback
* ACPI power management
* S3 suspend/resume (at least for some people)
* microcode update
* MSI support
In other words, it has as much as it ever has.
There are a few notable missing features:
* blktap2
* netchannel2
* pci front/back
* upstream Linux support
* your pet feature
Full coordinates are:
git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git xen/master
See http://wiki.xensource.com/xenwiki/XenParavirtOps for general directions on configuration, compilation and use.
This is definitely a work-in-progress kernel. I’d appreciate all bug *and* success reports so I can get some idea of how many people are using this thing, and how often there are problems. Patches gratefully accepted.
As you can see, this kernel is in active development and test within the community and is a major priority for testing and feature development. If you have spare cycles and would like to help, this is where Xen.org needs your efforts. As for the mysterious status – I hope this answers everyone’s questions as the main development effort is on this kernel and is the future of Xen.org.
For more details on the kernel and its saga, checkout the video from Jeremy Fitzhardinge at http://vimeo.com/6168143.