George Dunlap

I received my PhD from the University of Michigan in December 2006. I joined XenSource in May of 2006. I've been working on analyzing performance in the Xen hypervisor. I'm currently working on a

George Dunlap
XSA-108: Not the vulnerability you're looking for
10/03/2014

There has an unusual amount of media attention to XSA-108 during the embargo period (which ended Wednesday) — far more than any of the previous security issues the Xen Project has reported. It began when a blogger complained that Amazon was telling customers it would be rebooting VMs in certain regions

The Docker exploit and the security of containers
06/23/2014

We normally only cover news and information directly related to Xen in this channel, but we thought it might be useful to briefly expand our scope a bit to mention the recent discussion about the Docker security exploit. What’s the news? Well to begin with, a few weeks ago

Release management: Risk, intuition, and freeze exceptions
06/19/2014

I’ve been release coordinator for Xen’s 4.3 and 4.4 releases. For the 4.5 release, I’ve handed this role off to Konrad Wilk, from Oracle. In this blog, I try to capture some of my thoughts and experience about one aspect of release management: deciding

Xen 4.4 Released
03/10/2014

Xenproject.org is pleased to announce the release of Xen 4.4.0. The release is available from the download page: * Xen 4.4.0: Download, Source (tag RELEASE-4.4.0), release notes. Xen 4.4 is the work of 8 months of development, with 1193 changesets. It’s our

Ballooning, rebooting, and the feature you've never heard of
02/14/2014

Today I’d like to talk about a functionality of Xen you may not have heard of, but might have actually used without even knowing it. If you use memory ballooning to resize your guests, you’ve likely used “populate-on-demand” at some point.  As you may know, ballooning

Xen 4.3.0 released!
07/09/2013

Xenproject.org is pleased to announce the release of Xen 4.3.0. The release is available from the download page: * Xen 4.3.0: Download, Source (tag RELEASE-4.3.0), release notes. Xen 4.3 is the work of just over 9 months of development, with 1362 changesets containing

Security vulnerability disclosure process accepted
06/17/2013

Last week the proposed changes to the security policy were approved unanimously by the Xen committers; the policy has been updated accordingly. What this means is that now if you are “public hosting provider”, “vendor of Xen-based system”, or a “distributor of operating systems with Xen support”, regardless of your

Xen 4.3 update: Code Freeze started
04/22/2013

Just a quick update — we have passed the feature freeze, and are now beginning the code freeze, in our schedule to get Xen 4.3 out by mid-June. Is say “beginning the code freeze” because it is still possible to get new code in for a short time now; but

Request for input: Extended event channel support
03/27/2013

The following has been posted on the xen-devel and xen-users mailing lists. Executive summary The number of event channels available for dom0 is currently one of the biggest limitations on scaling up the number of VMs which can be created on a single system. There are two alternative implementations we

Xen 4.3 mid-release roadmap update
02/11/2013

At XenSummit in August, I talked about the new planning process that Xen.org is experimenting with. This is apparently a pretty hot topic, as that presentation on slideshare.net has received over 72,000 views! We’re about half-way through the planned 4.3 development cycle, and while I’

Security disclosure process discussion update
12/17/2012

After concluding our poll about changes to the security discussion, we determined that “Pre-disclosure to software vendors and a wide set of users” was probably the best fit for the community. A set of concrete changes to the policy have now been discussed on xen-devel (here and here), and we

The Paravirtualization Spectrum, Part 2: From poles to a spectrum
10/31/2012

In part 1 of this series, I introduced the concepts of full virtualization and paravirtualization (PV), as well as the hardware virtualization (HVM) feature used by Xen (among other things) to implement full virtualization. I also introduced the concept of installing paravirtualized drivers on a fully virtualized system. This small