In a short discussion following a patch titled "fix abdhid mismerge", Al Viro noted troubles in tracking down the changeset that caused the problem, "what's the right way to trace the things like that? Linus?" Linus Torvalds, as the original author of git, replied, "in general, I'm afraid that merge errors are simply not very easy to find." He then offered some general tips for tracking down mis-merges, noting, "if anybody can come up with a better way to find these kinds of mis-merges, I'd love to hear about it." In regards to this particular case, he explained:

"'-c' is for regular combined merges: any file that was modified in both parents will show up as a combination of the diffs of both sides, while a file that was taken in its *entirety* is ignored.

"In this case that's exactly what you wanted. It's just too noisy to necessarily be the default, and you can still have a silent mis-merge if the merger picked *only* one side.

But in general, I suspect that '-c' is often a good thing to try if you cannot find the cause of some change in a regular commit, and suspect a merge error."

Andrew Morton [interview] sent out the latest lguest patches for review, noting that he intends to merge the code into the mainline kernel, "some concern was expressed over the lguest review status, so I shall send the patches out again for people to review, to test, to make observations about the author's personal appearance, etc. I'll plan on sending these patches off to Linus in a week's time, assuming all goes well." The project's FAQ notes, "lguest is designed to be simple to use and modify, with the aim of keeping the codebase small. Currently it's around 5000 lines including userspace utility, whereas kvm is over 10 times that size, and Xen is around 10 times bigger again (of course, both have far more features)."

The lguest patches are written and maintained by Rusty Russell [interview] who also authored Rusty's Remarkably Unreliable Guide to Lguest, the project's documentation. The guide explains, "lguest is designed to be a minimal hypervisor for the Linux kernel, for Linux developers and users to experiment with virtualization with the minimum of complexity. Nonetheless, it should have sufficient features to make it useful for specific tasks, and, of course, you are encouraged to fork and enhance it." In the FAQ, lguest is compared to kvm [story], "kvm requires hardware virtualization support (most recent Intel and AMD chips have it), but it can run almost any Operating System (since it does full virtualization. It also has 64-bit support. Lguest doesn't do full virtualization: it only runs a Linux kernel with lguest support." The FAQ also compares lguest to Xen, "Xen is similar, in that it doesn't need hardware virtualization support (although it can use it), but Xen supports an extensive range of features such as PAE (ie. lots of memory), SMP guests, 64-bit. You have to boot your kernel under the Xen hypervisor; you can't simply modprobe when you want to create a guest."