Comment 128 for bug 1518457

On review of the patch series, it's simply too large and complex to backport for this situation; it makes, and depends on, a rather large amount of change to the mm subsystem, and there are easier and smaller ways to work around this bug in the xenial kernel.

Specifically, a comparison of the Xen balloon driver vs. the virtio balloon driver shows an important difference; while the Xen balloon driver hot-adds memory as soon as it initializes, the virtio driver does not hot-add memory; it only adjusts its size to adjust the amount of free memory. Most importantly, the Xen balloon driver initially hot-adds memory but does not make any (except a very small amount) available for system use.

I'm looking at the Xen balloon driver to see how it can be changed to fix this bug.