Comment 15 for bug 1022561

I hope the background was explained well enough in comment #11. For the experience I just tried a KVM VM 64bit which got 2G of memory. Without the patch in comment #12 the initial page tables are about 4M big. And neither with crashkernel= 28M nor with crashkernel=256M I was able to get the crash-kexec working. I wonder whether this is because of the page tables using up some memory range that is special.
But any way, with the patch, the initial page tables are only 16K and now crashkernel=128 is sufficient to make things work.