Re: [patch 00/21] Xen-paravirt: Xen guest implementation for paravirt_ops interface
From: Rusty Russell <hidden>
Date: 2007-02-17 05:06:35
Also in:
lkml, xen-devel
From: Rusty Russell <hidden>
Date: 2007-02-17 05:06:35
Also in:
lkml, xen-devel
On Fri, 2007-02-16 at 13:48 -0800, Zachary Amsden wrote:
Christoph Lameter wrote:quoted
It still seems to be implemented for Xen and not to support a variety of page table methods in paravirt ops.Yes, but that is just because the Xen hooks happens to be near the last part of the merge. VMI required some special hooks, as do both Xen and lhype (I think ... Rusty can correct me if lhype's puppy's have precluded the addition of new hooks).
lguest was supposed to be a demonstration of paravirt_ops, so it shouldn't have added any. But note that I did change some other things, such as the esp0 initialization for the swapper. Puppies are still alive and well. Although Andi not pushing into 2.6.21 (yet?) made puppies sad 8(
Xen page table handling is very different, mostly it is trap and emulate so writable page tables can work, which means they don't always issue hypercalls for PTE updates, although they do have that option, should the hypervisor MMU model change, or performance concerns prompt a different model (or perhaps, migration?)
Yes, Xen really like their direct pagetable stuff. I'm a traditionalist, myself, but it did require some expansion of paravirt_ops. KVM might well want more, although from here it's more likely we'll move some of the hooks up the stack a little IMHO. Cheers, Rusty.