Re: [PATCH 4/6] kvm-userland.git mmu notifier compat

Andrea Arcangeli
2008-07-29T13:03:40Z

On Tue, Jul 29, 2008 at 03:49:08PM +0300, Avi Kivity wrote:
> Applied; thanks. I think page pinning can be worked around by pinning all
> pages on memslot registration (and unpinning on memslot removal); this will
> slow down virtual machine startup, but is at least simple.

This has the benefit that will also fix the tlb issues, but if we go
this way if a sles/rhel user takes the next kvm release, all ram will
be pinned and it won't swap anything for him, like with my patch that
added VM_LOCKED. Said that swap wasn't a reliable feature before so
nobody should have depended on that.

If we really go this memslot-wide-pinning way I could submit to rhel
and sles a mmu notifier backport so the rhel/sles users won't have to
wait to get their kernel upgraded to 2.6.27 to get full kvm-paging.