Nice idea. Problem with that is that approach is that we don't have
full control here. It probably isn't that a hard to have vmware, xen
and kvm agree here, given vmware proposes this and for xen+kvm one can
send patches. But even that you can't take for granted, see the
discussion of the "tsc-may-change-on-migration" problem.
The real big problem are other closed-source hypervisors (VirtualPC /
Hyper-V / Parallels / ...). How can we be sure they don't define that
leaf to something different?
The fudamental issue outlined above aside: Even the "ignore 0" part
isn't in the patch right now.
Yes.
pv drivers in hvm guests use that (and query very xen-specific stuff
which wouldn't make much sense in other hypervisors). It isn't in the
kernel source tree, look here instead:
http://xenbits.xensource.com/xen-3.3-testing.hg?file/19201eebab16/unmodified_drivers/l...
cheers,
Gerd
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