From: Thomas Gleixner <redacted>
Sent: Thursday, December 16, 2021 10:13 PM

quoted

Yes, this is the 3rd open that I asked in another reply. The only restriction
with this approach is that the sync cost is added also for legacy OS which
doesn't touch xfd at all.

You still can make that conditional on the guest XCR0. If guest never
enables the extended bit then neither the #NM trap nor the XFD sync
are required.

But yes, there are too many moving parts here :)

Yes. Many moving parts but in general it's getting cleaner and simplified. 😊

We just sent out v2 to hopefully lock down already-closed opens. Based on
that we can see what remains to be further solved.

And really appreciate all the suggestions from you and Paolo!

Thanks
Kevin