Messages in this thread | | | Date | Wed, 1 Nov 2017 21:42:42 +0100 | From | Borislav Petkov <> | Subject | Re: [PATCH 01/23] x86, kaiser: prepare assembly for entry/exit CR3 switching |
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On Wed, Nov 01, 2017 at 11:27:48AM -0700, Dave Hansen wrote: > This allows for a tiny optimization of Andy's that I realize I must have > blown away at some point. It lets us do a 32-bit-register instruction > (and using %eXX) when checking KAISER_SWITCH_MASK instead of a 64-bit > register via %rXX. > > I don't feel strongly about maintaining that optimization it looks weird > and surely doesn't actually do much.
Yeah, and consistent syntax would probably bring more.
> Thanks for catching that. We can kill one of these. I'm inclined to > kill the first one. Looking at the second one since we've just saved > off ptregs, that should make %rdi safe to clobber without the push/pop > at all. > > Does that seem like it would work?
Yap, sounds about right.
Thx.
-- Regards/Gruss, Boris.
Good mailing practices for 400: avoid top-posting and trim the reply.
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