Messages in this thread | | | Subject | Re: selftests/x86/fsgsbase_64 test problem | From | "H. Peter Anvin" <> | Date | Mon, 29 Jan 2018 10:30:05 -0800 |
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On 01/29/18 10:26, Andy Lutomirski wrote: >>> >>> That will utterly suck on non-UMIP machines that have >>> hypervisor-provided UMIP emulation. >> >> Is that a valid thing to optimize for, especially given that paranoid >> entries aren't the most common anyway? > > A bunch of people seem to care about NMI performance for perf. >
That wasn't really the question...
> And the current patch set works without this trick.
But I believe the tricks it uses are fragile.
> FWIW, if we switch all entries to the entry text trampoline, we get direct percpu access for free.
That might be a better option.
-hpa
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