Messages in this thread | | | Date | Thu, 9 Mar 2023 15:45:05 +0100 | From | Borislav Petkov <> | Subject | Re: [PATCH v5 06/14] x86/ioremap: Support hypervisor specified range to map as encrypted |
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On Thu, Mar 09, 2023 at 03:36:45PM +0100, Jörg Rödel wrote: > Yes, that is right. The key is mainly for the NMI entry path which can > be performance relevant in some situations. For SEV-ES some special > handling is needed there to re-enable NMIs and adjust the #VC stack in > case it was raised on the VC-handlers entry path.
So the performance argument is meh. That key will be replaced by
if (cc_vendor == CC_VENDOR_AMD && cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT)
which is something like 4 insns or so. Tops.
Haven't looked yet but it should be cheap.
-- Regards/Gruss, Boris.
https://people.kernel.org/tglx/notes-about-netiquette
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