Messages in this thread | | | Date | Mon, 19 Aug 2019 08:25:52 +0200 | From | Borislav Petkov <> | Subject | Re: [PATCH 2/4] x86/vmware: Add a header file for hypercall definitions |
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On Mon, Aug 19, 2019 at 12:28:05AM +0200, Thomas Hellström (VMware) wrote: > Unfortunately we can't use it, because it's unconditionally set on AMD even > if the VMware hypervisor > doesn't support it (by version or by configuration).
AMD sets it because they don't support VMCALL. Nothing stops us from making that conditional depending on what the hypervisor can/supports. I'm thinking it would be even cleaner if we use those two flags:
X86_FEATURE_VMMCALL X86_FEATURE_VMCALL
to denote hw support for either one or the other instruction and switch accordingly. Just like KVM does.
In your case, the HV would set the preferred flag in arch/x86/kernel/cpu/vmware.c - just like the others do in their respective CPU init files - and the alternatives code would switch to it when it runs.
Or is there more? :)
Thx.
-- Regards/Gruss, Boris.
Good mailing practices for 400: avoid top-posting and trim the reply.
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