Messages in this thread | | | Date | Tue, 20 Aug 2019 15:42:57 +0200 (CEST) | From | Thomas Gleixner <> | Subject | Re: [PATCH 2/4] x86/vmware: Add a header file for hypercall definitions |
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On Tue, 20 Aug 2019, Thomas Hellström (VMware) wrote:
> On 8/20/19 1:32 PM, Peter Zijlstra wrote: > > On Sun, Aug 18, 2019 at 04:33:14PM +0200, Thomas Hellström (VMware) wrote: > > > > > +#define VMWARE_HYPERCALL \ > > > + ALTERNATIVE_2(".byte 0xed", \ > > > + ".byte 0x0f, 0x01, 0xc1", X86_FEATURE_VMW_VMCALL, \ > > > + ".byte 0x0f, 0x01, 0xd9", X86_FEATURE_VMW_VMMCALL) > > For sanity, could we either add comments, or macros for those > > instrucions? > > Hmm. Here I followed and slightly extended what was done in asm/kvm_para.h. > > What confuses me a bit is, if it's clarity we're after, why don't people use > > #define VMWARE_HYPERCALL \ > ALTERNATIVE_2("inl (%%dx)", \ > "vmcall", X86_FEATURE_VMW_VMCALL, \ > "vmmcall", X86_FEATURE_VMW_VMMCALL) > > Seems to build fine here. Is it fear of old assemblers not supporting, for > example vmmcall
The requirement for binutils is version >= 2.21. If 2.21 supports vmcall and vmmcall all good.
Thanks,
tglx | |