RE: [PATCH 1/6] x86/tdx: Support hypercalls for TDX guests on Hyper-V

From: Dexuan Cui
Date: Tue Nov 22 2022 - 20:56:30 EST


> From: Dexuan Cui
> [...]
> The existing asm code for __tdx_hypercall() passes through R10~R15
> (see TDVMCALL_EXPOSE_REGS_MASK) to the (KVM) hypervisor.
>
> Unluckily, for Hyper-V, we need to pass through RDX, R8, R10 and R11
> to Hyper-V, so I don't think I can use the existing __tdx_hypercall() ?

I'm checking with the Hyper-V team to see if it's possible for them
to not use RDX and R8, and use R12 and R13 instead. Will keep the
thread updated.