[Xen-devel] [PATCH v4 2/7] xen/arm: introduce HYPERVISOR_platform_op on arm and arm64

[Ian Campbell]

On Fri, 2015-11-13 at 18:10 +0000, Stefano Stabellini wrote:
> 
> I agree with your point (I thought about it myself) but the current
> assembly scheme for hypercalls doesn't work well with that. I would have
> to introduce, and maintain going forward, two special hypercall
> implementations in assembly, one for arm and another for arm64, just to
> set interface_version. I don't think it is worth it; I prefer to have to
> maintain the explicit interface_version setting at the call sites (that
> today is just one).

You could give the bare assembly stub a different name (append _core or
_raw or something) and make HYPERVISOR_platform_op a C wrapper for it which
DTRT.

Ian.