Re: [PATCH 12/15] hyperv: move VMBus connection ids to uapi

[Roman Kagan]

On Mon, Jan 09, 2017 at 12:40:48AM -0800, hpa@xxxxxxxxx wrote:
> On January 9, 2017 12:32:23 AM PST, Roman Kagan <rkagan@xxxxxxxxxxxxx> wrote:
> >On Mon, Jan 02, 2017 at 09:19:57AM +0100, Paolo Bonzini wrote:
> >> On 28/12/2016 18:09, Roman Kagan wrote:
> >> > Am I correct assuming that QEMU is currently the only user of
> >> > arch/x86/include/uapi/asm/hyperv.h?
> >> > 
> >> > Then I think we're fine withdrawing it from uapi as a whole and
> >letting
> >> > QEMU pull it in through its header-harvesting scripts (as does now
> >> > anyway).  This would lift all licensing and longterm API stability
> >> > expectations.
> >> 
> >> Actually, QEMU's header-harvesting scripts use uapi/ headers
> >> exclusively, since they are built on "make headers_install".
> >> 
> >> The extra cleanups that QEMU does on top are to allow compilation of
> >the
> >> headers on non-Linux machines.  They don't really do much more than
> >> changing Linux (linux/types.h) integer types to the C99 (stdint.h)
> >> equivalents.
> >
> >Ouch, I stand corrected.
> >
> >So what should we do with it then?  I'm sorta lost...
> >
> >We certainly can give it up and live with a private copy of the
> >definitions in the QEMU tree but that doesn't sound optimal in any
> >sense.
> >
> >Thanks,
> >Roman.
> 
> Why do that through header mangling rather than typedef?

Sorry for not being clear, I actually asked what to do with the Hyper-V
and VMBus protocol definitions.

The typedef vs mangling is a different matter; I guess mangling was
chosen to avoid conflicts with system-provided definitions on non-Linux
systems, but I think Paolo can tell more.

Roman.