Re: [Qemu-devel] virtio-gpu doesn't build if you do a linux-headers update from kvm/next

[Peter Maydell]

On 5 November 2015 at 17:15, Laszlo Ersek <address@hidden> wrote:
> --*--
>
> I think we had the same discussion when Wei was working on SMBIOS 3.0
> for ARM. In
> <http://thread.gmane.org/gmane.comp.emulators.qemu/353282/focus=354806>,
> you asked
>
> "Is support for this all in the mainline kernel yet?"
>
> I didn't really understand that question -- it didn't matter. QEMU as a
> *platform* was learning how to provide a service that was governed by an
> industry standard. The status of *guest* kernel support (and of guest
> utility support) was irrelevant, in my opinion.

The reason for the question in that case was slightly different.
As you say, it would be OK to implement support in either the
kernel or QEMU first. I asked because:
 (1) I felt I had no understanding of the relevant spec to be able
to correctly review the QEMU code changes in detail
 (2) I did trust that people on the kernel mailing list would be
able to provide review at that level of detail
 (3) I was therefore trying to "outsource" the review to the
kernel folks so I could rely more on "QEMU works with the kernel"
as a check on the QEMU patches without falling into the trap
of "both sets of patches have complementary bugs that cancel each
other out".

with a side order of
 (4) if a spec isn't important enough to get support in Linux then
it's at least worth asking whether it's important enough to support
in QEMU.

thanks
-- PMM