Re: [PATCH] vhost: fix MQ fails to startup

[Yuanhan Liu <yuanhan.liu@linux.intel.com>]

On Fri, Apr 28, 2017 at 09:57:20AM +0200, Maxime Coquelin wrote:
> >>>Maybe we could introduce a version message? With that, we could tell
> >>>whether the frontend has fixed the known bug or not.
> >>
> >>That's a possibility, but this is not really the role of a protocol
> >>version. As in this case, the protocol does not change, just an
> >>implementation.
> >
> >Maybe. Well, you might could think this way: we do increase the version
> >when we make a new release (with bugs being fixed).
> >
> >Or, we could also make the version two parts: major and minor. We increase
> >major for major updates (say, new features, etc). We increase minor for
> >bug fixes.
> >
> >The only thing that doesn't make too much sense is the bug is actually
> >from the QEMU implementation but not from the vhost-user spec.
> 
> Yes, I was maybe not clear, but that's what I meant when saying that was
> not the role of the protocol version.

Yes, I realized it later: I overlooked it. Sorry.

> >Talking
> >about that, it may make more sense to introduce a new message to carry
> >the frontend version, something like a string "QEMU v2.8".
> 
> I don't think this is a good idea as it would create more problems that it
> would solve. Indeed, you would need also the distro version, as for
> example, Red Hat could backport the fix in its QEMU v2.6 package, Ubuntu
> in its v2.7, etc...

I have thought of stable release, say "QEMU v2.8.1". But you are right,
it got way more complex when distro backport is considered :(

	--yliu