Open Stack

On Mon, Mar 08, 2021 at 12:41:51PM -0300, Wainer dos Santos Moschetta wrote:
> Hi all,
> 
> While working on updating the version of QEMU [1] used on the project, for
> some occasions people outside asked me why the project builds QEMU from
> source instead of relying on distro's provided. When I started contributing
> to this project I asked it myself many times but I never looked for an
> answer.
> 
> I can think on many reasons but I would be guessing. So If someone could
> share the rationale here, I would appreciate it. Perhaps more important, we
> could discuss if the scenario stands the same so that we should stick with
> that approach or if we could manage the QEMU build differently nowadays.

I noticed that too while looking into kata-deploy a while ago.  I agree
using a standard build could remove a fairly major pain point and a
flexibility obstacle.

As for the reasons, unfortunately I can only guess as well but I noticed
kata tends to patch QEMU sources before it builds them.  If there are any
custom patches among the ones that are applied (as opposed to just, say,
backports of stuff from a higher QEMU version) that could explain the
custom build, at least partly.

In fact, even if the patches are just backports, it is conceivable that
kata needs to use a specific version of QEMU for some reason but also needs
some bits from a higher version, thus a custom build.

	pvl