[libvirt] [Team2013] Integrating LiSA into libvirt

[Radu Rendec]

On Mon, 2013-09-16 at 11:02 +0100, Daniel P. Berrange wrote:
> Looking at the website it seems that it requires custom kernel
> branches, and the most recent kernel branch I see, with patches
> from last 2 months, is based on the pretty old 2.6.32 release ?
> The website also indicates the kernel<->userspace API is not
> ABI stable.

Unfortunately, our website is not up-to-date with the latest development
effort that has been put into the source code.

We've recently changed LiSA to be switching engine agnostic. Now it can
work with the "bridge" and "8021q" modules, which are part of the stock
linux kernel.

Our custom kernel module is "yet another engine" that LiSA supports, but
it's not a requirement.

> I must say I don't know all that much about networking. My main
> uninformed question would be how does this LiSA kernel support
> differ from/relate to OpenVSwitch which seems to be the technology
> the kernel community has decided upon for next generation network
> capabilities in Linux. I'm rather loathe consider support for new
> Linux networking features based on out-of-tree kernel patches.

I completely understand your point, but maybe you'll reconsider now that
you know an out-of-tree patch is not actually required.

As for our out-of-tree module, we actually tried to push it upstream a
couple of years ago, but the kernel networking team said that it didn't
make sense to add a new module with similar functionality to already
existing modules and that we should have fixed those instead (if
something had been wrong with them).

That was even before OpenVSwitch was released as open source. I'm
actually disappointed about this. LiSA was out in 2005 - that's 4 years
before OpenVSwitch, but nobody cared.

Regards,

Radu