Re: Again: (self)hosted Plan9? Was: [9fans] extending xen to allow

[Lucio De Re <lucio@proxima.alt.za>]

> It's not that drivers are fundamentally hard. It's that the hardware
> we work with is undocumented crap. Linux drivers know all the secrets;
> we're riding on that knowledge.

And so do millions more, perfectly understandably.  The problem is
that "all the world is Linux" is not a good mantra.  Porting drivers
from Linux to, say, NetBSD is a nightmare, multiplied by the number of
useful target OSes.  Whereas XEN largely suffers (only) from
inefficiencies accessing the lower layer, whenever it (and you, if I
understand your recent discussions) tries to punch through the
barrier, the mysteries strike again.

(In passing, I was looking at ISDN adapter drivers with a view to
implementing the functionality under NetBSD.  The Linux driver, in my
opinion, was orders of magnitude better coded than the FreeBSD
version.  Take that any way you like, it has changed my opinions on
Open Source device driver developers.)

To return to the main issue, I think effort applied towards
documenting "undocumented crap" would have a wider scope than adopting
or reverse engineering the knowledge in Linux drivers code.  The
latter is certainly a more immediate objective.  Of course, one then
also needs to deal with binary-only drivers and other such stumbling
blocks, but my hope would be that eventually hardware manufacturers
will get the message or will get deselected :-)

Given the choice between using Linux kernel source as the
documentation, versus Plan 9 kernel source, there are too many good
reasons to pick the Plan 9 option to list them here, where they are in
any case taken for granted.  Hence my preference for a 9load-type BIOS
on which others besides Plan 9 can build.

(The philosophy, probably flawed, is that Open Source principles are
"right" in some transcendent way and that a "good" manufacturer cannot
continue to overlook the benefits of being on the "right" side of the
line.  Communism had the same underlying principle and landed up on
the scrap-heap of history.)

++L