Re: Consuming PCI device in PV kernel

[Simon Martin <furryfuttock@gmail.com>]

Hello Dario,

> BTW, how's this going (if I can ask)? Any exciting news about this you
> can share with the community? :-)

Nothing   exciting   I'm   afraid,   just   lots  of  donkey work. The
micropv  project (similar to the Xen mini-os but a LOT lighter with no
dynamic   memory,   paging  etc)  is  coming  along  nicely.  Lots  of
improvements   about   talking   to   the  hypervisor and xenstore and
making  it  more implementation agnostic. The mirage-os guys seemed to
be interested in this when I first mentioned it. No idea if they still
are, it's been a while. Too many projects, too little time ;-)

My  PV  OS  is  sitting  quite  nicely in the hypervisor and I have my
context  switch  running  nicely  within  the  micropv.  One problem I
haven't  been  able  to  work  around  so  far is implementing lazy FP
context recovery, I do it on every context switch. This is crazy but I
get  FP  exceptions if I don't. As I have larger fish to fry, this one
is just flagged as something to come back to.

I had to modify one of the existing Linux kernel drivers (gntalloc) to
provide  more  functionality.  I  got  it  to  a state in which it was
accepted  by  Daniel De Graaf the original implementor. I now have to
push it upstream the Linux kernel maintainers.

As  a  general  comment  I find that the existing Xen documentation is
fine  for handling existing HVM/PV domain implementations, but you are
on  your  own  when it comes to implementing your own PV. If it wasn't
for  the  good  will  of the people on this mailing list I would never
have  been  able  to  get  where I am now. I know that I am in a small
niche  here,  and the existing documentation is fine for 99% of people
who are using Xen. If this is something that should be documented then
I  would  be  willing  to  have  a  stab at writing some wiki pages if
someone can clean up the things that I have misunderstood.

Regards, and once again, a big thanks to everyone

-- 
Best regards,
 Simon                            mailto:furryfuttock@gmail.com