From mboxrd@z Thu Jan  1 00:00:00 1970
From: erik quanstrom <quanstro@labs.coraid.com>
Date: Fri,  8 Jul 2011 11:14:51 -0400
To: 9fans@9fans.net
Message-ID: <856dd0396cfa3bdef849de6d15d42da8@coraid.com>
In-Reply-To: <20110708061922.1CEB3B827@mail.bitblocks.com>
References: <20110706184008.AC595B827@mail.bitblocks.com>
	<CALDPdrpH+G1VS_y5BvwgtmQsb1iLfx_c3VDeM1YeeyqJ6YLxKQ@mail.gmail.com>
	<20110708061922.1CEB3B827@mail.bitblocks.com>
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Subject: Re: [9fans] 9atom & virtualbox 4.0.10 networking issue
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On Fri Jul  8 02:21:12 EDT 2011, bakul@bitblocks.com wrote:
> On Thu, 07 Jul 2011 09:10:49 +0800 Fernan Bolando <fernanbolando@mailc.net>  wrote:
> >
> > This allows the host to drawterm to the virtual machine. I failed to
> > get it to work as NAT or Bridge. Running the nic as host only is ok if
> > you just want to run plan9 without internet access.
> >
> > I hope you get NAT or host running. It would  be nice.
>
> With Erik's help I tried various things. As per his suggestion
> hardwiring igbe's irq to 9 made networking work (adding
>     ether0=type=igbe irq=9
> didn't work).  While he was trying to figure out the irq
> problem, I accidentally stumbled upon the "right" solution.

the problem is in the $PIR routing.  there is the correct entry
mapping irq 10 -> 9, but it does the mapping for 0.7.0, the acpi fn,
and not 0.3.0.  there isn't a lot of organized documentation on the quirks
of $PIR routing, and most other implementation are so riddled
with workarounds that it's hard to tell for a desk check (i don't
have a mac) why they might accidently work.

i suspect the $PIR link for acpi and for the nic are the same.
devices with the same link need to apply the same mapping.
it's a bug in the $PIR table, but this is a bug handled by so
many oses, it's not clear that the vbox guys would know about
the problem.

if this is the case, a small reorg of the $PIR handling code
should be able to recognize and handle this case.  if someone
could send me a dump of a problematic vbox $PIR table that would
be great.  you can dump it by changingthe if(0) to if(1) in
pci.c:/^pcirouting\( — /sys/src/9/pc/pci.c:811,813.

> Thanks to Erik for all his help.

no problems.  too bad it still doesn't work quite right.

- erik