Date: Thu, 22 Jul 2004 23:16:13 -0700 From: John-Mark Gurney <gurney_j@resnet.uoregon.edu> To: Doug Rabson <dfr@nlsystems.com> Cc: Andrew Gallatin <gallatin@cs.duke.edu> Subject: Re: Excellent job on the firewire support! Message-ID: <20040723061613.GH991@funkthat.com> In-Reply-To: <200407182104.53221.dfr@nlsystems.com> References: <16634.47272.768935.436137@grasshopper.cs.duke.edu> <200407182039.10773.dfr@nlsystems.com> <16634.54674.966908.540880@grasshopper.cs.duke.edu> <200407182104.53221.dfr@nlsystems.com>
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Doug Rabson wrote this message on Sun, Jul 18, 2004 at 21:04 +0100:
> > 4) Does the loader know about dcons? Eg, can I do "unload <ret> boot
> > kernel.test" using dcons?
>
> Actually thats the only downside of dcons. It doesn't cut in until the
> firewire controller attaches. It relies on the fact that the fwohci
> driver allows access to physical memory from any node on the bus
> (implemeted in hardware so you can examine the memory of a hung
> machine). The dconschat program uses this feature to access the dcons
> ring buffers in the target machine.
>
> I could imagine a dcons driver in the loader which just enabled physical
> access and used some kind of loader trick to hand off the ring buffers
> to the kernel dcons driver. It doesn't exist though - say nice things
> to the author and he might find the time for it :-)
You guys might want to check out nextboot.. it's very nice utility
that I've been using in my recent kernel debugging... should do what
you need to do w/o loader knowing about dcons...
--
John-Mark Gurney Voice: +1 415 225 5579
"All that I will do, has been done, All that I have, has not."
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