Excellent job on the firewire support!
gallatin at cs.duke.edu
Wed Jul 21 08:04:23 PDT 2004
Doug Rabson writes:
> On Wed, 2004-07-21 at 15:41, Andrew Gallatin wrote:
> > Doug Rabson writes:
> > > 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.
> > Does remote access to physical memory require dcons to be loaded
> > on the target?
> No. The remote access to physical memory is a hardware-implemented
> feature of the firewire ohci hardware. Its enabled in fwohci_attach().
> In the long term, I would like to restrict this a bit but right now all
> you have to have is fwohci loaded on the target machine.
Yes, it seems like turning it off by default would be a good idea.
Its very handy for debugging, but the security implications are rather
Thanks for the info!
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