Hi,
I've seen other systems where some PCI busses have only memory space enabled.
The ahc driver seems to be able to deal with this (at last the adapter
can be mapped in memory space) but it's disabled (see ahc_pci.c)
When it's enabled the machine panics with a uvm_fault() in a place which
shouldn't happen (and is by no way related to registers).

I tried a hacked kernel to force the driver to use memory space instead of
I/O space for ahc, and it didn't panic on my machine.

--
Manuel Bouyer <bouyer@antioche.eu.org>
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