beige g3 rage II xf4.0.1 and miBoot

[Michel Lanners]

On  28 Sep, this message from Kostas Gewrgiou echoed through cyberspace:
> PS> Any ideas why writing to a disabled pci device in ppc crashes
> the machine but not the x86 ones ? Is this something that can be fixed
> in the kernel or an arch thing ?

Accessing config registers or device resources?

Accessing config registers should work ok, if not, there's something
_really_ wrong somewhere.

Accessing resources that are not enabled, yes, you get a machine check,
because the device will not answer your accesses, so the bus will hit a
timeout, which will be signaled to the processor (was that a PCI master
abort?), in a way that the processor will throw a machine check
exception.

And that machine check exception is not recovered from (would that even
be possible?), hence a plain old kernel panic.

Michel

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