Sorry to reply to my own message... but I wanted to add something.

Since I upgraded my kernel back around 2.6.16, I stopped seeing my SMBus
adapter on the PCI bus, and thus could not get readings from the LM90
sensor chip on my laptop.  After trying the pci=assign-busses parameter,
the error messages about transparent busses go away, but I still can't
access the SMBus controller (it uses the i2c-i801 module, in case that
helps).

I've attached the dmesg that I get when I specify that parameter; the
lspci output remains the same.

--Thomas Tuttle