Under a 3.16 based kernel (Ubuntu 3.16.0-031600-lowlatency), CardBus is not working unless pci=assign-buses is added to the kernel boot parameters. It was working OOTB on a 3.2 based kernel (Ubuntu 3.2.0-67-generic), and I have not thoroughly bisected what made it stop working.
Created attachment 148711 [details] Dmesg under working 3.2 kernel
Created attachment 148721 [details] Lspci -vvnn under working 3.2 kernel
Created attachment 148731 [details] lspci -vvnn under non-working 3.16 kernel
Created attachment 148741 [details] dmesg under non-working 3.16 kernel
Created attachment 149761 [details] dmesg (with dyndbg) under non-working 3.16 kernel
Created attachment 150151 [details] patch to revert fc1b253141b3 This is a test patch on top of v3.17-rc2 that reverts fc1b253141b3 ("PCI: Don't scan random busses in pci_scan_bridge()"). Please test and see if this fixes the problem.
Hi, I have now tested the revert patch on top of v3.17-rc5 and I can confirm that the cardbus port is now working. (Note: I did not test v3.17-rc5 without the patch reverted, so other things, including kernel configuration, could possibly have changed too, between this test and the former v3.16 test that exposed the bug.)
7a0b33d4a45d ("Revert "PCI: Don't scan random busses in pci_scan_bridge()"") appeared in v3.17-rc7 and should resolve this problem.