Comment 16 for bug 999462

I have to retract my statement. I'm using a Lenovo x220.
Disabling "PCI Express Power management" (Config -> Power) via Bios resolves the issue for me. Before Ubuntu became unresponsive (like the card is throwing a lot of interrupts) after the *2nd* hot-plug, first one seems fine though. On AC or Battery did not change the behavior.

Also I noticed "ACPI FADT declares the system doesn't support PCIe ASPM" in dmesg, so I'm not sure this bug is even related. I leave it here for people who have similar issues :)