The following fixed the problem for my USB 3 Expresscard (NEC uPD720200):
sudo echo acpiphp >> /etc/modules:
Modify /etc/default/grub to have:
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash pciehp_force=1 pciehp_poll_mode=1"
and run
sudo update-grub
Now hotplugging works as expected.
The following fixed the problem for my USB 3 Expresscard (NEC uPD720200):
sudo echo acpiphp >> /etc/modules:
Modify /etc/default/grub to have:
GRUB_ CMDLINE_ LINUX_DEFAULT= "quiet splash pciehp_force=1 pciehp_poll_mode=1"
and run
sudo update-grub
Now hotplugging works as expected.