randomly all usb devices will disconnect, then reconnect a few seconds later. this will manifest as keyboard and mouse not responding, file transfers dying, etc
this is because linux wants to turn usb ports off to "save power" without actually checking things like "are they being used" or "should this ever be allowed to be turned off"
the cure is to open up /etc/default/grub, add "usbcore.autosuspend=-1" to the end of the line beginning GRUB_CMDLINE_LINUX_DEFAULT. do update-grub or whatever the equivalent is on your distro and reboot
posting this because after over a year this buggy kernel feature still hasn't been fixed and randomly manifested itself to me yesterday
