Makes sense. And, at the end of the log, I see Sep 21 12:26:44 jlinn kernel: watchdog: BUG: soft lockup - CPU#12 stuck for 22s! [mtp-probe:903] and the corresponding one is: Sep 21 12:26:20 jlinn mtp-probe[903]: checking bus 1, device 3: "/sys/devices/pci0000:00/0000:00:14.0/usb1/1-7"