Hi, What sort of kernel is this? Looks like there are some stream-related xhci_hcd bugs here. You may have more luck with UAS disabled if you need this system working ASAP. Not only SMART is failing, but also ordinary block reads and maybe writes as well, so it could potentially be a risk of data loss. For debugging, it would help to have a reliable trigger, like "happens every time I run smartctl manually" or "every time I do it while 'cat /dev/sdc >/dev/null'" or at least "often while <some workload>". I am able to find the PCI adapter responsible for a USB bus like this: $ ls -d /sys/bus/pci/devices/*/usb8 /sys/bus/pci/devices/0000:02:00.0/usb8 Regards, Michal
