I assume that the generated list is a tree, so each leaf (Device/If) is on only one point. I note this output: $ lsusb -tv /: Bus 001.Port 001: Dev 001, Class=root_hub, Driver=xhci_hcd/16p, 480M ID 1d6b:0002 Linux Foundation 2.0 root hub [trimmed] |__ Port 004: Dev 004, If 0, Class=Hub, Driver=hub/4p, 480M [trimmed] |__ Port 005: Dev 006, If 0, Class=Hub, Driver=hub/4p, 480M [trimmed] |__ Port 006: Dev 019, If 0, Class=Hub, Driver=hub/4p, 480M ID 2109:2817 VIA Labs, Inc. /: Bus 002.Port 001: Dev 001, Class=root_hub, Driver=xhci_hcd/10p, 10000M [trimmed] |__ Port 006: Dev 006, If 0, Class=Hub, Driver=hub/4p, 5000M ID 2109:0817 VIA Labs, Inc. I removed some content that is not relevant to my question. Note the Bus 001.Port 006 and Bus 002.Port 006 entries. I verified that both are for the same (one) device. They do not show when I disconnect it. The device is an external 4-port USB3.0 hub. It is listed once as 480M and once as 5000M. Nothing is plugged into any of the four ports. Is this correct? Why does this device show twice in the list? TIA -- Eyal at Home (eyal@xxxxxxxxxxxxxx)