I'm running lsusb several times, but it's taking a long time to return.Is there a reason why it won't finish or that it runs slowly?I've tried killing their PIDs but that doesn't work. So I close the gnome terminal tab where one is running, and its tty becomes ?:$ ps aux | grep -i lsusbt        13845  0.0  0.0  40000  3788 pts/21   D    14:59   0:00 lsusbt        14216  0.0  0.0  40000  3812 pts/21   D+   15:06   0:00 lsusbt        14236  0.0  0.0  40000  3792 ?        D    15:06   0:00 lsusbIf I am correct, D means the process is being killed?  Why is it still hanging?dmesg kept saying[384722.320066] unregister_netdevice: waiting for wlan1 to become free. Usage count = 1 (repeated 77 times)If it helps, my internal wireless network adapter doesn't work, so I plug in an external one (which doesn't work either).
Why is lsusb taking so long?
usb