On Wed, Jan 23, 2019 at 08:50:38PM +0000, Måns Rullgård wrote: > Bin Liu <b-liu@xxxxxx> writes: > > >> > > Why doesn't the same problem occur with other types of host controller? > >> > > >> > Not sure, I am on musb for most of the times. Maybe other HCD doesn't > >> > giveback URBs with -EPROTO in such error case. > >> > >> ehci-hcd also uses -EPROTO. > > > > Is it possible to test the use case on ehci? > > > > - connect a multi-ports usb serial device to a hub; > > - open multiple ports with cat command; > > - remove the usb serial device from the hub; > > - console lockup happens? > > It doesn't seem to happen using ehci or even musb on Allwinner A20. > I have only seen the problem with musb on AM3358. The A20 being dual core may possible explain the difference. Johan
