Everyone, thank you for your attention and suggestions. Johan, perfect, thank you, that did indeed help and has fixed the issue I was seeing. The change replaced dev_err() with dev_dbg() -- thus not logging (by default) what was a very noisy flood of messages. Does that simply change timing enough such that the USB HCD has time to process the disconnect? Or is there something else going on that I'm missing? Thank you, ~Mark > -----Original Message----- > From: Johan Hovold [mailto:jhovold@xxxxxxxxx] On Behalf Of Johan Hovold > Sent: Tuesday, April 07, 2015 2:58 PM > To: Mark Enstone > Cc: linux-usb@xxxxxxxxxxxxxxx > Subject: Re: Question: drivers/usb/serial/generic.c: > usb_serial_generic_read_bulk_callback() > <deletia> > > Question: have you seen such behavior? > > Yes, I just debugged a related issue where using large unaligned buffers could > prevent the hub driver from processing the disconnect event. This could also be > triggered by enabling debugging, which would print the -EPROTO error message > to my slow serial console. > > I just realised that this debug message used to be an error before 3.19, and > could therefore trigger the bug you're experiencing on systems with a slow > console. > > Could you try updating to 3.19 (or later) or to cherry pick aa8e22128b40 > ("usb: serial: silence all non-critical read errors") and see if that helps? > > We should backport that one to stable either way. > > Thanks, > Johan -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
