On Tue, Jul 21, 2009 at 05:16:25PM +0100, Alan Cox wrote: > > I got something similar with a pl2303 device, though not a crash. I > > plugged in the device, opened /dev/ttyUSB0, unplugged the device, then > > tried to read from the open file descriptor. The read provoked this: > > That looks like it occurs after the read, however that trace shows the > close() method being called off sys_close() which in turn means a hang up > didn't occur when it was unplugged. It was, at least in my case. Did some printk debugging and it showed that the hangup callback was entered what freed the serial device. > > This is only a lockdep warning, and I don't understand its > > significance. Even worse, when I plugged in a USB flash drive > > afterward this appeared: > > Looks like something freed the resources but didn't hang up when the > disconnect occurred Probably the real fix would be to let the tty layer know the device died from the hangup handler. -- 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
