On Tue, 17 Jul 2012, Sarah Sharp wrote: > > See > > > > http://marc.info/?l=linux-usb&m=134236551409964&w=2 > > > > Apparently the ASM1042 reports that a transfer completed normally even > > when it was short (or when it was cancelled). > > When an URB is canceled, the xHCI driver asks the endpoint ring to be > stopped. However, the transfer may be completed before the ring stops, > so we can have a canceled transfer where the full buffer really was > transferred. I don't see that as a bug, it's just a race condition that > drivers need to deal with.
The events in the email message mentioned above did not involve a race. It's clear that no data got transferred at all, and yet usbmon reported actual_length equal to transfer_buffer_length when the tranfer was cancelled. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
