On 11 Oct 2014, Paul Martin spake thusly: > Having been privy to the firmware of the eKey, it is very simplisting, > with no implementation whatsoever of any flow control.
That's what I thought. (Why would something that just provides data at a constant rate way below that of even the slowest USB bus *need* flow control?) One presumes therefore that the kernel suddenly trying to do flow control on shutdown would fubar the firmware's internal state, leading to the symptoms I see. So, the question becomes, is there a way to spot this general 'no flow control on this device' thing from the kernel side, or do we need a blacklist? Or, perhaps, if this is commonplace for cdc-acm devices, a whitelist? I can't imagine it's *that* commonplace or someone would have spotted this already in the months and months it took me to do the bisection. Maybe all non-modem cdc-acm devices should eschew flow control, or something? (This is a genuine guess and is almost certainly wrong.) -- NULL && (void) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/