On Thu, 30 Jul 2009, Matthijs Kooijman wrote: > Hi Alan, > > > > Another thing I was seeing just now, is XactErrs when nothing is plugged into > > > the (possibly faulty) hub. Interestingly enough, the retry counts there were > > > negative, starting with -223. Looking at the code, I'm not so sure if this is > > > supposed to happen. It seems that the qh->xacterrs variable is somehow large > > > (255, since the retry count is 32 - xacterrs). This smells like an overflow, > > > which probably shouldn't happen. > > > > It certainly shouldn't. Can you provide the dmesg log? > > I've put up the log from yesterday at > http://www.stdout.nl/ehci-debug/xacterr-overflow.txt > > I don't have the USB hub here right now to do more testing, but perhaps this > log is enough? Wow. The only thing I can think of which might cause this is if you didn't apply the new patch correctly. In particular, it looks like you managed to erase the line saying qh->xacterrs = QH_XACTERR_MAX; from qh_link_async() in ehci-q.c. It's not _too_ unlikely; that line immediately follows one of the changes in the patch. This isn't exactly an overflow. It's more like qh->xacterrs was left equal to 0 instead of being initialized to 32. That line does the initialization -- hence my suspicion. Alan Stern -- 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
