On Wed, 22 Feb 2006, Thomas Thanner wrote: > Thank you for analyzing the log. > > We bought some new CF cards and initially it worked well. We thought the > problem is solved now. But unfortunately the error occures again. > > When we do the testing with large files containing only zeroes, then we have > no problems. But as soon as we try to copy real data we get siminal errors > again.
That certainly indicates a hardware problem of some sort. The software doesn't care what values are in the data stream. It doesn't even look at the data stream! > Now we wanted to generate the log files as required and magically no more > errors occure! What shall we do in this case? That's a bad situation. If you want, I could send you a patch to log only the error codes and nothing else. It probably wouldn't help, though, since the codes would be the same as what we've already seen. > These errors are really nasty, when it occures while copying large files > (>2GByte) the servers cannot be shut down any more, because the copy process > cannot be terminated. We waited for about 2 days, but no end was in sight! Unplugging the USB cable should terminate the copy process. But there's a combination of hardware and software problems that cause the EHCI driver to hang on some systems under certain circumstances. > Interestingly we have same error no matter whether we use "ub" or > "usb-storage" modules for access (using different kernels). That's because this is a hardware problem, not a software problem. > All works fine, when we unload EHCI and use only USB1.1 over UHCI. But in > this > case all our USB ports get USB 1.1 and that is not good. Is there a > possibiliy > to force some ports to USB1.1 and let the others on USB2.0? don't think so, > but it might be a nice feature, to solve our problem :-) Like I told you before: Get a USB 1.1 hub and attach it to the computer. Any devices you plug into the hub will automatically run at full speed instead of high speed. > We have also tests on different servers of same kind and of completely other > machines. The error remains the same. > > We have tested four different CF-cards, all the same error. > > We are more than willing to take part in USB stack debugging and hacking, but > we might need some hints where we can start to look for our problem. At the > moment we have only experiences in hacking xfree and xorg servers. It sounds like you should start looking at the EHCI driver: drivers/usb/host/ehci*. I doubt you'll find anything wrong, but go ahead and look. A better approach might be to buy an add-on PCI USB controller card. There's a good chance it would work better than the USB controller on your motherboard. Alan Stern ------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Do you grep through log files for problems? Stop! Download the new AJAX search engine that makes searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=103432&bid=230486&dat=121642 _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-users
