Hi, I have three, 4-port USB-to-Serial adapters connected to a Linux system running kernel 3.3.7-1. These three adapters are connected to the system via a USB hub. The application is a DOS app (point of sale system), running in DOSEMU (DOS emulator), that connects directly to these serial devices. This logs below coincide with a lock-up of the production application. We are using software flow control at 38400 baud, we are not using hardware flow control. Sep 8 13:44:54 prod05 kernel: [25716.429799] ftdi_sio ttyUSB11: urb failed to clear flow control Sep 8 13:46:15 prod05 kernel: [25797.281701] ftdi_sio ttyUSB11: ftdi_set_termios FAILED to set databits/stopbits/parity Sep 8 13:46:16 prod05 kernel: [25798.279805] ftdi_sio ttyUSB11: ftdi_set_termios urb failed to set baudrate Sep 8 13:46:21 prod05 kernel: [25803.270534] ftdi_sio ttyUSB11: urb failed to clear flow control More of these messages are repeated for all the serial ports connected to the 3rd adapter (see below). Here is the exact model I'm using. And again, 3 of these connected to a USB hub. http://www.amazon.com/dp/B004EKI4DC/ref=pe_175190_21431760_M2T1_SC_3p_dp_1 > This PRO Grade Adapter is build around FT4232H from FTDI Semiconductors which is the best and most reliable Quad Serial to USB processors on the market it also uses ZT232E RS232 transciever from ZyWyn USA. USB cable is 6ft Total Lenght with Port Identificaiton marks on each of the DB9 Male ends. It's worth noting that this setup is not a one-off. I have two production installations of the same size (12 serial ports) and this is the first I've seen of the issue. The two installations may have different model hubs. Lastly, the installation (prod05) that succumbed to this error was running perfectly for 3 days under load - but this Saturday afternoon was the peak of their business and it failed. Bummer. Does anyone know how to prevent this from happening? Caylan Additional errors on ttyUSB8,9,10,11 only: > Sep 8 13:44:54 prod05 kernel: [25716.429799] ftdi_sio ttyUSB11: urb failed to clear flow control > Sep 8 13:46:15 prod05 kernel: [25797.281701] ftdi_sio ttyUSB11: ftdi_set_termios FAILED to set databits/stopbits/parity > Sep 8 13:46:16 prod05 kernel: [25798.279805] ftdi_sio ttyUSB11: ftdi_set_termios urb failed to set baudrate > Sep 8 13:46:21 prod05 kernel: [25803.270534] ftdi_sio ttyUSB11: urb failed to clear flow control > Sep 8 13:49:02 prod05 kernel: [25964.004184] ftdi_sio ttyUSB8: ftdi_set_termios urb failed to set baudrate > Sep 8 13:49:07 prod05 kernel: [25968.994768] ftdi_sio ttyUSB8: urb failed to clear flow control > Sep 8 13:49:12 prod05 kernel: [25973.985461] ftdi_sio ttyUSB8: urb failed to clear flow control > Sep 8 13:49:17 prod05 kernel: [25978.976051] ftdi_sio ttyUSB8: error from flowcontrol urb > Sep 8 13:49:23 prod05 kernel: [25984.964723] ftdi_sio ttyUSB9: ftdi_set_termios urb failed to set baudrate > Sep 8 13:49:28 prod05 kernel: [25989.955322] ftdi_sio ttyUSB9: urb failed to clear flow control > Sep 8 13:49:33 prod05 kernel: [25994.945924] ftdi_sio ttyUSB9: urb failed to clear flow control > Sep 8 13:49:38 prod05 kernel: [25999.936628] ftdi_sio ttyUSB9: error from flowcontrol urb > Sep 8 13:49:44 prod05 kernel: [26005.925307] ftdi_sio ttyUSB10: ftdi_set_termios urb failed to set baudrate > Sep 8 13:49:49 prod05 kernel: [26010.915876] ftdi_sio ttyUSB10: urb failed to clear flow control > Sep 8 13:49:54 prod05 kernel: [26015.907611] ftdi_sio ttyUSB10: urb failed to clear flow control > Sep 8 13:49:59 prod05 kernel: [26020.898192] ftdi_sio ttyUSB10: error from flowcontrol urb > Sep 8 13:50:05 prod05 kernel: [26026.887885] ftdi_sio ttyUSB11: ftdi_set_termios urb failed to set baudrate > Sep 8 13:50:10 prod05 kernel: [26031.878474] ftdi_sio ttyUSB11: urb failed to clear flow control > Sep 8 13:50:15 prod05 kernel: [26036.869139] ftdi_sio ttyUSB11: urb failed to clear flow control > Sep 8 13:50:20 prod05 kernel: [26041.859745] ftdi_sio ttyUSB11: error from flowcontrol urb > Sep 8 13:49:26 prod05 kernel: [26064.438521] ftdi_sio ttyUSB8: ftdi_set_termios FAILED to set databits/stopbits/parity > Sep 8 13:49:27 prod05 kernel: [26065.436636] ftdi_sio ttyUSB8: ftdi_set_termios urb failed to set baudrate > Sep 8 13:49:37 prod05 kernel: [26075.417924] ftdi_sio ttyUSB8: urb failed to clear flow control > Sep 8 13:49:47 prod05 kernel: [26085.399337] ftdi_sio ttyUSB8: urb failed to clear flow control > Sep 8 13:49:52 prod05 kernel: [26090.389917] ftdi_sio ttyUSB8: error from flowcontrol urb > Sep 8 13:50:03 prod05 kernel: [26101.447300] ftdi_sio ttyUSB9: ftdi_set_termios FAILED to set databits/stopbits/parity > Sep 8 13:50:04 prod05 kernel: [26102.445540] ftdi_sio ttyUSB9: ftdi_set_termios urb failed to set baudrate > Sep 8 13:50:14 prod05 kernel: [26112.426702] ftdi_sio ttyUSB9: urb failed to clear flow control > Sep 8 13:50:24 prod05 kernel: [26122.408004] ftdi_sio ttyUSB9: urb failed to clear flow control > Sep 8 13:50:29 prod05 kernel: [26127.398696] ftdi_sio ttyUSB9: error from flowcontrol urb > Sep 8 13:50:40 prod05 kernel: [26138.387209] ftdi_sio ttyUSB10: ftdi_set_termios FAILED to set databits/stopbits/parity > Sep 8 13:50:41 prod05 kernel: [26139.385324] ftdi_sio ttyUSB10: ftdi_set_termios urb failed to set baudrate > Sep 8 13:50:51 prod05 kernel: [26149.366611] ftdi_sio ttyUSB10: urb failed to clear flow control > Sep 8 13:51:01 prod05 kernel: [26159.347903] ftdi_sio ttyUSB10: urb failed to clear flow control > Sep 8 13:51:06 prod05 kernel: [26164.338605] ftdi_sio ttyUSB10: error from flowcontrol urb > Sep 8 13:51:17 prod05 kernel: [26175.324994] ftdi_sio ttyUSB11: ftdi_set_termios FAILED to set databits/stopbits/parity > Sep 8 13:51:18 prod05 kernel: [26176.323237] ftdi_sio ttyUSB11: ftdi_set_termios urb failed to set baudrate > Sep 8 13:51:28 prod05 kernel: [26186.304524] ftdi_sio ttyUSB11: urb failed to clear flow control > Sep 8 13:51:38 prod05 kernel: [26196.285812] ftdi_sio ttyUSB11: urb failed to clear flow control > Sep 8 13:51:43 prod05 kernel: [26201.276525] ftdi_sio ttyUSB11: error from flowcontrol urb > Sep 8 13:51:55 prod05 kernel: [26214.065499] ftdi_sio ttyUSB8: ftdi_set_termios FAILED to set databits/stopbits/parity > Sep 8 13:51:56 prod05 kernel: [26215.063620] ftdi_sio ttyUSB8: ftdi_set_termios urb failed to set baudrate > Sep 8 13:52:06 prod05 kernel: [26225.045014] ftdi_sio ttyUSB8: urb failed to clear flow control > Sep 8 13:52:12 prod05 kernel: [26231.033836] ftdi_sio ttyUSB8: ftdi_set_termios FAILED to set databits/stopbits/parity > Sep 8 13:52:17 prod05 kernel: [26236.024420] ftdi_sio ttyUSB8: ftdi_set_termios error from disable flowcontrol urb > Sep 8 13:52:27 prod05 kernel: [26246.005825] ftdi_sio ttyUSB8: urb failed to clear flow control > Sep 8 13:52:28 prod05 kernel: [26247.003941] ftdi_sio ttyUSB8: ftdi_set_termios FAILED to set databits/stopbits/parity > Sep 8 13:52:29 prod05 kernel: [26248.002072] ftdi_sio ttyUSB8: ftdi_set_termios urb failed to set baudrate > Sep 8 13:52:39 prod05 kernel: [26257.983338] ftdi_sio ttyUSB8: urb failed to clear flow control > Sep 8 13:52:50 prod05 kernel: [26268.962756] ftdi_sio ttyUSB8: ftdi_set_termios FAILED to set databits/stopbits/parity > Sep 8 13:52:51 prod05 kernel: [26269.960877] ftdi_sio ttyUSB8: ftdi_set_termios urb failed to set baudrate > Sep 8 13:52:56 prod05 kernel: [26274.951579] ftdi_sio ttyUSB8: urb failed to clear flow control > Sep 8 13:54:32 prod05 kernel: [26370.799330] ftdi_sio ttyUSB8: ftdi_set_termios FAILED to set databits/stopbits/parity > Sep 8 13:54:33 prod05 kernel: [26371.797430] ftdi_sio ttyUSB8: ftdi_set_termios urb failed to set baudrate > Sep 8 13:54:38 prod05 kernel: [26376.788037] ftdi_sio ttyUSB8: urb failed to clear flow control > Sep 8 13:54:43 prod05 kernel: [26381.778735] ftdi_sio ttyUSB8: urb failed to clear flow control > Sep 8 13:54:48 prod05 kernel: [26386.769421] ftdi_sio ttyUSB8: error from flowcontrol urb > Sep 8 13:55:13 prod05 kernel: [26410.823294] ftdi_sio ttyUSB8: ftdi_set_termios FAILED to set databits/stopbits/parity > Sep 8 13:55:14 prod05 kernel: [26411.821410] ftdi_sio ttyUSB8: ftdi_set_termios urb failed to set baudrate > Sep 8 13:55:24 prod05 kernel: [26421.802823] ftdi_sio ttyUSB8: urb failed to clear flow control > Sep 8 13:55:34 prod05 kernel: [26431.784110] ftdi_sio ttyUSB8: urb failed to clear flow control > Sep 8 13:55:39 prod05 kernel: [26436.774700] ftdi_sio ttyUSB8: error from flowcontrol urb > Sep 8 13:55:50 prod05 kernel: [26447.830078] ftdi_sio ttyUSB9: ftdi_set_termios FAILED to set databits/stopbits/parity > Sep 8 13:55:51 prod05 kernel: [26448.828192] ftdi_sio ttyUSB9: ftdi_set_termios urb failed to set baudrate > Sep 8 13:56:01 prod05 kernel: [26458.809483] ftdi_sio ttyUSB9: urb failed to clear flow control > Sep 8 13:56:11 prod05 kernel: [26468.795890] ftdi_sio ttyUSB9: urb failed to clear flow control > Sep 8 13:56:16 prod05 kernel: [26473.786445] ftdi_sio ttyUSB9: error from flowcontrol urb > Sep 8 13:56:27 prod05 kernel: [26484.770984] ftdi_sio ttyUSB10: ftdi_set_termios FAILED to set databits/stopbits/parity > Sep 8 13:56:28 prod05 kernel: [26485.769100] ftdi_sio ttyUSB10: ftdi_set_termios urb failed to set baudrate > Sep 8 13:56:38 prod05 kernel: [26495.750387] ftdi_sio ttyUSB10: urb failed to clear flow control > Sep 8 13:56:48 prod05 kernel: [26505.731814] ftdi_sio ttyUSB10: urb failed to clear flow control > Sep 8 13:56:53 prod05 kernel: [26510.722389] ftdi_sio ttyUSB10: error from flowcontrol urb > Sep 8 13:57:04 prod05 kernel: [26521.710771] ftdi_sio ttyUSB11: ftdi_set_termios FAILED to set databits/stopbits/parity > Sep 8 13:57:05 prod05 kernel: [26522.709008] ftdi_sio ttyUSB11: ftdi_set_termios urb failed to set baudrate > Sep 8 13:57:15 prod05 kernel: [26532.690296] ftdi_sio ttyUSB11: urb failed to clear flow control > Sep 8 13:57:25 prod05 kernel: [26542.672594] ftdi_sio ttyUSB11: urb failed to clear flow control > Sep 8 13:57:30 prod05 kernel: [26547.663288] ftdi_sio ttyUSB11: error from flowcontrol urb > Sep 8 13:57:42 prod05 kernel: [26560.443286] ftdi_sio ttyUSB8: ftdi_set_termios FAILED to set databits/stopbits/parity > Sep 8 13:57:43 prod05 kernel: [26561.441658] ftdi_sio ttyUSB8: ftdi_set_termios urb failed to set baudrate > Sep 8 13:57:53 prod05 kernel: [26571.422797] ftdi_sio ttyUSB8: urb failed to clear flow control > Sep 8 13:57:59 prod05 kernel: [26577.411643] ftdi_sio ttyUSB8: ftdi_set_termios FAILED to set databits/stopbits/parity > Sep 8 13:58:04 prod05 kernel: [26582.403202] ftdi_sio ttyUSB8: ftdi_set_termios error from disable flowcontrol urb > Sep 8 13:58:14 prod05 kernel: [26592.384505] ftdi_sio ttyUSB8: urb failed to clear flow control > Sep 8 13:58:15 prod05 kernel: [26593.389740] ftdi_sio ttyUSB8: ftdi_set_termios FAILED to set databits/stopbits/parity > Sep 8 13:58:16 prod05 kernel: [26594.387837] ftdi_sio ttyUSB8: ftdi_set_termios urb failed to set baudrate > Sep 8 13:58:26 prod05 kernel: [26604.369130] ftdi_sio ttyUSB8: urb failed to clear flow control > Sep 8 13:58:31 prod05 kernel: [26609.359850] ftdi_sio ttyUSB8: urb failed to clear flow control > Sep 8 13:58:36 prod05 kernel: [26614.350560] ftdi_sio ttyUSB8: error from flowcontrol urb -- 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
