Our device went for reset. So it starts loading and unloading the serial USB port. Here the serious concern is kernel lock. Once it happens the system is unusable and hard reboot is the only way of recovering it.
Kernel version is 3.12.0 Regards, Saravanan N On Wed, Dec 9, 2015 at 2:21 PM, Greg KH <gre...@linuxfoundation.org> wrote: > On Wed, Dec 09, 2015 at 12:36:12PM -0600, SaRaVanAn wrote: >> We are using sierra modem for 4G LTE networks. we used to communicate >> with modem using AT commands via ttyUSB ports. >> Recently we observed a crash in usb driver interface when we try to >> post some AT commands. After the crash the kernel seems to be hanged. >> We were not able to execute any commands or open a new tty terminal. >> Even reboot command was not working fine. >> The system went to completely unusable/unstable state. It recovered >> only after hard reboot. >> >> >> >> Nov 30 18:59:01 ATCMD = [AT+CMEE=2] >> Nov 30 18:59:02 [AT_TRX]Garbage cleared >> Nov 30 18:59:02 [AT_TRX]Data from Stream --> [OK] >> Nov 30 18:59:02 [AT_TRX]Poll Ended >> Nov 30 18:59:02 [AT_TRX]Result :[-1] >> >> Nov 30 18:59:02 [AT_TRX]Garbage cleared >> Nov 30 18:59:02 kernel: [19926.147811] usb 2-1.3: USB disconnect, >> device number 126 > > Your device disconnected itself from the system for some reason, you > might want to look into why that happens, could be an electrical issue. > >> Nov 30 18:59:02 kernel: [19926.147985] sierra ttyUSB0: Sierra USB >> modem converter now disconnected from ttyUSB0 >> Nov 30 18:59:02 kernel: [19926.148002] sierra 2-1.3:1.0: device disconnected >> Nov 30 18:59:02 kernel: [19926.148127] sierra ttyUSB1: Sierra USB >> modem converter now disconnected from ttyUSB1 >> Nov 30 18:59:02 kernel: [19926.148138] sierra 2-1.3:1.1: device disconnected >> Nov 30 18:59:02 kernel: [19926.150070] sierra ttyUSB2: >> sierra_submit_rx_urbs: submit urb failed: -19 >> Nov 30 18:59:02 kernel: [19926.152626] sierra ttyUSB2: >> sierra_submit_rx_urbs: submit urb failed: -19 >> Nov 30 18:59:02 kernel: [19926.155136] sierra ttyUSB2: >> sierra_submit_rx_urbs: submit urb failed: -19 >> Nov 30 18:59:02 kernel: [19926.157589] sierra ttyUSB2: >> sierra_submit_rx_urbs: submit urb failed: -19 >> Nov 30 18:59:02 kernel: [19926.159999] sierra ttyUSB2: >> sierra_submit_rx_urbs: submit urb failed: -19 >> Nov 30 18:59:02 kernel: [19926.162438] sierra ttyUSB2: >> sierra_submit_rx_urbs: submit urb failed: -19 >> Nov 30 18:59:02 kernel: [19926.164870] sierra ttyUSB2: >> sierra_submit_rx_urbs: submit urb failed: -19 >> Nov 30 19:01:12 kernel: [20056.174514] INFO: task khubd:369 blocked >> for more than 120 seconds. > > Not good, what kernel version is this? > > thanks, > > greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
