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TWR-LS1021A: Serial gadget kernel crash is seen randomly

Question asked by Chan Park on Feb 6, 2015

Hi,

 

Test Setup:


   Host (Linux)

   -----------------------------------------

  | Host-Side   Generic USB      USB Host   |

  | Operating | Serial         | Controller |   USB

  | System    | Driver         | Driver     |--------

  | (Linux)   | (usbserial.ko) | and        |        |

  |                              USB Stack  |        |

   -----------------------------------------         |

                                                     |

                                                     |

                                                     |

   Gadget (TWR-LS1021A, USB2 in ULPI mode)           |

   --------------------------------------            |

  | Gadget                   USB Periph. |           |

  | Device-Side |  Gadget  | Controller  |           |

  | Linux       |  Serial  | Driver      |-----------

  | Operating   |  Driver  | and         |

  | System      |(g_serial.| USB Stack   |

  |                  ko)                 |

   --------------------------------------

 

I saw kernel crash once.  It is very hard to reproduce.  The system freezes after the crash.  The full log file is attached.

 

[<80304624>] (_raw_spin_lock_irqsave+0xa/0x34) from [<7f81bbf9>] (gs_put_char+0x16/0x34 [u_serial])

[<7f81bbf9>] (gs_put_char+0x16/0x34 [u_serial]) from [<80185e5f>] (tty_put_char+0x11/0x22)

[<80185e5f>] (tty_put_char+0x11/0x22) from [<80188a03>] (do_output_char+0x109/0x12a)

[<80188a03>] (do_output_char+0x109/0x12a) from [<80188b19>] (__process_echoes+0xf5/0x14e)

[<80188b19>] (__process_echoes+0xf5/0x14e) from [<801891ef>] (commit_echoes+0x37/0x52)

[<801891ef>] (commit_echoes+0x37/0x52) from [<8018a0df>] (__receive_buf+0x2a3/0x504)

[<8018a0df>] (__receive_buf+0x2a3/0x504) from [<8018a383>] (n_tty_receive_buf2+0x43/0x66)

[<8018a383>] (n_tty_receive_buf2+0x43/0x66) from [<8018c215>] (flush_to_ldisc+0x71/0x9a)

[<8018c215>] (flush_to_ldisc+0x71/0x9a) from [<800267b9>] (process_one_work+0x161/0x21c)

[<800267b9>] (process_one_work+0x161/0x21c) from [<80026be9>] (worker_thread+0x179/0x25c)

[<80026be9>] (worker_thread+0x179/0x25c) from [<80029fad>] (kthread+0x5d/0x6c)

[<80029fad>] (kthread+0x5d/0x6c) from [<8000c1f9>] (ret_from_fork+0x11/0x38)

Code: 4603 f3ef 8000 b672 (e853) 1f00

---[ end trace 345734d18d7b1195 ]---

 

Hardware:

TWR-LS1021A REV C2

TWR-SER2

 

Software:

SDK 1.7

Original Attachment has been moved to: LS1021A-g_serial-kernel-crash.txt.zip

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