Our product is designed by referencing SABRESDB with IMX6Q. The linux kernel version is 3.14.28. We use watchdog by "open("/dev/watchdog", O_WRONLY);" and the timeout of watchdog is 15 second. We feed the watchdog and print one information from debug uart COM every second in our application program . Usually, the watchdog works well. But after about 10 day, the watchdog reset without any error information. What`s more, the time between the last feeding watchdog information and the first kernel debug information is difference, sometimes it is 2 minute, sometimes is 8 minute, sometimes is more than 30 minute.
It is impossible that it last more than 30 minute before the watchdog reset the system supposing that our application program do not feed the watchdog. Can someone give us some advise about this issue or how to debug the issue? Thanks in advance!