title: How to detect a kernel panic after reboot
body: <p>I have some unexpected reboot on a embedded device. I am currently able to detect a hardware watchdog issue thanks to an ioctl call. Now I would like be able to detect if a kernel panic was the reason for a reboot. I find some articles concerning crashkernel and crashdump but I was not able to make it work properly. And I dont want to store the kernel panic log. Just be able to know if kernel panic happens.</p>
  
  <p>My current idea was to write in a reserved space on mmc. I am currently using a reserved space to handle a double distribution system. It is a good idea ? Is it possible to write in mmc during a kernel panic ? I am not sure but its seems that I can use kind of kernel panic hook to run routine on this event.</p>
  
  <p>There is no standard way to be able to check that kernel panic happened on boot ?</p>