It's interesting how linux kernel dumps work.

You actually have a linux in your linux, and when linux fails, linux takes over and can dump the linux address space so when linux gives up and boots linux, you can use linux to do an autopsy on itself. :)

Or, in other words, you allocate a reserved address space and load a linux#2 kernel in it. When you encounter a panic condition, the system can jump to linux#2 in the reserved address space. It will be non-corrupted and can dump the address space of linux#1 to disk (or a remote system) and reboot.

kexec is the basis for all this, and it can do a lot of other interesting stuff like upgrade in place.