vkernel migration

[Matthew Dillon]

:> A great example is already in DragonFly - process checkpointing. I
:> don't even know how it works as well as it does.
:
:Has this been coupled with the new vkernel mods yet? In other words,
:could I build a checkpointable kernel and then pause it, put it away
:for a month, and come back to it? ( Pardon me if I'm sounding naive
:here. :) )
:------
:Dave Hayes - Consultant - Altadena CA, USA - dave at jetcafe.org 
:>>> The opinions expressed above are entirely my own <<<

    It won't work, but it would not be hard to save and restore the state:

    * The checkpointing code doesn't understand VPAGETABLE
      mappings.   Offset and page directory settings would have to be
      saved and restored.

    * Network (TAP) interface code would have to reopen the interface and
      re-set its parameters.

    * Console driver would have to restore the console mode via termios.

    * Kernel core would have to re-create the VM spaces for the various 
      processes on checkpoint restore (but otherwise would not have to do
      anything fancy, since the VM spaces are controlled entirely by 
      VPAGETABLE mappings).

					-Matt
					Matthew Dillon 
					<dillon at backplane.com>