NOVA, NUL, snapshotting

Sartakov A. Vasily sartakov at
Wed Oct 2 19:20:45 CEST 2013

>>> Is that enough? What should I do with mappings (NPT in particular
>>> caused me questions), devices?
>> ... you need to save and restore device state. Jacek Galowicz has
>> implemented this already. For a short overview of what he did check:
> I understand that issue. But I do not understand how multiboot/vbios part works. Can you explain me what happens from 
> handle_cpu_init ( to main function (or __start ) of munich. I.e. in range from message "reset CPU state" and first console message of Munich. 
> I do not need full detailed description, just main idea. 
> I stuck on very early stage of VM booting. I see intensive messaging of VBios, Lapic, RTC, Serial, I have got several traps (I count svm_invalid trap), but I seriously do not see the reason, the code that trigger traps. 

I'm wrong. 

>> I understand the VMM-specific code will be published at some point.
>>> What is the cpu state in receive function of vbios_multiboot? Is it
>>> a beginning state of VM, when the Munech is uploaded?
>> This function is called whenever some code issues int 19h to (re)start
>> the BIOS boot procedure. Initially this is called by the vBIOS itself.
>> I am not sure what you mean with your second question.

Sartakov A. Vasily
sartakov at

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