28.11 diagram; para-virtualization layer is below "OS not Virt Aware" when it should be under "Virt

Retalbert

28.11 diagram; para-virtualization layer is below "OS not Virt Aware" when it should be under "Virt Aware OS"

luisviveropena

Hi @Retalbert ,

Why do you think that? We need the paravirtualization layer to communicate with the hardware, and above that layer the paravirtualized guest can exist.

Do you have any reason and/or documentation to demonstrate your statement?

Regards,
Luis.

lee42x

Hello folks,
Thank you for pointing this out.

Yes indeed the para-virtualization guest communicates to the hypervisor via an API, and the API calls must be included in the guest OS.

In full Virtualization, the guest is unaware it is in a virtual environment and issues its regular calls which are intercepted by software or hardware at the hypervisor level for completion.

Where some of the confusion occurs is when we start blending full virtualization and para-virtualization together like using para-virtualized device drivers (disk & network) on a fully virtualized guest with advanced hardware support.

As for the diagram, it is incorrect and will be fixed in the next release.

For additional reading check out:
https://www.unixarena.com/2017/12/para-virtualization-full-virtualization-hardware-assisted-virtualization.html/

Regards Lee