On 8 Mar 2010 19:01:50 +0100 Marcel Winandy (MW) wrote:
MW> just out of curiosity: assuming I run a Linux VM on top of NOVA. NOVA MW> runs obviously in ring 0. In which protection ring of the CPU will the MW> Linux kernel be executed? Ring 1 or together with the userland apps in MW> ring 3?
Neither in ring 1 nor in ring 3.
A CPU that supports VMX or SVM provides 4 host rings and 4 guest rings. They are used as follows: host/ring0=NOVA microhypervisor, host/ring3=NOVA user-level environment, guest/ring0=Linux kernel, guest/ring3=Linux apps.
Cheers,
- Udo