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It is running at EL1/0 when EL2 is present that is >>>>> interesting, and I see no coverage on that front. >>>> >>>> Sorry, I did not get this comment fully. >>>> When we run selftest on Host with -g option, the guest code will run in vEL2 as L1. >>>> This is implemented as per comment in V1. >>>> >>>> When we run same selftest from L1 shell, then guest_code will be running in EL0/1 like running from L0. >>> >>> What good does this bring us if we need to boot a full guest OS to run >>> tests? What we need is synthetic tests that implement the whole stack: >>> >>> - L1 guest hypervisor >>> - L2 guest hypervisor >>> - L2 guest >>> - L3 guest hypervisor >>> - L3 guest >>> - [...] >> >> IIUC, selftest leverages host OS support and uses various IOCTLs to >> support the guest_code run. Are you saying to implement all this >> again (without OS help) in guest_code to run it as hypervisor and >> launch guest_code2 as NestedVM?. > > The whole point of having small selftests is to run something that is > simpler several orders of magnitude simpler than the full blown > OS/hypervisor. So indeed, I'm asking for selftests that build chains > of guests up to some level and verify that the nesting, as described > in the architecture, works correctly. > Do you see value in the patches as they are, without the changes to support the bare-metal hypervisor in guest, or will you only consider them if they are first reworked to support the recursive guests? -- Thanks, Gk