Radim Krčmář <rkrcmar@xxxxxxxxxx> writes: > 2017-07-11 14:35-0400, Bandan Das: >> Jim Mattson <jmattson@xxxxxxxxxx> writes: >> ... >> >>> I can find the definition for an vmexit in case of index >= >> >>> VMFUNC_EPTP_ENTRIES, but not for !vmcs12->eptp_list_address in the SDM. >> >>> >> >>> Can you give me a hint? >> >> >> >> I don't think there is. Since, we are basically emulating eptp switching >> >> for L2, this is a good check to have. >> > >> > There is nothing wrong with a hypervisor using physical page 0 for >> > whatever purpose it likes, including an EPTP list. >> >> Right, but of all the things, a l1 hypervisor wanting page 0 for a eptp list >> address most likely means it forgot to initialize it. Whatever damage it does will >> still end up with vmfunc vmexit anyway. > > Most likely, but not certainly. I also don't see a to diverge from the > spec here. Actually, this is a specific case where I would like to diverge from the spec. But then again, it's L1 shooting itself in the foot and this would be a rarely used code path, so, I am fine removing it.
