2018-02-21 09:20-0800, Jim Mattson: > On Tue, Feb 20, 2018 at 9:51 PM, KarimAllah Ahmed <karahmed@xxxxxxxxx> wrote: > > > On a related note, which VMentry checks do we decide to do in software > > and which ones we defer to hardware? > > Guest-state checks and some control field checks are currently > deferred to hardware. Some checks simply aren't done at all (like the > ones covered in this patch). > > > The spec has like a dizillion checks that are enfored by hardware on > > VMEntry, which ones do we decide that it makes sense to validate in > > software before-hand? > > We should probably defer only the guest-state checks to hardware. One > problem with the current implementation is that we start loading L2 > vCPU state before VM-entry to vmcs02. If VM-entry to vmcs02 fails > early, with VMfailValid, the vCPU should still contain L1 state > consistent with the VMLAUNCH or VMRESUME instruction and execution > should just fall through to the next L1 instruction. At present, we > have no way of backing out the L2 vCPU state that has already been > loaded. I agree, I'll look into that. Applied the patch and the test, thanks.
