On 15/02/2017 23:00, Jim Mattson wrote: > Yes, I see that this works for the in-kernel instruction emulator. My > question was regarding a hypothetical user-space instruction emulator. I > can see how a #PF resulting from KVM_TRANSLATE could be injected with > KVM_SET_VCPU_EVENTS (if KVM_TRANSLATE was forthcoming with the error code, > anyway). However, what if the KVM_TRANSLATE ioctl were to fail because of > an EPT violation? I don't see an ioctl that would allow userspace to inject > a VM-exit event (complete with exit reason, exit qualification, and all of > the other VM-exit information fields that might be relevant.) Or are you > saying that simply encountering the EPT violation while > trying to answer a KVM_TRANSLATE request would induce the VM-exit? I think it should, yes. There are other limitations of KVM_TRANSLATE (it always assumes CPL=0 for example) but the same logic would apply to KVM_TRANSLATE and to the in-kernel emulator. Paolo >> One thing where we're lacking a bit is that translate_nested_gpa should >> have an argument for "translating translated guest address" vs. >> "translating guest page structure address", in order to set EXITINFO or >> exit qualification correctly. This is incorrect right now. >> >> Paolo >
