On Tue, Jan 04, 2022, Paolo Bonzini wrote: > On 12/29/21 02:04, Sean Christopherson wrote: > > > > Speaking of nested, interception of #NM in vmx_update_exception_bitmap() is wrong > > with respect to nested guests. Until XFD is supported for L2, which I didn't see > > in this series, #NM should not be intercepted while L2 is running. > > Why wouldn't L2 support XFD, since there are no new VMCS bits? As long as > L0 knows what to do with XFD and XFD_ERR, it will do the right thing no > matter if L1 or L2 is running. I incorrectly assumed there was something L0 needed to do in order to support nested XFD.