I believe we should also have a handler for .msr_filter_changed. Without an .msr_filter_changed handler, a host crash can occur if we first set up a vcpu for the TD, and then set an MSR filter. If we first set up a vcpu for the TD, and then set an MSR filter, upon vcpu_enter_guest, the .msr_filter_changed handler (currently vmx_msr_filter_changed()) will be invoked. to_vmx(vcpu) interprets the containing struct of struct kvm_vcpu to be a struct vcpu_vmx instead of a struct vcpu_tdx. In my case, I was working on a selftest and the missing handler caused a NULL dereference in vmx_disable_intercept_for_msr() because vmx->vmcs01.msr_bitmap is NULL.
