quoted

+	/*
+	 * If the TD isn't finalized/runnable, then userspace is initializing
+	 * the VM image via KVM_TDX_INIT_MEM_REGION.  Increment the number of
+	 * pages that need to be mapped and initialized via TDH.MEM.PAGE.ADD.
+	 * KVM_TDX_FINALIZE_VM checks the counter to ensure all mapped pages
+	 * have been added to the image, to prevent running the TD with a
+	 * valid mapping in the mirror EPT, but not in the S-EPT.
+	 */
+	if (unlikely(kvm_tdx->state != TD_STATE_RUNNABLE)) {
+		if (KVM_BUG_ON(kvm->arch.pre_fault_allowed, kvm))
+			return -EIO;
+
+		atomic64_inc(&kvm_tdx->nr_premapped);

Nit: the comment

  /* nr_premapped will be decreased when tdh_mem_page_add() is called. */

is lost.  I think we can somehow embed it to the big comment above?

Please ignore this.  I saw the whole 'nr_premapped' eventually got removed
later in this series so don't bother :-)