diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index 94d73ec52aba..421479a67da5 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -7494,6 +7494,27 @@ The valid bits in cap.args[0] are:
                                     generate a #UD within the guest.
 =================================== ============================================
 
+7.32 KVM_CAP_MAX_VCPU_ID
+------------------------
+
+:Architectures: x86
+:Target: VM
+:Parameters: args[0] - maximum APIC ID value set for current VM
+:Returns: 0 on success, -EINVAL if args[0] is beyond KVM_MAX_VCPU_IDS
+          supported in KVM or if it has been set.
+
+This capability allows userspace to specify maximum possible APIC ID
+assigned for current VM session prior to the creation of vCPUs, saving
+memory for data structures indexed by the APIC ID.  Userspace is able
+to calculate the limit to APIC ID values from designated
+CPU topology.
+
+The value can be changed only until KVM_ENABLE_CAP is set to a nonzero
+value or until a vCPU is created.  Upon creation of the first vCPU,
+if the value was set to zero or KVM_ENABLE_CAP was not invoked, KVM
+uses the return value of KVM_CHECK_EXTENSION(KVM_CAP_MAX_VCPU_ID) as
+the maximum APIC ID.
+
 8. Other capabilities.
 ======================
 
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 8109805b5429..9dc8d6d0a67d 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1243,6 +1243,12 @@ struct kvm_arch {
 	hpa_t	hv_root_tdp;
 	spinlock_t hv_root_tdp_lock;
 #endif
+	/*
+	 * VM-scope maximum vCPU ID. Used to determine the size of structures
+	 * that increase along with the maximum vCPU ID, in which case, using
+	 * the global KVM_MAX_VCPU_IDS may lead to significant memory waste.
+	 */
+	u32 max_vcpu_ids;
 };
 
 struct kvm_vm_stat {
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 9c2e2b6d1767..25fbb90c7c93 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6087,6 +6087,20 @@ split_irqchip_unlock:
 		}
 		mutex_unlock(&kvm->lock);
 		break;
+	case KVM_CAP_MAX_VCPU_ID:
+		r = -EINVAL;
+		if (cap->args[0] > KVM_MAX_VCPU_IDS)
+			break;
+
+		mutex_lock(&kvm->lock);
+		if (kvm->arch.max_vcpu_ids == cap->args[0]) {
+			r = 0;
+		} else if (!kvm->arch.max_vcpu_ids) {
+			kvm->arch.max_vcpu_ids = cap->args[0];
+			r = 0;
+		}
+		mutex_unlock(&kvm->lock);
+		break;
 	default:
 		r = -EINVAL;
 		break;
@@ -11246,6 +11260,12 @@ int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
 		pr_warn_once("kvm: SMP vm created on host with unstable TSC; "
 			     "guest TSC will not be reliable\n");
 
+	if (!kvm->arch.max_vcpu_ids)
+		kvm->arch.max_vcpu_ids = KVM_MAX_VCPU_IDS;
+
+	if (id >= kvm->arch.max_vcpu_ids)
+		return -EINVAL;
+
 	return 0;
 }