diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index d542bd99a9a416c02d2af232026223dffbfa2294..19438a5c942b64b9d157deff213998b243e54846 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -6220,6 +6220,27 @@ default.
 
 See Documentation/x86/sgx.rst for more details.
 
+7.23 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_ID
+          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 6ecc24e335ffa7392c8d52a8a9a8fbcaced10858..1b08ba66c088fa79a6a6615ba19f5c3133e2311b 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1017,6 +1017,12 @@ struct kvm_arch {
 	struct list_head tdp_mmu_roots;
 	/* List of struct tdp_mmu_pages not being used as roots */
 	struct list_head tdp_mmu_pages;
+	/*
+	 * 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_ID 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 c0d397fcf049d0a0eaf3037fd880ea66612804d7..bee4c895276ef072796223c9a569484dcdf16491 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5304,6 +5304,20 @@ int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
 		break;
 	}
 #endif
+	case KVM_CAP_MAX_VCPU_ID:
+		r = -EINVAL;
+		if (cap->args[0] > KVM_MAX_VCPU_ID)
+			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;
@@ -9929,6 +9943,12 @@ 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_ID;
+
+	if (id >= kvm->arch.max_vcpu_ids)
+		return -EINVAL;
+
 	return 0;
 }