diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index a71d91978d9e..cb31ae071cba 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -8070,6 +8070,23 @@ error/annotated fault.
 
 See KVM_EXIT_MEMORY_FAULT for more information.
 
+7.35 KVM_CAP_X86_APIC_BUS_CYCLES_NS
+-----------------------------------
+
+:Architectures: x86
+:Target: VM
+:Parameters: args[0] is the desired APIC bus clock rate, in nanoseconds
+:Returns: 0 on success, -EINVAL if args[0] contains an invalid value for the
+          frequency or if any vCPUs have been created, -ENXIO if a virtual
+          local APIC has not been created using KVM_CREATE_IRQCHIP.
+
+This capability sets the VM's APIC bus clock frequency, used by KVM's in-kernel
+virtual APIC when emulating APIC timers.  KVM's default value can be retrieved
+by KVM_CHECK_EXTENSION.
+
+Note: Userspace is responsible for correctly configuring CPUID 0x15, a.k.a. the
+core crystal clock frequency, if a non-zero CPUID 0x15 is exposed to the guest.
+
 8. Other capabilities.
 ======================
 
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 9bdc841d5928..09e3460bcbc5 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4706,6 +4706,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 	case KVM_CAP_MEMORY_FAULT_INFO:
 		r = 1;
 		break;
+	case KVM_CAP_X86_APIC_BUS_CYCLES_NS:
+		r = APIC_BUS_CYCLE_NS_DEFAULT;
+		break;
 	case KVM_CAP_EXIT_HYPERCALL:
 		r = KVM_EXIT_HYPERCALL_VALID_MASK;
 		break;
@@ -6746,6 +6749,30 @@ split_irqchip_unlock:
 		}
 		mutex_unlock(&kvm->lock);
 		break;
+	case KVM_CAP_X86_APIC_BUS_CYCLES_NS: {
+		u64 bus_cycle_ns = cap->args[0];
+		u64 unused;
+
+		/*
+		 * Guard against overflow in tmict_to_ns(). 128 is the highest
+		 * divide value that can be programmed in APIC_TDCR.
+		 */
+		r = -EINVAL;
+		if (!bus_cycle_ns ||
+		    check_mul_overflow((u64)U32_MAX * 128, bus_cycle_ns, &unused))
+			break;
+
+		r = 0;
+		mutex_lock(&kvm->lock);
+		if (!irqchip_in_kernel(kvm))
+			r = -ENXIO;
+		else if (kvm->created_vcpus)
+			r = -EINVAL;
+		else
+			kvm->arch.apic_bus_cycle_ns = bus_cycle_ns;
+		mutex_unlock(&kvm->lock);
+		break;
+	}
 	default:
 		r = -EINVAL;
 		break;
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index d03842abae57..ec998e6b6555 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -917,6 +917,7 @@ struct kvm_enable_cap {
 #define KVM_CAP_MEMORY_ATTRIBUTES 233
 #define KVM_CAP_GUEST_MEMFD 234
 #define KVM_CAP_VM_TYPES 235
+#define KVM_CAP_X86_APIC_BUS_CYCLES_NS 236
 
 struct kvm_irq_routing_irqchip {
 	__u32 irqchip;