diff --git a/target/arm/kvm.c b/target/arm/kvm.c
index b10581fa06..b473c63edb 100644
--- a/target/arm/kvm.c
+++ b/target/arm/kvm.c
@@ -182,6 +182,7 @@ int kvm_arm_get_max_vm_ipa_size(MachineState *ms)
 
 int kvm_arch_init(MachineState *ms, KVMState *s)
 {
+    int ret = 0;
     /* For ARM interrupt delivery is always asynchronous,
      * whether we are using an in-kernel VGIC or not.
      */
@@ -195,7 +196,14 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
 
     cap_has_mp_state = kvm_check_extension(s, KVM_CAP_MP_STATE);
 
-    return 0;
+    if (ms->smp.cpus > 256 &&
+        !kvm_check_extension(s, KVM_CAP_ARM_IRQ_LINE_LAYOUT_2)) {
+        error_report("Using more than 256 vcpus requires a host kernel "
+                     "with KVM_CAP_ARM_IRQ_LINE_LAYOUT_2");
+        ret = -EINVAL;
+    }
+
+    return ret;
 }
 
 unsigned long kvm_arch_vcpu_id(CPUState *cpu)