diff --git a/sys/x86/x86/local_apic.c b/sys/x86/x86/local_apic.c
--- a/sys/x86/x86/local_apic.c
+++ b/sys/x86/x86/local_apic.c
@@ -2127,6 +2127,10 @@
 
 #endif /* SMP */
 
+#ifdef __i386__
+extern uintptr_t setidt_disp;
+#endif
+
 /*
  * Since the IDT is shared by all CPUs the IPI slot update needs to be globally
  * visible.
@@ -2155,6 +2159,9 @@
 	for (idx = IPI_DYN_FIRST; idx <= IPI_DYN_LAST; idx++) {
 		ip = &idt[idx];
 		func = (ip->gd_hioffset << 16) | ip->gd_looffset;
+#ifdef __i386__
+		func -= setidt_disp;
+#endif
 		if ((!pti && func == (uintptr_t)&IDTVEC(rsvd)) ||
 		    (pti && func == (uintptr_t)&IDTVEC(rsvd_pti))) {
 			vector = idx;
@@ -2178,6 +2185,9 @@
 	mtx_lock_spin(&icu_lock);
 	ip = &idt[vector];
 	func = (ip->gd_hioffset << 16) | ip->gd_looffset;
+#ifdef __i386__
+	func -= setidt_disp;
+#endif
 	KASSERT(func != (uintptr_t)&IDTVEC(rsvd) &&
 	    func != (uintptr_t)&IDTVEC(rsvd_pti),
 	    ("invalid idtfunc %#lx", func));