--- a/sys/platform/pc64/x86_64/mptable.c	2026-10-03 04:37:03.595609252 +0000
+++ b/sys/platform/pc64/x86_64/mptable.c	2026-10-03 04:37:03.627608844 +0000
@@ -680,6 +680,13 @@
 		return 0;
 	ent = pos;
 
+	/*
+	 * Match probe semantics (mptable_lapic_probe_callback):
+	 * disabled entries carry no BSP information.
+	 */
+	if ((ent->cpu_flags & PROCENTRY_FLAG_EN) == 0)
+		return 0;
+
 	if (ent->cpu_flags & PROCENTRY_FLAG_BP) {
 		KKASSERT(!arg->found_bsp);
 		arg->found_bsp = 1;