diff --git a/sys/x86/x86/mp_x86.c b/sys/x86/x86/mp_x86.c
index b4c66a58faa5..c23108cc7ad6 100644
--- a/sys/x86/x86/mp_x86.c
+++ b/sys/x86/x86/mp_x86.c
@@ -602,7 +602,7 @@ init_secondary_tail(void)
 	mtx_unlock_spin(&ap_boot_mtx);
 
 	/* Wait until all the AP's are up. */
-	while (smp_started == 0)
+	while (atomic_load_acq_int(&smp_started) == 0)
 		ia32_pause();
 
 	/* Start per-CPU event timers. */