diff --git a/sys/kern/kern_ktr.c b/sys/kern/kern_ktr.c
index 3202b9b..2c9c53f 100644
--- a/sys/kern/kern_ktr.c
+++ b/sys/kern/kern_ktr.c
@@ -98,6 +98,7 @@ static MALLOC_DEFINE(M_KTR, "KTR", "KTR");
 FEATURE(ktr, "Kernel support for KTR kernel tracing facility");
 
 volatile int	ktr_idx = 0;
+volatile int	ktr_overflow = 0;	/* Overflow detection during boot */
 int	ktr_mask = KTR_MASK;
 int	ktr_compile = KTR_COMPILE;
 int	ktr_entries = KTR_BOOT_ENTRIES;
@@ -213,13 +214,19 @@ ktr_entries_initializer(void *dummy __unused)
 	ktr_mask = 0;
 	ktr_buf = malloc(sizeof(*ktr_buf) * KTR_ENTRIES, M_KTR,
 	    M_WAITOK | M_ZERO);
-	memcpy(ktr_buf, ktr_buf_init + ktr_idx,
-	    (KTR_BOOT_ENTRIES - ktr_idx) * sizeof(*ktr_buf));
-	if (ktr_idx != 0)
-		memcpy(ktr_buf + KTR_BOOT_ENTRIES - ktr_idx, ktr_buf_init,
-		    ktr_idx * sizeof(*ktr_buf));
+	if (ktr_overflow >= KTR_BOOT_ENTRIES) {
+		memcpy(ktr_buf, ktr_buf_init + ktr_idx,
+	    		(KTR_BOOT_ENTRIES - ktr_idx) * sizeof(*ktr_buf));
+		if (ktr_idx != 0)
+			memcpy(ktr_buf + KTR_BOOT_ENTRIES - ktr_idx,
+		    ktr_buf_init, ktr_idx * sizeof(*ktr_buf));
+	}
+	else
+		memcpy(ktr_buf, ktr_buf_init, ktr_idx * sizeof(*ktr_buf));
 	ktr_entries = KTR_ENTRIES;
 	ktr_mask = mask;
+	free(ktr_buf_init, M_KTR);
+	ktr_buf_init = NULL;
 }
 SYSINIT(ktr_entries_initializer, SI_SUB_KMEM, SI_ORDER_ANY,
     ktr_entries_initializer, NULL);
@@ -380,6 +387,9 @@ ktr_tracepoint(u_int mask, const char *file, int line, const char *format,
 			saveindex = ktr_idx;
 			newindex = (saveindex + 1) % ktr_entries;
 		} while (atomic_cmpset_rel_int(&ktr_idx, saveindex, newindex) == 0);
+		/* This happens only in early boot */
+		if (ktr_buf_init != NULL)
+			ktr_overflow++;
 		entry = &ktr_buf[saveindex];
 	}
 	entry->ktr_timestamp = KTR_TIME;