Index: sys/kern/kern_malloc.c
===================================================================
--- sys/kern/kern_malloc.c
+++ sys/kern/kern_malloc.c
@@ -472,9 +472,12 @@
 		}
 	}
 #endif
-	if (flags & M_WAITOK)
+	if (flags & M_WAITOK) {
 		KASSERT(curthread->td_intr_nesting_level == 0,
 		   ("malloc(M_WAITOK) in interrupt context"));
+		KASSERT_WARN(THREAD_CAN_SLEEP(),
+		    ("malloc(M_WAITOK) in no_sleeping context"));
+	}
 
 #ifdef DEBUG_MEMGUARD
 	if (memguard_cmp_mtp(mtp, size)) {
Index: sys/vm/uma_core.c
===================================================================
--- sys/vm/uma_core.c
+++ sys/vm/uma_core.c
@@ -2109,6 +2109,10 @@
 	if (flags & M_WAITOK) {
 		WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
 		    "uma_zalloc_arg: zone \"%s\"", zone->uz_name);
+		KASSERT_WARN(curthread->td_intr_nesting_level == 0,
+		   ("uma_zalloc_arg(M_WAITOK) in interrupt context"));
+		KASSERT_WARN(THREAD_CAN_SLEEP(),
+		    ("uma_zalloc_arg(M_WAITOK) in no_sleeping context"));
 	}
 #ifdef DEBUG_MEMGUARD
 	if (memguard_cmp_zone(zone)) {