Index: sys/vm/vm_page.c
===================================================================
--- sys/vm/vm_page.c
+++ sys/vm/vm_page.c
@@ -900,9 +900,11 @@
 		    (allocflags & VM_ALLOC_SBUSY) != 0, locked);
 		if (locked)
 			VM_OBJECT_WLOCK(obj);
-		MPASS(m->object == obj || m->object == NULL);
 		if ((allocflags & VM_ALLOC_WAITFAIL) != 0)
 			return (FALSE);
+		KASSERT(m->object == obj || m->object == NULL,
+		    ("vm_page_busy_acquire: page %p does not belong to %p",
+		    m, obj));
 	}
 }
 
Index: sys/vm/vnode_pager.c
===================================================================
--- sys/vm/vnode_pager.c
+++ sys/vm/vnode_pager.c
@@ -1149,6 +1149,8 @@
 
 		nextoff = tfoff + PAGE_SIZE;
 		mt = bp->b_pages[i];
+		if (mt == bogus_page)
+			continue;
 
 		if (nextoff <= object->un_pager.vnp.vnp_size) {
 			/*