diff --git a/fs/proc/base.c b/fs/proc/base.c
index 92e37e224cd2..0d163a84082d 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -434,7 +434,7 @@ static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns,
 			&& !lookup_symbol_name(wchan, symname))
 		seq_printf(m, "%s", symname);
 	else
-		seq_puts(m, "0\n");
+		seq_putc(m, '0');
 
 	return 0;
 }
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index e72efb109fde..fe47fbba995a 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -1735,10 +1735,13 @@ static struct page *isolate_source_page(struct size_class *class)
 static unsigned long zs_can_compact(struct size_class *class)
 {
 	unsigned long obj_wasted;
+	unsigned long obj_allocated = zs_stat_get(class, OBJ_ALLOCATED);
+	unsigned long obj_used = zs_stat_get(class, OBJ_USED);
 
-	obj_wasted = zs_stat_get(class, OBJ_ALLOCATED) -
-		zs_stat_get(class, OBJ_USED);
+	if (obj_allocated <= obj_used)
+		return 0;
 
+	obj_wasted = obj_allocated - obj_used;
 	obj_wasted /= get_maxobj_per_zspage(class->size,
 			class->pages_per_zspage);