percpu: resolve err may not be initialized in pcpu_alloc

From 4a42ecc735cff0015cc73c3d87edede631f4b885 Mon Sep 17 00:00:00 2001
From: Dennis Zhou <dennisz@fb.com>
Date: Wed, 21 Jun 2017 08:07:15 -0700

Add error message to out of space failure for atomic allocations in
percpu allocation path to fix -Wmaybe-uninitialized.

Signed-off-by: Dennis Zhou <dennisz@fb.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/mm/percpu.c b/mm/percpu.c
index a5bc3634d2a9..bd4130a69bbc 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -956,8 +956,10 @@ restart:
          * tasks to create chunks simultaneously.  Serialize and create iff
          * there's still no empty chunk after grabbing the mutex.
          */
-        if (is_atomic)
+        if (is_atomic) {
+                err = "atomic alloc failed, no space left";
                 goto fail;
+        }
 
         if (list_empty(&pcpu_slot[pcpu_nr_slots - 1])) {
                 chunk = pcpu_create_chunk();