diff --git a/[refs] b/[refs]
index ee13118e0808..102a61be2572 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 6206ab9bab620fc0fbbed30ce20d145b0b3d1840
+refs/heads/master: 4627e240dfee4a0a46a58010b1b721b4ded1918f
diff --git a/trunk/kernel/rcutree.c b/trunk/kernel/rcutree.c
index ebd18e56947b..a07bf553e02a 100644
--- a/trunk/kernel/rcutree.c
+++ b/trunk/kernel/rcutree.c
@@ -583,7 +583,8 @@ static void print_other_cpu_stall(struct rcu_state *rsp)
 	}
 	printk("} (detected by %d, t=%ld jiffies)\n",
 	       smp_processor_id(), (long)(jiffies - rsp->gp_start));
-	trigger_all_cpu_backtrace();
+	if (!trigger_all_cpu_backtrace())
+		dump_stack();
 
 	/* If so configured, complain about tasks blocking the grace period. */
 
@@ -604,7 +605,8 @@ static void print_cpu_stall(struct rcu_state *rsp)
 	 */
 	printk(KERN_ERR "INFO: %s detected stall on CPU %d (t=%lu jiffies)\n",
 	       rsp->name, smp_processor_id(), jiffies - rsp->gp_start);
-	trigger_all_cpu_backtrace();
+	if (!trigger_all_cpu_backtrace())
+		dump_stack();
 
 	raw_spin_lock_irqsave(&rnp->lock, flags);
 	if (ULONG_CMP_GE(jiffies, rsp->jiffies_stall))