3 files changed, 20 insertions, 1 deletions

diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 5d910beefff2..5aab7dabd0d5 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -144,7 +144,7 @@ module_param(qhimark, int, 0);
 module_param(qlowmark, int, 0);
 
 #ifdef CONFIG_RCU_CPU_STALL_DETECTOR
-int rcu_cpu_stall_suppress __read_mostly;
+int rcu_cpu_stall_suppress __read_mostly = RCU_CPU_STALL_SUPPRESS_INIT;
 module_param(rcu_cpu_stall_suppress, int, 0644);
 #endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
 
diff --git a/kernel/rcutree.h b/kernel/rcutree.h
index 183ebf405315..bb4d08695c45 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@ -264,6 +264,12 @@ struct rcu_data {
                                                 /*  scheduling clock irq */
                                                 /*  before ratting on them. */
 
+#ifdef CONFIG_RCU_CPU_STALL_DETECTOR_RUNNABLE
+#define RCU_CPU_STALL_SUPPRESS_INIT 0
+#else
+#define RCU_CPU_STALL_SUPPRESS_INIT 1
+#endif
+
 #endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
 
 #define ULONG_CMP_GE(a, b)      (ULONG_MAX / 2 >= (a) - (b))
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index b5005b762103..52c2172dff16 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -856,6 +856,19 @@ config RCU_CPU_STALL_TIMEOUT
           RCU grace period persists, additional CPU stall warnings are
           printed at more widely spaced intervals.
 
+config RCU_CPU_STALL_DETECTOR_RUNNABLE
+        bool "RCU CPU stall checking starts automatically at boot"
+        depends on RCU_CPU_STALL_DETECTOR
+        default y
+        help
+          If set, start checking for RCU CPU stalls immediately on
+          boot.  Otherwise, RCU CPU stall checking must be manually
+          enabled.
+
+          Say Y if you are unsure.
+
+          Say N if you wish to suppress RCU CPU stall checking during boot.
+
 config RCU_CPU_STALL_VERBOSE
         bool "Print additional per-task information for RCU_CPU_STALL_DETECTOR"
         depends on RCU_CPU_STALL_DETECTOR && TREE_PREEMPT_RCU