diff --git a/Documentation/RCU/stallwarn.txt b/Documentation/RCU/stallwarn.txt
index 5abea29b41a0..50833568cb10 100644
--- a/Documentation/RCU/stallwarn.txt
+++ b/Documentation/RCU/stallwarn.txt
@@ -139,6 +139,15 @@ no non-lazy callbacks ("." is printed otherwise, as shown above) and
 "D" indicates that dyntick-idle processing is enabled ("." is printed
 otherwise, for example, if disabled via the "nohz=" kernel boot parameter).
 
+If the relevant grace-period kthread has been unable to run prior to
+the stall warning, the following additional line is printed:
+
+	rcu_preempt kthread starved for 2023 jiffies!
+
+Starving the grace-period kthreads of CPU time can of course result in
+RCU CPU stall warnings even when all CPUs and tasks have passed through
+the required quiescent states.
+
 
 Multiple Warnings From One Stall
 
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 68a28c78189c..fc3abf16cc22 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -826,6 +826,21 @@ static void record_gp_stall_check_time(struct rcu_state *rsp)
 	rsp->n_force_qs_gpstart = ACCESS_ONCE(rsp->n_force_qs);
 }
 
+/*
+ * Complain about starvation of grace-period kthread.
+ */
+static void rcu_check_gp_kthread_starvation(struct rcu_state *rsp)
+{
+	unsigned long gpa;
+	unsigned long j;
+
+	j = jiffies;
+	gpa = ACCESS_ONCE(rsp->gp_activity);
+	if (j - gpa > 2 * HZ)
+		pr_err("%s kthread starved for %ld jiffies!\n",
+		       rsp->name, j - gpa);
+}
+
 /*
  * Dump stacks of all tasks running on stalled CPUs.  This is a fallback
  * for architectures that do not implement trigger_all_cpu_backtrace().
@@ -926,9 +941,10 @@ static void print_other_cpu_stall(struct rcu_state *rsp, unsigned long gpnum)
 	}
 
 	/* Complain about tasks blocking the grace period. */
-
 	rcu_print_detail_task_stall(rsp);
 
+	rcu_check_gp_kthread_starvation(rsp);
+
 	force_quiescent_state(rsp);  /* Kick them all. */
 }
 
@@ -952,6 +968,9 @@ static void print_cpu_stall(struct rcu_state *rsp)
 		totqlen += per_cpu_ptr(rsp->rda, cpu)->qlen;
 	pr_cont(" (t=%lu jiffies g=%lu c=%lu q=%lu)\n",
 		jiffies - rsp->gp_start, rsp->gpnum, rsp->completed, totqlen);
+
+	rcu_check_gp_kthread_starvation(rsp);
+
 	if (!trigger_all_cpu_backtrace())
 		dump_stack();