diff -urN oldtree/include/linux/rcuclassic.h newtree/include/linux/rcuclassic.h
--- oldtree/include/linux/rcuclassic.h	2006-09-26 19:08:59.000000000 -0400
+++ newtree/include/linux/rcuclassic.h	2006-09-26 19:09:46.000000000 -0400
@@ -115,25 +115,37 @@
 extern int rcu_pending(int cpu);
 extern int rcu_needs_cpu(int cpu);
 
+#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
+extern void rcu_add_read_count(void);
+extern void rcu_sub_read_count(void);
+#else
+static inline void rcu_add_read_count(void) {}
+static inline void rcu_sub_read_count(void) {}
+#endif
+
 #define __rcu_read_lock() \
 	do { \
 		preempt_disable(); \
+		rcu_add_read_count(); \
 		__acquire(RCU); \
 	} while(0)
 #define __rcu_read_unlock() \
 	do { \
 		__release(RCU); \
+		rcu_sub_read_count(); \
 		preempt_enable(); \
 	} while(0)
 
 #define __rcu_read_lock_bh() \
 	do { \
 		local_bh_disable(); \
+		rcu_add_read_count(); \
 		__acquire(RCU_BH); \
 	} while(0)
 #define __rcu_read_unlock_bh() \
 	do { \
 		__release(RCU_BH); \
+		rcu_sub_read_count(); \
 		local_bh_enable(); \
 	} while(0)
 
diff -urN oldtree/include/linux/rcupdate.h newtree/include/linux/rcupdate.h
--- oldtree/include/linux/rcupdate.h	2006-09-26 19:08:59.000000000 -0400
+++ newtree/include/linux/rcupdate.h	2006-09-26 19:09:46.000000000 -0400
@@ -64,6 +64,12 @@
        (ptr)->next = NULL; (ptr)->func = NULL; \
 } while (0)
 
+#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
+extern int rcu_read_in_atomic(void);
+#else
+static inline int rcu_read_in_atomic(void) { return 0;}
+#endif
+
 /**
  * rcu_read_lock - mark the beginning of an RCU read-side critical section.
  *
diff -urN oldtree/kernel/rcuclassic.c newtree/kernel/rcuclassic.c
--- oldtree/kernel/rcuclassic.c	2006-09-26 19:08:21.000000000 -0400
+++ newtree/kernel/rcuclassic.c	2006-09-26 19:09:46.000000000 -0400
@@ -545,6 +545,39 @@
 	register_cpu_notifier(&rcu_nb);
 }
 
+#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
+static DEFINE_PER_CPU(int, rcu_read_count);
+int rcu_read_in_atomic(void)
+{
+	int val;
+	int cpu = get_cpu();
+	val = per_cpu(rcu_read_count, cpu);
+	put_cpu();
+	return val;
+}
+
+void rcu_add_read_count(void)
+{
+	int cpu, flags;
+	local_irq_save(flags);
+	cpu = smp_processor_id();
+	per_cpu(rcu_read_count, cpu)++;
+	local_irq_restore(flags);
+}
+
+void rcu_sub_read_count(void)
+{
+	int cpu, flags;
+	local_irq_save(flags);
+	cpu = smp_processor_id();
+	per_cpu(rcu_read_count, cpu)--;
+	local_irq_restore(flags);
+}
+EXPORT_SYMBOL_GPL(rcu_read_in_atomic);
+EXPORT_SYMBOL_GPL(rcu_add_read_count);
+EXPORT_SYMBOL_GPL(rcu_sub_read_count);
+#endif
+
 module_param(blimit, int, 0);
 module_param(qhimark, int, 0);
 module_param(qlowmark, int, 0);
diff -urN oldtree/kernel/rcupreempt.c newtree/kernel/rcupreempt.c
--- oldtree/kernel/rcupreempt.c	2006-09-26 19:09:35.000000000 -0400
+++ newtree/kernel/rcupreempt.c	2006-09-26 19:09:46.000000000 -0400
@@ -424,6 +424,13 @@
 
 #endif /* #ifdef CONFIG_RCU_TRACE */
 
+#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
+int rcu_read_in_atomic(void)
+{
+	return current->rcu_read_lock_nesting;
+}
+#endif
+
 EXPORT_SYMBOL_GPL(call_rcu);
 EXPORT_SYMBOL_GPL(rcu_batches_completed);
 EXPORT_SYMBOL_GPL(rcu_batches_completed_bh);
diff -urN oldtree/kernel/sched_ingosched.c newtree/kernel/sched_ingosched.c
--- oldtree/kernel/sched_ingosched.c	2006-09-26 14:34:25.000000000 -0400
+++ newtree/kernel/sched_ingosched.c	2006-09-26 19:10:17.000000000 -0400
@@ -6968,7 +6968,7 @@
 #ifdef in_atomic
 	static unsigned long prev_jiffy;	/* ratelimiting */
 
-	if ((in_atomic() || irqs_disabled()) &&
+        if ((in_atomic() || irqs_disabled() || rcu_read_in_atomic()) &&
 	    system_state == SYSTEM_RUNNING && !oops_in_progress) {
 		if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy)
 			return;
diff -urN oldtree/kernel/sched_staircase.c newtree/kernel/sched_staircase.c
--- oldtree/kernel/sched_staircase.c	2006-09-26 16:09:47.000000000 -0400
+++ newtree/kernel/sched_staircase.c	2006-09-26 19:10:29.000000000 -0400
@@ -6891,7 +6891,7 @@
 #ifdef in_atomic
 	static unsigned long prev_jiffy;	/* ratelimiting */
 
-	if ((in_atomic() || irqs_disabled()) &&
+        if ((in_atomic() || irqs_disabled() || rcu_read_in_atomic()) &&
 	    system_state == SYSTEM_RUNNING && !oops_in_progress) {
 		if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy)
 			return;