diff --git a/debian/changelog b/debian/changelog
index b9edbf17b..b9dc99e2d 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,6 +1,7 @@
 linux (4.4~rc6-1~exp2) UNRELEASED; urgency=medium
 
   * [rt] Update to 4.4-rc6-rt1 and re-enable
+  * [rt] Fix build error in kernel/time/hrtimer.c
 
  -- Ben Hutchings <ben@decadent.org.uk>  Thu, 24 Dec 2015 21:28:51 +0000
 
diff --git a/debian/patches/features/all/rt/hrtimer-fixup-hrtimer-callback-changes-for-preempt-r.patch b/debian/patches/features/all/rt/hrtimer-fixup-hrtimer-callback-changes-for-preempt-r.patch
index b7b3e31e1..1e653d94d 100644
--- a/debian/patches/features/all/rt/hrtimer-fixup-hrtimer-callback-changes-for-preempt-r.patch
+++ b/debian/patches/features/all/rt/hrtimer-fixup-hrtimer-callback-changes-for-preempt-r.patch
@@ -11,7 +11,7 @@ delivery problem for real.
 
 Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
 Signed-off-by: Ingo Molnar <mingo@elte.hu>
-
+[bwh: Adjust context to apply after fixed latency-hist.patch]
 ---
  include/linux/hrtimer.h  |    4 +
  kernel/sched/core.c      |    1 
@@ -121,7 +121,7 @@ Signed-off-by: Ingo Molnar <mingo@elte.hu>
  		    cpu_base->running == timer)
  			return true;
  
-@@ -1292,10 +1296,111 @@ static void __run_hrtimer(struct hrtimer
+@@ -1292,12 +1296,113 @@ static void __run_hrtimer(struct hrtimer
  	cpu_base->running = NULL;
  }
  
@@ -225,6 +225,8 @@ Signed-off-by: Ingo Molnar <mingo@elte.hu>
 +#endif
 +
 +
+ static enum hrtimer_restart hrtimer_wakeup(struct hrtimer *timer);
+ 
  static void __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t now)
  {
  	struct hrtimer_clock_base *base = cpu_base->clock_base;
@@ -233,7 +235,7 @@ Signed-off-by: Ingo Molnar <mingo@elte.hu>
  
  	for (; active; base++, active >>= 1) {
  		struct timerqueue_node *node;
-@@ -1335,15 +1440,20 @@ static void __hrtimer_run_queues(struct
+@@ -1337,9 +1442,14 @@ static void __hrtimer_run_queues(struct
  			if (basenow.tv64 < hrtimer_get_softexpires_tv64(timer))
  				break;
  
@@ -248,15 +250,7 @@ Signed-off-by: Ingo Molnar <mingo@elte.hu>
 +		raise_softirq_irqoff(HRTIMER_SOFTIRQ);
  }
  
--#ifdef CONFIG_HIGH_RES_TIMERS
--
- static enum hrtimer_restart hrtimer_wakeup(struct hrtimer *timer);
- 
-+#ifdef CONFIG_HIGH_RES_TIMERS
-+
- /*
-  * High resolution timer interrupt
-  * Called with interrupts disabled
+ #ifdef CONFIG_HIGH_RES_TIMERS
 @@ -1481,8 +1591,6 @@ void hrtimer_run_queues(void)
  	now = hrtimer_update_base(cpu_base);
  	__hrtimer_run_queues(cpu_base, now);
diff --git a/debian/patches/features/all/rt/latency-hist.patch b/debian/patches/features/all/rt/latency-hist.patch
index 39f454ba5..88a5464c2 100644
--- a/debian/patches/features/all/rt/latency-hist.patch
+++ b/debian/patches/features/all/rt/latency-hist.patch
@@ -12,7 +12,7 @@ filesystem. For details please consult Documentation/trace/histograms.txt.
 
 Signed-off-by: Carsten Emde <C.Emde@osadl.org>
 Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
-
+[bwh: Move up prototype of hrtimer_wakeup() so this actually compiles]
 ---
  Documentation/trace/histograms.txt  |  186 +++++
  include/linux/hrtimer.h             |    3 
@@ -376,7 +376,16 @@ Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  	leftmost = enqueue_hrtimer(timer, new_base);
  	if (!leftmost)
  		goto unlock;
-@@ -1275,6 +1285,15 @@ static void __hrtimer_run_queues(struct
+@@ -1256,6 +1266,8 @@ static void __run_hrtimer(struct hrtimer
+ 	cpu_base->running = NULL;
+ }
+ 
++static enum hrtimer_restart hrtimer_wakeup(struct hrtimer *timer);
++
+ static void __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t now)
+ {
+ 	struct hrtimer_clock_base *base = cpu_base->clock_base;
+@@ -1275,6 +1287,15 @@ static void __hrtimer_run_queues(struct
  
  			timer = container_of(node, struct hrtimer, node);
  
@@ -392,15 +401,6 @@ Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  			/*
  			 * The immediate goal for using the softexpires is
  			 * minimizing wakeups, not running timers at the
-@@ -1297,6 +1316,8 @@ static void __hrtimer_run_queues(struct
- 
- #ifdef CONFIG_HIGH_RES_TIMERS
- 
-+static enum hrtimer_restart hrtimer_wakeup(struct hrtimer *timer);
-+
- /*
-  * High resolution timer interrupt
-  * Called with interrupts disabled
 --- a/kernel/trace/Kconfig
 +++ b/kernel/trace/Kconfig
 @@ -187,6 +187,24 @@ config IRQSOFF_TRACER
@@ -1784,7 +1784,7 @@ Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  	if (!preempt_trace() && irq_trace())
  		stop_critical_timing(CALLER_ADDR0, caller_addr);
  }
-@@ -490,6 +498,7 @@ EXPORT_SYMBOL(trace_hardirqs_on_caller);
+@@ -490,6 +498,7 @@ __visible void trace_hardirqs_off_caller
  {
  	if (!preempt_trace() && irq_trace())
  		start_critical_timing(CALLER_ADDR0, caller_addr);