diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index 600fc3bcf63e..1ad56a7b2f74 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -316,7 +316,7 @@ static inline u64 hrtimer_forward_now(struct hrtimer *timer,
 
 /* Precise sleep: */
 extern long hrtimer_nanosleep(struct timespec *rqtp,
-			      struct timespec *rmtp,
+			      struct timespec __user *rmtp,
 			      const enum hrtimer_mode mode,
 			      const clockid_t clockid);
 extern long hrtimer_nanosleep_restart(struct restart_block *restart_block);
diff --git a/include/linux/timex.h b/include/linux/timex.h
index 8ea3e71ba7fa..c3f374786a43 100644
--- a/include/linux/timex.h
+++ b/include/linux/timex.h
@@ -232,7 +232,14 @@ static inline int ntp_synced(void)
 #else
 #define NTP_INTERVAL_FREQ  (HZ)
 #endif
-#define NTP_INTERVAL_LENGTH (NSEC_PER_SEC/NTP_INTERVAL_FREQ)
+
+#define CLOCK_TICK_OVERFLOW	(LATCH * HZ - CLOCK_TICK_RATE)
+#define CLOCK_TICK_ADJUST	(((s64)CLOCK_TICK_OVERFLOW * NSEC_PER_SEC) / \
+					(s64)CLOCK_TICK_RATE)
+
+/* Because using NSEC_PER_SEC would be too easy */
+#define NTP_INTERVAL_LENGTH ((((s64)TICK_USEC * NSEC_PER_USEC * USER_HZ) + \
+			      CLOCK_TICK_ADJUST) / NTP_INTERVAL_FREQ)
 
 /* Returns how long ticks are at present, in ns / 2^(SHIFT_SCALE-10). */
 extern u64 current_tick_length(void);
diff --git a/kernel/compat.c b/kernel/compat.c
index 42a1ed4b61b1..5f0e201bcfd3 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -40,10 +40,35 @@ int put_compat_timespec(const struct timespec *ts, struct compat_timespec __user
 			__put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
 }
 
+static long compat_nanosleep_restart(struct restart_block *restart)
+{
+	struct compat_timespec __user *rmtp;
+	struct timespec rmt;
+	mm_segment_t oldfs;
+	long ret;
+
+	rmtp = (struct compat_timespec __user *)(restart->arg1);
+	restart->arg1 = (unsigned long)&rmt;
+	oldfs = get_fs();
+	set_fs(KERNEL_DS);
+	ret = hrtimer_nanosleep_restart(restart);
+	set_fs(oldfs);
+
+	if (ret) {
+		restart->arg1 = (unsigned long)rmtp;
+
+		if (rmtp && put_compat_timespec(&rmt, rmtp))
+			return -EFAULT;
+	}
+
+	return ret;
+}
+
 asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp,
 				     struct compat_timespec __user *rmtp)
 {
 	struct timespec tu, rmt;
+	mm_segment_t oldfs;
 	long ret;
 
 	if (get_compat_timespec(&tu, rqtp))
@@ -52,11 +77,21 @@ asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp,
 	if (!timespec_valid(&tu))
 		return -EINVAL;
 
-	ret = hrtimer_nanosleep(&tu, rmtp ? &rmt : NULL, HRTIMER_MODE_REL,
-				CLOCK_MONOTONIC);
+	oldfs = get_fs();
+	set_fs(KERNEL_DS);
+	ret = hrtimer_nanosleep(&tu,
+				rmtp ? (struct timespec __user *)&rmt : NULL,
+				HRTIMER_MODE_REL, CLOCK_MONOTONIC);
+	set_fs(oldfs);
 
-	if (ret && rmtp) {
-		if (put_compat_timespec(&rmt, rmtp))
+	if (ret) {
+		struct restart_block *restart
+			= &current_thread_info()->restart_block;
+
+		restart->fn = compat_nanosleep_restart;
+		restart->arg1 = (unsigned long)rmtp;
+
+		if (rmtp && put_compat_timespec(&rmt, rmtp))
 			return -EFAULT;
 	}
 
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 668f3967eb39..3f4a57c7895d 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -1319,13 +1319,26 @@ static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mod
 	return t->task == NULL;
 }
 
+static int update_rmtp(struct hrtimer *timer, struct timespec __user *rmtp)
+{
+	struct timespec rmt;
+	ktime_t rem;
+
+	rem = ktime_sub(timer->expires, timer->base->get_time());
+	if (rem.tv64 <= 0)
+		return 0;
+	rmt = ktime_to_timespec(rem);
+
+	if (copy_to_user(rmtp, &rmt, sizeof(*rmtp)))
+		return -EFAULT;
+
+	return 1;
+}
+
 long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
 {
 	struct hrtimer_sleeper t;
-	struct timespec *rmtp;
-	ktime_t time;
-
-	restart->fn = do_no_restart_syscall;
+	struct timespec __user  *rmtp;
 
 	hrtimer_init(&t.timer, restart->arg0, HRTIMER_MODE_ABS);
 	t.timer.expires.tv64 = ((u64)restart->arg3 << 32) | (u64) restart->arg2;
@@ -1333,26 +1346,22 @@ long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
 	if (do_nanosleep(&t, HRTIMER_MODE_ABS))
 		return 0;
 
-	rmtp = (struct timespec *)restart->arg1;
+	rmtp = (struct timespec __user *)restart->arg1;
 	if (rmtp) {
-		time = ktime_sub(t.timer.expires, t.timer.base->get_time());
-		if (time.tv64 <= 0)
-			return 0;
-		*rmtp = ktime_to_timespec(time);
+		int ret = update_rmtp(&t.timer, rmtp);
+		if (ret <= 0)
+			return ret;
 	}
 
-	restart->fn = hrtimer_nanosleep_restart;
-
 	/* The other values in restart are already filled in */
 	return -ERESTART_RESTARTBLOCK;
 }
 
-long hrtimer_nanosleep(struct timespec *rqtp, struct timespec *rmtp,
+long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
 		       const enum hrtimer_mode mode, const clockid_t clockid)
 {
 	struct restart_block *restart;
 	struct hrtimer_sleeper t;
-	ktime_t rem;
 
 	hrtimer_init(&t.timer, clockid, mode);
 	t.timer.expires = timespec_to_ktime(*rqtp);
@@ -1364,10 +1373,9 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec *rmtp,
 		return -ERESTARTNOHAND;
 
 	if (rmtp) {
-		rem = ktime_sub(t.timer.expires, t.timer.base->get_time());
-		if (rem.tv64 <= 0)
-			return 0;
-		*rmtp = ktime_to_timespec(rem);
+		int ret = update_rmtp(&t.timer, rmtp);
+		if (ret <= 0)
+			return ret;
 	}
 
 	restart = &current_thread_info()->restart_block;
@@ -1383,8 +1391,7 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec *rmtp,
 asmlinkage long
 sys_nanosleep(struct timespec __user *rqtp, struct timespec __user *rmtp)
 {
-	struct timespec tu, rmt;
-	int ret;
+	struct timespec tu;
 
 	if (copy_from_user(&tu, rqtp, sizeof(tu)))
 		return -EFAULT;
@@ -1392,15 +1399,7 @@ sys_nanosleep(struct timespec __user *rqtp, struct timespec __user *rmtp)
 	if (!timespec_valid(&tu))
 		return -EINVAL;
 
-	ret = hrtimer_nanosleep(&tu, rmtp ? &rmt : NULL, HRTIMER_MODE_REL,
-				CLOCK_MONOTONIC);
-
-	if (ret && rmtp) {
-		if (copy_to_user(rmtp, &rmt, sizeof(*rmtp)))
-			return -EFAULT;
-	}
-
-	return ret;
+	return hrtimer_nanosleep(&tu, rmtp, HRTIMER_MODE_REL, CLOCK_MONOTONIC);
 }
 
 /*
diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index ce268966007d..022c9c3cee6f 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -982,20 +982,9 @@ sys_clock_getres(const clockid_t which_clock, struct timespec __user *tp)
 static int common_nsleep(const clockid_t which_clock, int flags,
 			 struct timespec *tsave, struct timespec __user *rmtp)
 {
-	struct timespec rmt;
-	int ret;
-
-	ret = hrtimer_nanosleep(tsave, rmtp ? &rmt : NULL,
-				flags & TIMER_ABSTIME ?
-				HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
-				which_clock);
-
-	if (ret && rmtp) {
-		if (copy_to_user(rmtp, &rmt, sizeof(*rmtp)))
-			return -EFAULT;
-	}
-
-	return ret;
+	return hrtimer_nanosleep(tsave, rmtp, flags & TIMER_ABSTIME ?
+				 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
+				 which_clock);
 }
 
 asmlinkage long
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index e64efaf957e8..c88b5910e7ab 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -43,10 +43,6 @@ long time_freq;				/* frequency offset (scaled ppm)*/
 static long time_reftime;		/* time at last adjustment (s)	*/
 long time_adjust;
 
-#define CLOCK_TICK_OVERFLOW	(LATCH * HZ - CLOCK_TICK_RATE)
-#define CLOCK_TICK_ADJUST	(((s64)CLOCK_TICK_OVERFLOW * NSEC_PER_SEC) / \
-					(s64)CLOCK_TICK_RATE)
-
 static void ntp_update_frequency(void)
 {
 	u64 second_length = (u64)(tick_usec * NSEC_PER_USEC * USER_HZ)