[SPARC]: Fix do_gettimeofday() as per cset 1.1347.1.17

arch/sparc/kernel/pcic.c

@@ -785,6 +785,15 @@ static void pci_do_gettimeofday(struct timeval *tv)
 			if (lost)
 				usec += lost * (1000000 / HZ);
 		}
+
+		/*
+		 * If time_adjust is negative then NTP is slowing the clock
+		 * so make sure not to go into next possible interval.
+		 * Better to lose some accuracy than have time go backwards..
+		 */
+		if (unlikely(time_adjust < 0) && usec > tickadj)
+			usec = tickadj;
+
 		sec = xtime.tv_sec;
 		usec += (xtime.tv_nsec / 1000);
 	} while (read_seqretry_irqrestore(&xtime_lock, seq, flags));

arch/sparc/kernel/time.c

@@ -490,6 +490,15 @@ void do_gettimeofday(struct timeval *tv)
 			if (lost)
 				usec += lost * (1000000 / HZ);
 		}
+
+		/*
+		 * If time_adjust is negative then NTP is slowing the clock
+		 * so make sure not to go into next possible interval.
+		 * Better to lose some accuracy than have time go backwards..
+		 */
+		if (unlikely(time_adjust < 0) && usec > tickadj)
+			usec = tickadj;
+
 		sec = xtime.tv_sec;
 		usec += (xtime.tv_nsec / 1000);
 	} while (read_seqretry_irqrestore(&xtime_lock, seq, flags));

arch/sparc64/kernel/time.c

@@ -1149,6 +1149,15 @@ void do_gettimeofday(struct timeval *tv)
 			if (lost)
 				usec += lost * (1000000 / HZ);
 		}
+
+		/*
+		 * If time_adjust is negative then NTP is slowing the clock
+		 * so make sure not to go into next possible interval.
+		 * Better to lose some accuracy than have time go backwards..
+		 */
+		if (unlikely(time_adjust < 0) && usec > tickadj)
+			usec = tickadj;
+
 		sec = xtime.tv_sec;
 		usec += (xtime.tv_nsec / 1000);
 	} while (read_seqretry_irqrestore(&xtime_lock, seq, flags));