Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing: Fix null pointer deref with SEND_SIG_FORCED
  perf: Fix signed comparison in perf_adjust_period()
  powerpc/oprofile: fix potential buffer overrun in op_model_cell.c
  perf symbols: Set the DSO long name when using symbol_conf.vmlinux_name

1 files changed, 4 insertions, 1 deletions

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 31d6afe92594..ff86c558af4c 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -1507,6 +1507,9 @@ do {					\
                 divisor = nsec * frequency;
         }
 
+        if (!divisor)
+                return dividend;
+
         return div64_u64(dividend, divisor);
 }
 
@@ -1529,7 +1532,7 @@ static int perf_event_start(struct perf_event *event)
 static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count)
 {
         struct hw_perf_event *hwc = &event->hw;
-        u64 period, sample_period;
+        s64 period, sample_period;
         s64 delta;
 
         period = perf_calculate_period(event, nsec, count);