Free before setting NULL to prevent memory leak

1 files changed, 3 insertions, 1 deletions

diff --git a/litmus/trace.c b/litmus/trace.c
index 6b3e5f77cc5e..330d1e8240be 100644
--- a/litmus/trace.c
+++ b/litmus/trace.c
@@ -425,11 +425,13 @@ static int alloc_timestamp_buffer(struct ftdev* ftdev, unsigned int idx)
 
 static void free_timestamp_buffer(struct ftdev* ftdev, unsigned int idx)
 {
+        struct ft_buffer* tmp = ftdev->minor[idx].buf;
+        smp_rmb();
         ftdev->minor[idx].buf = NULL;
         /* Make sure all cores have actually seen buf == NULL before
          * yanking out the mappings from underneath them. */
         smp_wmb();
-        free_ft_buffer(ftdev->minor[idx].buf);
+        free_ft_buffer(tmp);
 }
 
 static ssize_t write_timestamp_from_user(struct ft_buffer* buf, size_t len,