tracing: Clear parser->idx if only spaces are read

If only spaces were read while parsing the next string, then parser->idx should be
cleared in order to make trace_parser_loaded() return false.

Link: http://lkml.kernel.org/r/1516093350-12045-3-git-send-email-changbin.du@intel.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index c00a31d18f8a..cb90435e63da 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1236,14 +1236,14 @@ int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
                         cnt--;
                 }
 
+                parser->idx = 0;
+
                 /* only spaces were written */
                 if (isspace(ch) || !ch) {
                         *ppos += read;
                         ret = read;
                         goto out;
                 }
-
-                parser->idx = 0;
         }
 
         /* read the non-space input */