[PATCH 1/2] dynamic_debug: fix boot parameters parse

From: Peter Chen
Date: Tue Oct 27 2015 - 03:42:06 EST


The parse_args will delete space between boot parameters, so
if we add dyndbg="file drivers/usb/* +p" at bootargs, the parse_args
will split it as three parameters, and only "file" is for dyndbg,
then below error will occur at ddebug, it causes all non-module
ddebug fail during the boot process.

===============================================================
dynamic_debug:ddebug_parse_flags: bad flag-op f, at start of file
dynamic_debug:ddebug_exec_query: flags parse failed
===============================================================

As a solution, we can use comma to split parameters for ddebug booting
parameter, and replace comma with space at code, in that case, the ddebug
core can handle it with the same way we do it for /sys.

Signed-off-by: Peter Chen <peter.chen@xxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
---
lib/dynamic_debug.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index e491e02..da4883b 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -880,6 +880,8 @@ static int ddebug_dyndbg_param_cb(char *param, char *val,
if (strcmp(param, "dyndbg"))
return on_err; /* determined by caller */

+ /* relace comma with space */
+ strreplace(val, ',', ' ');
ddebug_exec_queries((val ? val : "+p"), modname);

return 0; /* query failure shouldnt stop module load */
--
1.9.1

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