3.13.11-ckt34 -stable review patch. If anyone has any objections, please let me know.
---8<------------------------------------------------------------ From: Aaron Conole <[email protected]> commit fe22cd9b7c980b8b948ec85f034a8668c57ec867 upstream. Currently, pr_debug and pr_devel will not elide function call arguments appearing in calls to the no_printk for these macros. This is because all side effects must be honored before proceeding to the 0-value assignment in no_printk. The behavior is contrary to documentation found in the CodingStyle and the header file where these functions are declared. This patch corrects that behavior by shunting out the call to no_printk completely. The format string is still checked by gcc for correctness, but no code seems to be emitted in common cases. [[email protected]: remove braces, per Joe] Fixes: 5264f2f75d86 ("include/linux/printk.h: use and neaten no_printk") Signed-off-by: Aaron Conole <[email protected]> Reported-by: Dmitry Vyukov <[email protected]> Cc: Joe Perches <[email protected]> Cc: Jason Baron <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Kamal Mostafa <[email protected]> --- include/linux/printk.h | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/include/linux/printk.h b/include/linux/printk.h index 1864d94..152c2ca 100644 --- a/include/linux/printk.h +++ b/include/linux/printk.h @@ -89,13 +89,13 @@ struct va_format { /* * Dummy printk for disabled debugging statements to use whilst maintaining - * gcc's format and side-effect checking. + * gcc's format checking. */ -static inline __printf(1, 2) -int no_printk(const char *fmt, ...) -{ - return 0; -} +#define no_printk(fmt, ...) \ +do { \ + if (0) \ + printk(fmt, ##__VA_ARGS__); \ +} while (0) #ifdef CONFIG_EARLY_PRINTK extern asmlinkage __printf(1, 2) -- 1.9.1
