Testing with a gcc-7 snapshot produced an internal compiler error for this file:
drivers/tty/nozomi.c: In function 'receive_flow_control': drivers/tty/nozomi.c:919:12: internal compiler error: in get_substring_ranges_for_loc, at input.c:1388 static int receive_flow_control(struct nozomi *dc) I've reported this at https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78569 but also noticed that the code line contains a stack overflow, as it prints a string into a slightly shorter fixed-length 'tmp' variable. I don't see any point in the temporary variable, we can simply use pr_debug() to print the output directly. This change should not change any of the output but avoids both the stack overflow and the gcc crash. The stack overflow will not happen unless a module load parameter is also set to enable the debug messages. Signed-off-by: Arnd Bergmann <[email protected]> --- I'm posting two versions of the same fix, please choose one or the other as you see fit. --- drivers/tty/nozomi.c | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-) diff --git a/drivers/tty/nozomi.c b/drivers/tty/nozomi.c index e2020a691058..b17dbfd4f313 100644 --- a/drivers/tty/nozomi.c +++ b/drivers/tty/nozomi.c @@ -68,14 +68,8 @@ /* Default debug printout level */ #define NOZOMI_DEBUG_LEVEL 0x00 -#define P_BUF_SIZE 128 -#define NFO(_err_flag_, args...) \ -do { \ - char tmp[P_BUF_SIZE]; \ - snprintf(tmp, sizeof(tmp), ##args); \ - printk(_err_flag_ "[%d] %s(): %s\n", __LINE__, \ - __func__, tmp); \ -} while (0) +#define NFO(fmt, args...) \ + pr_debug("[%d] %s(): " fmt "\n", __LINE__, __func__, ##args); #define DBG1(args...) D_(0x01, ##args) #define DBG2(args...) D_(0x02, ##args) @@ -91,7 +85,7 @@ do { \ static int debug = NOZOMI_DEBUG_LEVEL; #define D(lvl, args...) do \ - {if (lvl & debug) NFO(KERN_DEBUG, ##args); } \ + {if (lvl & debug) NFO(args); } \ while (0) #define D_(lvl, args...) D(lvl, ##args) -- 2.9.0
