| Message ID | 3f4be7a99933cf8566e630da54f6ab913caac432.1695453322.git.christophe.jaillet@wanadoo.fr |
|---|---|
| State | New |
| Headers | show |
| Series | leds: trigger: ledtrig-cpu:: Fix a warning when compiling with W=1 | expand |
On Sat, 23 Sep 2023 09:15:38 +0200, Christophe JAILLET wrote: > In order to teach the compiler that 'trig->name' will never be truncated, > we need to tell it that 'cpu' is not negative. > > When building with W=1, this fixes the following warnings: > > drivers/leds/trigger/ledtrig-cpu.c: In function ‘ledtrig_cpu_init’: > drivers/leds/trigger/ledtrig-cpu.c:155:56: error: ‘%d’ directive output may be truncated writing between 1 and 11 bytes into a region of size 5 [-Werror=format-truncation=] > 155 | snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu); > | ^~ > drivers/leds/trigger/ledtrig-cpu.c:155:52: note: directive argument in the range [-2147483648, 7] > 155 | snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu); > | ^~~~~~~ > drivers/leds/trigger/ledtrig-cpu.c:155:17: note: ‘snprintf’ output between 5 and 15 bytes into a destination of size 8 > 155 | snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu); > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > [...] Applied, thanks! [1/1] leds: trigger: ledtrig-cpu:: Fix a warning when compiling with W=1 commit: 5272d74b29929c8395720a7e35971a4f0fb6783d -- Lee Jones [李琼斯]
On Sat, 23 Sep 2023, Christophe JAILLET wrote: > In order to teach the compiler that 'trig->name' will never be truncated, > we need to tell it that 'cpu' is not negative. > > When building with W=1, this fixes the following warnings: > > drivers/leds/trigger/ledtrig-cpu.c: In function ‘ledtrig_cpu_init’: > drivers/leds/trigger/ledtrig-cpu.c:155:56: error: ‘%d’ directive output may be truncated writing between 1 and 11 bytes into a region of size 5 [-Werror=format-truncation=] > 155 | snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu); > | ^~ > drivers/leds/trigger/ledtrig-cpu.c:155:52: note: directive argument in the range [-2147483648, 7] > 155 | snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu); > | ^~~~~~~ > drivers/leds/trigger/ledtrig-cpu.c:155:17: note: ‘snprintf’ output between 5 and 15 bytes into a destination of size 8 > 155 | snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu); > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > Fixes: 8f88731d052d ("led-triggers: create a trigger for CPU activity") > Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> > --- > drivers/leds/trigger/ledtrig-cpu.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) I made the subject line less generic and applied it, thanks.
diff --git a/drivers/leds/trigger/ledtrig-cpu.c b/drivers/leds/trigger/ledtrig-cpu.c index 8af4f9bb9cde..05848a2fecff 100644 --- a/drivers/leds/trigger/ledtrig-cpu.c +++ b/drivers/leds/trigger/ledtrig-cpu.c @@ -130,7 +130,7 @@ static int ledtrig_prepare_down_cpu(unsigned int cpu) static int __init ledtrig_cpu_init(void) { - int cpu; + unsigned int cpu; int ret; /* Supports up to 9999 cpu cores */ @@ -152,7 +152,7 @@ static int __init ledtrig_cpu_init(void) if (cpu >= 8) continue; - snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu); + snprintf(trig->name, MAX_NAME_LEN, "cpu%u", cpu); led_trigger_register_simple(trig->name, &trig->_trig); }
In order to teach the compiler that 'trig->name' will never be truncated, we need to tell it that 'cpu' is not negative. When building with W=1, this fixes the following warnings: drivers/leds/trigger/ledtrig-cpu.c: In function ‘ledtrig_cpu_init’: drivers/leds/trigger/ledtrig-cpu.c:155:56: error: ‘%d’ directive output may be truncated writing between 1 and 11 bytes into a region of size 5 [-Werror=format-truncation=] 155 | snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu); | ^~ drivers/leds/trigger/ledtrig-cpu.c:155:52: note: directive argument in the range [-2147483648, 7] 155 | snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu); | ^~~~~~~ drivers/leds/trigger/ledtrig-cpu.c:155:17: note: ‘snprintf’ output between 5 and 15 bytes into a destination of size 8 155 | snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fixes: 8f88731d052d ("led-triggers: create a trigger for CPU activity") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> --- drivers/leds/trigger/ledtrig-cpu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)