[PATCH] platform/x86: thinkpad_acpi: Fix uninitialized symbol

[PATCH] platform/x86: thinkpad_acpi: Fix uninitialized symbol

[Matthias Fetzer]

When the TPACPI_FAN_WR_ACPI_FANW branch is taken s stays uninitialized
and would be later used in a debug print.

Since the registers are always set to the same two static values inside the
branch s is initialized to 0.

Signed-off-by: Matthias Fetzer <kontakt@matthias-fetzer.de>
---
 drivers/platform/x86/thinkpad_acpi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index 8f7053920884..4c1b0553f872 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -8318,7 +8318,7 @@ static int fan_set_level_safe(int level)
 
 static int fan_set_enable(void)
 {
-	u8 s;
+	u8 s = 0;
 	int rc;
 
 	if (!fan_control_allowed)
-- 
2.46.0

Re: [PATCH] platform/x86: thinkpad_acpi: Fix uninitialized symbol

[Hans de Goede]

Hi,

On 9/3/24 7:27 PM, Matthias Fetzer wrote:
> When the TPACPI_FAN_WR_ACPI_FANW branch is taken s stays uninitialized
> and would be later used in a debug print.
> 
> Since the registers are always set to the same two static values inside the
> branch s is initialized to 0.
> 
> Signed-off-by: Matthias Fetzer <kontakt@matthias-fetzer.de>

Thank you.

I've applied this with the following tags added to the commit message:

Fixes: 57d0557dfa49 ("platform/x86: thinkpad_acpi: Add Thinkpad Edge E531 fan support")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/platform-driver-x86/f99e558d-c62a-41eb-93b3-cf00c016d907@stanley.mountain/

Thank you for your patch, I've applied this patch to my review-hans 
branch:
https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86.git/log/?h=review-hans

Note it will show up in my review-hans branch once I've pushed my
local branch there, which might take a while.

Once I've run some tests on this branch the patches there will be
added to the platform-drivers-x86/for-next branch and eventually
will be included in the pdx86 pull-request to Linus for the next
merge-window.

Regards,

Hans



> ---
>  drivers/platform/x86/thinkpad_acpi.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
> index 8f7053920884..4c1b0553f872 100644
> --- a/drivers/platform/x86/thinkpad_acpi.c
> +++ b/drivers/platform/x86/thinkpad_acpi.c
> @@ -8318,7 +8318,7 @@ static int fan_set_level_safe(int level)
>  
>  static int fan_set_enable(void)
>  {
> -	u8 s;
> +	u8 s = 0;
>  	int rc;
>  
>  	if (!fan_control_allowed)