Re: [PATCH v2] Input: sidewinder - use scnprintf() for the port names

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential
issue to consider:
- [High] Input: sidewinder - 64-bit division in sw_3dp_id() breaks
  32-bit builds
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commit 126f9830817fff924c0c3fe1b867c22b8b4a2692
Author: xujiahao <xujiahao@cmss.chinamobile.com>

Input: sidewinder - use scnprintf() for the port names

This commit switches sw_3dp_id() and sw_connect() from snprintf() to
scnprintf() to silence -Wformat-truncation warnings.

Link: https://lore.kernel.org/all/20261106033300.3439313-1-xujiahao@cmss.chinamobile.com/

> diff --git a/drivers/input/joystick/sidewinder.c b/drivers/input/joystick/sidewinder.c
> index 7f37d18c8477a..bca81df19da44 100644
> --- a/drivers/input/joystick/sidewinder.c
> +++ b/drivers/input/joystick/sidewinder.c
> @@ -535,12 +535,12 @@ static void sw_3dp_id(unsigned char *buf, char *comment, size_t size)
>  
>  	pnp[7] = rev[8] = 0;
>  
> -	snprintf(comment, size, " [PnP %d.%02d id %s rev %s]",
> -		(int) ((sw_get_bits(buf, 8, 6, 1) << 6) |		/* Two 6-bit values */
> -			sw_get_bits(buf, 16, 6, 1)) / 100,
> -		(int) ((sw_get_bits(buf, 8, 6, 1) << 6) |
> -			sw_get_bits(buf, 16, 6, 1)) % 100,
> -		 pnp, rev);
> +	scnprintf(comment, size, " [PnP %d.%02d id %s rev %s]",
> +		  (int)(((sw_get_bits(buf, 8, 6, 1) << 6) |	/* Two 6-bit values */
> +			  sw_get_bits(buf, 16, 6, 1)) / 100),
> +		  (int)(((sw_get_bits(buf, 8, 6, 1) << 6) |
> +			  sw_get_bits(buf, 16, 6, 1)) % 100),
> +		  pnp, rev);
>  }

[Severity: High]
Does wrapping `/ 100` and `% 100` inside the `(int)` cast break the build on
32-bit architectures?

sw_get_bits() returns `__u64`.  Previously, the `(int)` cast truncated the
bitwise OR result before dividing by 100, whereas moving the outer
parentheses around `/ 100` and `% 100` turns them into 64-bit unsigned
division and modulo, emitting undefined references to `__udivdi3` and
`__umoddi3` (or `__aeabi_uldivmod`) at link time on 32-bit targets.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261109010548.438699-1-xujiahao@cmss.chinamobile.com?part=1