Re: [PATCH 17/18] x86_energy_perf_policy: Fix write_sysfs() return type

[Andy Shevchenko <andriy.shevchenko@intel.com>]

On Mon, Oct 19, 2026 at 12:43:38PM -0400, Len Brown wrote:

> write_sysfs() returns an unsigned int even though it returns -1 when
> write() fails. This converts the error to UINT_MAX and can cause callers
> that treat a nonzero return value as success to miss the failure.
> 
> Use ssize_t to match write(), update the receiving variable accordingly,
> and explicitly require a positive result in sysfs_write_string().

...

> static int sysfs_write_string(const char *path, const char *buf)

>  	len = snprintf(tmp, sizeof(tmp), "%s\n", buf);
>  	if (len < 0 || len >= (int)sizeof(tmp))
>  		return -1;
> -	return write_sysfs(path, tmp, (size_t)len + 1) ? 0 : -1;
> +	return write_sysfs(path, tmp, (size_t)len + 1) > 0 ? 0 : -1;

Wouldn't it be better (but I haven't checked callers of this) to have
other way around?

	int ret;
	...
	ret = write_sysfs(path, tmp, (size_t)len + 1);
	if (ret < 0)
		return ret;

	return 0;

>  }

-- 
With Best Regards,
Andy Shevchenko