Re: [PATCH] staging: fbtft: Use sysfs_emit_at() to print to sysfs file

Andy Shevchenko <[email protected]> Wed, 3 Jun 2026 10:49:11 +0300

Newsgroups	org.kernel.vger.kernel-janitors,dev.linux.lists.linux-staging,org.freedesktop.lists.dri-devel,org.kernel.vger.linux-fbdev,org.kernel.vger.linux-kernel
Organization	Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo
Message-ID	<[email protected]>

On Wed, Jun 03, 2026 at 10:34:21AM +0300, Dan Carpenter wrote:
> This scnprintf() uses the wrong limit.  It should be "PAGE_SIZE - len"
> instead of just PAGE_SIZE.  We're not going to hit the limit in real
> life since we are printing at most FBTFT_GAMMA_MAX_VALUES_TOTAL (128)
> u32 values, however, it's still worth fixing.
> 
> Use sysfs_emit_at() to fix this since this is a sysfs file.

OK,
Reviewed-by: Andy Shevchenko <[email protected]>

...

>  	for (i = 0; i < par->gamma.num_curves; i++) {
>  		for (j = 0; j < par->gamma.num_values; j++)
> -			len += scnprintf(&buf[len], PAGE_SIZE,
> +			len += sysfs_emit_at(buf, len,
>  			     "%04x ", curves[i * par->gamma.num_values + j]);

Can we switch to use hex_dump_to_buffer() at some point?

-- 
With Best Regards,
Andy Shevchenko