Re: [PATCH] drm/bridge: Constify struct i2c_device_id

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Christophe,

On Wed, Nov 13, 2024 at 10:19:24PM +0100, Christophe JAILLET wrote:
> Le 12/11/2024 à 23:43, Laurent Pinchart a écrit :
> > On Tue, Nov 12, 2024 at 10:12:25PM +0100, Christophe JAILLET wrote:
> >> 'struct i2c_device_id' is not modified in these drivers.
> >>
> >> Constifying this structure moves some data to a read-only section, so
> >> increase overall security.
> >>
> >> On a x86_64, with allmodconfig, as an example:
> >> Before:
> >> ======
> >>     text	   data	    bss	    dec	    hex	filename
> >>    15566	    987	     32	  16585	   40c9	drivers/gpu/drm/bridge/chipone-icn6211.o
> >>
> >> After:
> >> =====
> >>     text	   data	    bss	    dec	    hex	filename
> >>    15630	    923	     32	  16585	   40c9	drivers/gpu/drm/bridge/chipone-icn6211.o
> >>
> >> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> >> ---
> >> Compile tested-only.
> >> ---
> >>   drivers/gpu/drm/bridge/chipone-icn6211.c   | 2 +-
> >>   drivers/gpu/drm/bridge/lontium-lt9211.c    | 2 +-
> >>   drivers/gpu/drm/bridge/lontium-lt9611.c    | 2 +-
> >>   drivers/gpu/drm/bridge/lontium-lt9611uxc.c | 2 +-
> >>   drivers/gpu/drm/bridge/ti-sn65dsi83.c      | 2 +-
> >>   drivers/gpu/drm/bridge/ti-sn65dsi86.c      | 2 +-
> > 
> > While at it, could you address drivers/gpu/drm/i2c/tda9950.c too ? If I
> > were to push a tad more, there are only two other drivers in the kernel
> > with the same issues outside of drivers/gpu/ according to
> 
> Hi Laurent,
> 
> this is in my todo list. I wanted to send it separately because all 
> these files are in gpu/drm/bridge/ and tda9950.c is in gpu/drm/.
> 
> Most of the times, maintainers ask for separate patches when several 
> drivers are patched. For such clean-ups, I try at least to group them by 
> directory.

I would probably have included tda9950.c in this patch, but I'm also
fine handling it separately.

> Same answer the other files in input and sound. Patches will be sent in 
> a few days.

Thank you. If you have extra time, there are also a handful of similar
issues with of_device_id :-)

> I've also sent one for the documentation [1] and will send one for 
> const_structs.checkpatch as well.

Thank you for that.

> CJ
> 
> [1]: https://lore.kernel.org/linux-kernel/c8e6da4adb7381ee27e8e11854c9d856382cdc93.1731445244.git.christophe.jaillet@wanadoo.fr/
> 
> > $ git grep '^static struct i2c_device_id'
> > drivers/gpu/drm/bridge/chipone-icn6211.c:static struct i2c_device_id chipone_i2c_id[] = {
> > drivers/gpu/drm/bridge/lontium-lt9211.c:static struct i2c_device_id lt9211_id[] = {
> > drivers/gpu/drm/bridge/lontium-lt9611.c:static struct i2c_device_id lt9611_id[] = {
> > drivers/gpu/drm/bridge/lontium-lt9611uxc.c:static struct i2c_device_id lt9611uxc_id[] = {
> > drivers/gpu/drm/bridge/ti-sn65dsi83.c:static struct i2c_device_id sn65dsi83_id[] = {
> > drivers/gpu/drm/bridge/ti-sn65dsi86.c:static struct i2c_device_id ti_sn65dsi86_id[] = {
> > drivers/gpu/drm/i2c/tda9950.c:static struct i2c_device_id tda9950_ids[] = {
> > drivers/input/keyboard/cypress-sf.c:static struct i2c_device_id cypress_sf_id_table[] = {
> > sound/soc/codecs/cs42l51-i2c.c:static struct i2c_device_id cs42l51_i2c_id[] = {
> > 
> > :-)
> > 
> > Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
> > 
> >>   6 files changed, 6 insertions(+), 6 deletions(-)

-- 
Regards,

Laurent Pinchart