Subject: Re: linux-next: build warning after merge of the kspp tree

From: Stephen Rothwell <[email-masked]>
Date: Mon, 6 Sep 2021 15:41:51 +1000

Hi all,

On Mon, 30 Aug 2021 18:44:29 +1000 Stephen Rothwell <[email-masked]> wrote:
>
> After merging the kspp tree, today's linux-next build (powerpc
> allyesconfig) produced this warning:
> 
> drivers/gpu/drm/kmb/kmb_plane.c:135:20: warning: array subscript 3 is above array bounds of 'struct layer_status[1]' [-Warray-bounds]
>   135 |   kmb->plane_status[plane_id].ctrl = LCD_CTRL_GL2_ENABLE;
>       |   ~~~~~~~~~~~~~~~~~^~~~~~~~~~
> In file included from drivers/gpu/drm/kmb/kmb_plane.c:17:
> drivers/gpu/drm/kmb/kmb_drv.h:48:23: note: while referencing 'plane_status'
>    48 |  struct layer_status  plane_status[KMB_MAX_PLANES];
>       |                       ^~~~~~~~~~~~
> drivers/gpu/drm/kmb/kmb_plane.c:132:20: warning: array subscript 2 is above array bounds of 'struct layer_status[1]' [-Warray-bounds]
>   132 |   kmb->plane_status[plane_id].ctrl = LCD_CTRL_GL1_ENABLE;
>       |   ~~~~~~~~~~~~~~~~~^~~~~~~~~~
> In file included from drivers/gpu/drm/kmb/kmb_plane.c:17:
> drivers/gpu/drm/kmb/kmb_drv.h:48:23: note: while referencing 'plane_status'
>    48 |  struct layer_status  plane_status[KMB_MAX_PLANES];
>       |                       ^~~~~~~~~~~~
> drivers/gpu/drm/kmb/kmb_plane.c:129:20: warning: array subscript 1 is above array bounds of 'struct layer_status[1]' [-Warray-bounds]
>   129 |   kmb->plane_status[plane_id].ctrl = LCD_CTRL_VL2_ENABLE;
>       |   ~~~~~~~~~~~~~~~~~^~~~~~~~~~
> In file included from drivers/gpu/drm/kmb/kmb_plane.c:17:
> drivers/gpu/drm/kmb/kmb_drv.h:48:23: note: while referencing 'plane_status'
>    48 |  struct layer_status  plane_status[KMB_MAX_PLANES];
>       |                       ^~~~~~~~~~~~
> 
> Exposed by commit
> 
>   656256c0d67c ("Makefile: Enable -Warray-bounds")
> 
> Introduced by commit
> 
>   7f7b96a8a0a1 ("drm/kmb: Add support for KeemBay Display")
> 
> from v5.11-rc1.

Due to Linus -Werror, these are now errors :-(

I have reverted commit 656256c0d67c for now.
-- 
Cheers,
Stephen Rothwell