Re: [PATCH] drm/msm/disp: fix endian bug in debugfs code

[abhinavk@codeaurora.org]

On 2021-10-04 06:47, Dan Carpenter wrote:
> The "vbif->features" is type unsigned long but the debugfs file
> is treating it as a u32 type.  This will work in little endian
> systems, but the correct thing is to change the debugfs to use
> an unsigned long.
> 
> Fixes: 25fdd5933e4c ("drm/msm: Add SDM845 DPU support")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Abhinav Kumar <abhinavk@codeaurora.org>
> ---
> You might wonder why this code has so many casts.  It's required 
> because
> this data is const.  Which is fine because the file is read only.
> 
>  drivers/gpu/drm/msm/disp/dpu1/dpu_vbif.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_vbif.c
> b/drivers/gpu/drm/msm/disp/dpu1/dpu_vbif.c
> index 21d20373eb8b..e645a886e3c6 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_vbif.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_vbif.c
> @@ -305,8 +305,8 @@ void dpu_debugfs_vbif_init(struct dpu_kms
> *dpu_kms, struct dentry *debugfs_root)
> 
>  		debugfs_vbif = debugfs_create_dir(vbif_name, entry);
> 
> -		debugfs_create_u32("features", 0600, debugfs_vbif,
> -			(u32 *)&vbif->features);
> +		debugfs_create_ulong("features", 0600, debugfs_vbif,
> +				     (unsigned long *)&vbif->features);
> 
>  		debugfs_create_u32("xin_halt_timeout", 0400, debugfs_vbif,
>  			(u32 *)&vbif->xin_halt_timeout);