[PATCH 01/18] drm/amd/display: improve the message printed when loading DC

[Harshit Mogalapalli]

Hi,

On 17/05/23 5:07 pm, Tom Chung wrote:
> From: Aurabindo Pillai <aurabindo.pillai at amd.com>
> 
> [Why&How]
> Change how DC version and hardware version is printed when driver is
> loaded.
> 
> - Remove exclamation
> - Add DC version and hardware version to both success and failure cases
> - Add version in between appropriate filler words to make a complete
>    statement.
> 
> Reviewed-by: Harry Wentland <harry.wentland at amd.com>
> Acked-by: Tom Chung <chiahsuan.chung at amd.com>
> Signed-off-by: Aurabindo Pillai <aurabindo.pillai at amd.com>
> ---
>   drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index 14b296e1d0f6..45b778631430 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -1666,10 +1666,11 @@ static int amdgpu_dm_init(struct amdgpu_device *adev)
>   	adev->dm.dc = dc_create(&init_data);
>   
>   	if (adev->dm.dc) {

	// Check for NULL
> -		DRM_INFO("Display Core initialized with v%s! %s\n", DC_VER,
> +		DRM_INFO("Display Core v%s initialized on %s\n", DC_VER,
>   			 dce_version_to_string(adev->dm.dc->ctx->dce_version));
>   	} else {
	// adev->dm.dc is NULL here

> -		DRM_INFO("Display Core failed to initialize with v%s!\n", DC_VER);
> +		DRM_INFO("Display Core v%s failed to initialize on %s\n", DC_VER,
> +			 dce_version_to_string(adev->dm.dc->ctx->dce_version));						       ^^^^NULL deref bug here.

I found this using static analysis with smatch.

drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm.c:1673 
amdgpu_dm_init() error: we previously assumed 'adev->dm.dc' could be 
null (see line 1669)

If you fix this could you please consider adding:

Reported-by: Harshit Mogalapalli <harshit.m.mogalapalli at oracle.com>

Thanks,
Harshit
														
					
>   		goto error;
>   	}
>