Re: [PATCH v2 2/2] drm/amdgpu: Fix the uninitialized variable warning

["Lazar, Lijo" <lijo.lazar@amd.com>]

On 4/25/2024 3:30 PM, Ma Jun wrote:
> Initialize the phy_id to 0 to fix the warning of
> "Using uninitialized value phy_id"
> 
> Signed-off-by: Ma Jun <Jun.Ma2@amd.com>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c
> index 8ed0e073656f..53d85fafd8ab 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c
> @@ -95,7 +95,7 @@ static ssize_t amdgpu_securedisplay_debugfs_write(struct file *f, const char __u
>  	struct psp_context *psp = &adev->psp;
>  	struct ta_securedisplay_cmd *securedisplay_cmd;
>  	struct drm_device *dev = adev_to_drm(adev);
> -	uint32_t phy_id;
> +	uint32_t phy_id = 0;
>  	uint32_t op;
>  	char str[64];
>  	int ret;
> @@ -135,6 +135,10 @@ static ssize_t amdgpu_securedisplay_debugfs_write(struct file *f, const char __u
>  		mutex_unlock(&psp->securedisplay_context.mutex);
>  		break;
>  	case 2:
> +		if (size < 3) {
> +			dev_err(adev->dev, "Invalid input: %s\n", str);
> +			return -EINVAL;
> +		}

Better is to check the return of sscanf to see if phy_id value is
successfully scanned. Otherwise, return error.

Thanks,
Lijo

>  		mutex_lock(&psp->securedisplay_context.mutex);
>  		psp_prep_securedisplay_cmd_buf(psp, &securedisplay_cmd,
>  			TA_SECUREDISPLAY_COMMAND__SEND_ROI_CRC);