[PATCH] drm/amdgpu: fix null pointer reference to adev.

[Christian König]

Am 07.07.20 um 05:26 schrieb Lepton Wu:
> I hit this when compiling amdgpu in kernel. amdgpu_driver_load_kms fail
> to load firmwares since GPU was initialized before rootfs is ready.
> Just gracefully fail in such cases.

Good catch, but the solution looks incorrect to me.

The underlying problem is that the return value of 
amdgpu_driver_load_kms() is not correctly checked.

Christian.


>
> Signed-off-by: Lepton Wu <ytht.net at gmail.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 3 ++-
>   drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 2 ++
>   2 files changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> index 126e74758a34..f9d277f8ddd4 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> @@ -1124,7 +1124,8 @@ static int amdgpu_pci_probe(struct pci_dev *pdev,
>   		goto err_pci;
>   
>   	adev = dev->dev_private;
> -	ret = amdgpu_debugfs_init(adev);
> +	if (adev)
> +		ret = amdgpu_debugfs_init(adev);
>   	if (ret)
>   		DRM_ERROR("Creating debugfs files failed (%d).\n", ret);
>   
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> index d7e17e34fee1..99a6ec49ead5 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> @@ -978,6 +978,8 @@ int amdgpu_driver_open_kms(struct drm_device *dev, struct drm_file *file_priv)
>   	struct amdgpu_fpriv *fpriv;
>   	int r, pasid;
>   
> +	if (!adev)
> +		return -ENODEV;
>   	/* Ensure IB tests are run on ring */
>   	flush_delayed_work(&adev->delayed_init_work);
>