[PATCH 01/22] drm/amdgpu: fix dereference after null check

[Christian König]

Am 10.05.24 um 04:50 schrieb Jesse Zhang:
> check the pointer hive before use.
>
> Signed-off-by: Jesse Zhang <Jesse.Zhang at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index 77f6fd50002a..00fe3c2d5431 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -5725,7 +5725,7 @@ int amdgpu_device_gpu_recover(struct amdgpu_device *adev,
>   	 * to put adev in the 1st position.
>   	 */
>   	INIT_LIST_HEAD(&device_list);
> -	if (!amdgpu_sriov_vf(adev) && (adev->gmc.xgmi.num_physical_nodes > 1)) {
> +	if (!amdgpu_sriov_vf(adev) && (adev->gmc.xgmi.num_physical_nodes > 1) && hive) {

That solution looks not optimal to me.

Checking adev->gmc.xgmi.num_physical_nodes > 1 already makes sure that 
hive shouldn't be NULL.

If automated checkers complain about that we should probably drop the 
adev->gmc.xgmi.num_physical_nodes > 1 check and check for hive instead.

Regards,
Christian.

>   		list_for_each_entry(tmp_adev, &hive->device_list, gmc.xgmi.head) {
>   			list_add_tail(&tmp_adev->reset_list, &device_list);
>   			if (adev->shutdown)