[PATCH] drm/amdgpu: address the static checker warnings

[Dan Carpenter]

On Fri, Apr 24, 2020 at 06:41:15PM +0800, Evan Quan wrote:
> drivers/gpu/drm/amd/amdgpu/amdgpu_device.c:4199 amdgpu_device_gpu_recover()
> error: we previously assumed 'hive' could be null (see line 4196)
> 
> This is introduced by "drm/amdgpu: optimize the gpu reset for XGMI setup V2".
> 
> Change-Id: I9c22b57abc9f512114112f93fb035f1fecf26beb
> Signed-off-by: Evan Quan <evan.quan at amd.com>
> Reported-by: Dan Carpenter <dan.carpenter at oracle.com>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index 71278942f9f0..898338dc9605 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -4274,7 +4274,8 @@ int amdgpu_device_gpu_recover(struct amdgpu_device *adev,
>  		if (!amdgpu_device_lock_adev(tmp_adev, !hive)) {
>  			DRM_INFO("Bailing on TDR for s_job:%llx, as another already in progress",
>  				  job ? job->base.id : -1);
> -			mutex_unlock(&hive->hive_lock);
> +			if (hive)
> +				mutex_unlock(&hive->hive_lock);

In the current code, we know for a fact that "hive" is NULL at this
point.  Presumably this will be changed in the future?  Otherwise why
not just delete the mutex_unlock() because it is dead code.

regards,
dan carpenter