[bug report] drm/amdgpu : Generate XGMI topology info from driver level

[Dan Carpenter]

Hello Shaoyun Liu,

The patch fb30fc59a245: "drm/amdgpu : Generate XGMI topology info
from driver level" from Jun 27, 2018, leads to the following static
checker warning:

	drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.c:117 amdgpu_xgmi_add_device()
	warn: missing error code here? 'amdgpu_get_xgmi_hive()' failed. 'ret' = '0'

drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.c
    88 int amdgpu_xgmi_add_device(struct amdgpu_device *adev)
    89 {
    90 	struct psp_xgmi_topology_info *hive_topology;
    91 	struct amdgpu_hive_info *hive;
    92 	struct amdgpu_xgmi	*entry;
    93 	struct amdgpu_device *tmp_adev = NULL;
    94 
    95 	int count = 0, ret = -EINVAL;
    96 
    97 	if (!adev->gmc.xgmi.supported)
    98 		return 0;
    99 
    100 	ret = psp_xgmi_get_node_id(&adev->psp, &adev->gmc.xgmi.node_id);
    101 	if (ret) {
    102 		dev_err(adev->dev,
    103 			"XGMI: Failed to get node id\n");
    104 		return ret;
    105 	}
    106 
    107 	ret = psp_xgmi_get_hive_id(&adev->psp, &adev->gmc.xgmi.hive_id);
    108 	if (ret) {
    109 		dev_err(adev->dev,
    110 			"XGMI: Failed to get hive id\n");
    111 		return ret;
    112 	}
    113 
    114 	mutex_lock(&xgmi_mutex);
    115 	hive = amdgpu_get_xgmi_hive(adev);
    116 	if (!hive)
--> 117 		goto exit;

It does look like we should set "ret = -ESOMETHING;"...  Not sure what.

    118 
    119 	hive_topology = &hive->topology_info;
    120 
    121 	list_add_tail(&adev->gmc.xgmi.head, &hive->device_list);
    122 	list_for_each_entry(entry, &hive->device_list, head)
    123 		hive_topology->nodes[count++].node_id = entry->node_id;
    124 	hive->number_devices = count;
    125 
    126 	/* Each psp need to get the latest topology */
    127 	list_for_each_entry(tmp_adev, &hive->device_list, gmc.xgmi.head) {
    128 		ret = psp_xgmi_get_topology_info(&tmp_adev->psp, count, hive_topology);
    129 		if (ret) {
    130 			dev_err(tmp_adev->dev,
    131 				"XGMI: Get topology failure on device %llx, hive %llx, ret %d",
    132 				tmp_adev->gmc.xgmi.node_id,
    133 				tmp_adev->gmc.xgmi.hive_id, ret);
    134 			/* To do : continue with some node failed or disable the whole hive */
    135 			break;
    136 		}
    137 	}
    138 
    139 	list_for_each_entry(tmp_adev, &hive->device_list, gmc.xgmi.head) {
    140 		ret = amdgpu_xgmi_update_topology(hive, tmp_adev);
    141 		if (ret)
    142 			break;
    143 	}
    144 
    145 exit:
    146          mutex_unlock(&xgmi_mutex);
    147          return ret;
    148  }

regards,
dan carpenter