diff --git a/drivers/gpu/drm/drm_pci.c b/drivers/gpu/drm/drm_pci.c
index e20f78b542a7..f5bd9e590c80 100644
--- a/drivers/gpu/drm/drm_pci.c
+++ b/drivers/gpu/drm/drm_pci.c
@@ -164,6 +164,8 @@ int drm_get_pci_dev(struct pci_dev *pdev, const struct pci_device_id *ent,
 	dev->hose = pdev->sysdata;
 #endif
 
+	mutex_lock(&drm_global_mutex);
+
 	if ((ret = drm_fill_in_dev(dev, ent, driver))) {
 		printk(KERN_ERR "DRM: Fill_in_dev failed.\n");
 		goto err_g2;
@@ -199,6 +201,7 @@ int drm_get_pci_dev(struct pci_dev *pdev, const struct pci_device_id *ent,
 		 driver->name, driver->major, driver->minor, driver->patchlevel,
 		 driver->date, pci_name(pdev), dev->primary->index);
 
+	mutex_unlock(&drm_global_mutex);
 	return 0;
 
 err_g4:
@@ -210,6 +213,7 @@ int drm_get_pci_dev(struct pci_dev *pdev, const struct pci_device_id *ent,
 	pci_disable_device(pdev);
 err_g1:
 	kfree(dev);
+	mutex_unlock(&drm_global_mutex);
 	return ret;
 }
 EXPORT_SYMBOL(drm_get_pci_dev);
diff --git a/drivers/gpu/drm/drm_platform.c b/drivers/gpu/drm/drm_platform.c
index 460e9a3afa8d..92d1d0fb7b75 100644
--- a/drivers/gpu/drm/drm_platform.c
+++ b/drivers/gpu/drm/drm_platform.c
@@ -53,6 +53,8 @@ int drm_get_platform_dev(struct platform_device *platdev,
 	dev->platformdev = platdev;
 	dev->dev = &platdev->dev;
 
+	mutex_lock(&drm_global_mutex);
+
 	ret = drm_fill_in_dev(dev, NULL, driver);
 
 	if (ret) {
@@ -87,6 +89,8 @@ int drm_get_platform_dev(struct platform_device *platdev,
 
 	list_add_tail(&dev->driver_item, &driver->device_list);
 
+	mutex_unlock(&drm_global_mutex);
+
 	DRM_INFO("Initialized %s %d.%d.%d %s on minor %d\n",
 		 driver->name, driver->major, driver->minor, driver->patchlevel,
 		 driver->date, dev->primary->index);
@@ -100,6 +104,7 @@ int drm_get_platform_dev(struct platform_device *platdev,
 		drm_put_minor(&dev->control);
 err_g1:
 	kfree(dev);
+	mutex_unlock(&drm_global_mutex);
 	return ret;
 }
 EXPORT_SYMBOL(drm_get_platform_dev);