drm/nouveau: platform: Fix deferred probe

The error cleanup paths aren't quite correct and will crash upon
deferred probe.

Cc: stable@vger.kernel.org # v4.3+
Reviewed-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

2 files changed, 30 insertions, 12 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_platform.c b/drivers/gpu/drm/nouveau/nouveau_platform.c
index 8a70cec59bcd..2dfe58af12e4 100644
--- a/drivers/gpu/drm/nouveau/nouveau_platform.c
+++ b/drivers/gpu/drm/nouveau/nouveau_platform.c
@@ -24,7 +24,7 @@
 static int nouveau_platform_probe(struct platform_device *pdev)
 {
         const struct nvkm_device_tegra_func *func;
-        struct nvkm_device *device;
+        struct nvkm_device *device = NULL;
         struct drm_device *drm;
         int ret;
 
diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/device/tegra.c b/drivers/gpu/drm/nouveau/nvkm/engine/device/tegra.c
index 7f8a42721eb2..e7e581d6a8ff 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/device/tegra.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/device/tegra.c
@@ -252,32 +252,40 @@ nvkm_device_tegra_new(const struct nvkm_device_tegra_func *func,
 
         if (!(tdev = kzalloc(sizeof(*tdev), GFP_KERNEL)))
                 return -ENOMEM;
-        *pdevice = &tdev->device;
+
         tdev->func = func;
         tdev->pdev = pdev;
         tdev->irq = -1;
 
         tdev->vdd = devm_regulator_get(&pdev->dev, "vdd");
-        if (IS_ERR(tdev->vdd))
-                return PTR_ERR(tdev->vdd);
+        if (IS_ERR(tdev->vdd)) {
+                ret = PTR_ERR(tdev->vdd);
+                goto free;
+        }
 
         tdev->rst = devm_reset_control_get(&pdev->dev, "gpu");
-        if (IS_ERR(tdev->rst))
-                return PTR_ERR(tdev->rst);
+        if (IS_ERR(tdev->rst)) {
+                ret = PTR_ERR(tdev->rst);
+                goto free;
+        }
 
         tdev->clk = devm_clk_get(&pdev->dev, "gpu");
-        if (IS_ERR(tdev->clk))
-                return PTR_ERR(tdev->clk);
+        if (IS_ERR(tdev->clk)) {
+                ret = PTR_ERR(tdev->clk);
+                goto free;
+        }
 
         tdev->clk_pwr = devm_clk_get(&pdev->dev, "pwr");
-        if (IS_ERR(tdev->clk_pwr))
-                return PTR_ERR(tdev->clk_pwr);
+        if (IS_ERR(tdev->clk_pwr)) {
+                ret = PTR_ERR(tdev->clk_pwr);
+                goto free;
+        }
 
         nvkm_device_tegra_probe_iommu(tdev);
 
         ret = nvkm_device_tegra_power_up(tdev);
         if (ret)
-                return ret;
+                goto remove;
 
         tdev->gpu_speedo = tegra_sku_info.gpu_speedo_value;
         ret = nvkm_device_ctor(&nvkm_device_tegra_func, NULL, &pdev->dev,
@@ -285,9 +293,19 @@ nvkm_device_tegra_new(const struct nvkm_device_tegra_func *func,
                                cfg, dbg, detect, mmio, subdev_mask,
                                &tdev->device);
         if (ret)
-                return ret;
+                goto powerdown;
+
+        *pdevice = &tdev->device;
 
         return 0;
+
+powerdown:
+        nvkm_device_tegra_power_down(tdev);
+remove:
+        nvkm_device_tegra_remove_iommu(tdev);
+free:
+        kfree(tdev);
+        return ret;
 }
 #else
 int