Nouveau - Aug 2020 - [PATCH AUTOSEL 4.14 08/22] drm/nouveau: fix multiple instances of reference count leaks

From: Aditya Pakki <pakki001 at umn.edu>

[ Upstream commit 659fb5f154c3434c90a34586f3b7aa1c39cf6062 ]

On calling pm_runtime_get_sync() the reference count of the device
is incremented. In case of failure, decrement the
ref count before returning the error.

Signed-off-by: Aditya Pakki <pakki001 at umn.edu>
Signed-off-by: Ben Skeggs <bskeggs at redhat.com>
Signed-off-by: Sasha Levin <sashal at kernel.org>
---
 drivers/gpu/drm/nouveau/nouveau_drm.c | 8 ++++++--
 drivers/gpu/drm/nouveau/nouveau_gem.c | 4 +++-
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c
b/drivers/gpu/drm/nouveau/nouveau_drm.c
index d00524a5d7f08..fb6b1d0f7fef3 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_drm.c
@@ -840,8 +840,10 @@ nouveau_drm_open(struct drm_device *dev, struct drm_file
*fpriv)
 
 	/* need to bring up power immediately if opening device */
 	ret = pm_runtime_get_sync(dev->dev);
-	if (ret < 0 && ret != -EACCES)
+	if (ret < 0 && ret != -EACCES) {
+		pm_runtime_put_autosuspend(dev->dev);
 		return ret;
+	}
 
 	get_task_comm(tmpname, current);
 	snprintf(name, sizeof(name), "%s[%d]", tmpname,
pid_nr(fpriv->pid));
@@ -930,8 +932,10 @@ nouveau_drm_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
 	long ret;
 
 	ret = pm_runtime_get_sync(dev->dev);
-	if (ret < 0 && ret != -EACCES)
+	if (ret < 0 && ret != -EACCES) {
+		pm_runtime_put_autosuspend(dev->dev);
 		return ret;
+	}
 
 	switch (_IOC_NR(cmd) - DRM_COMMAND_BASE) {
 	case DRM_NOUVEAU_NVIF:
diff --git a/drivers/gpu/drm/nouveau/nouveau_gem.c
b/drivers/gpu/drm/nouveau/nouveau_gem.c
index 60ffb70bb9089..c6149b5be073e 100644
--- a/drivers/gpu/drm/nouveau/nouveau_gem.c
+++ b/drivers/gpu/drm/nouveau/nouveau_gem.c
@@ -42,8 +42,10 @@ nouveau_gem_object_del(struct drm_gem_object *gem)
 	int ret;
 
 	ret = pm_runtime_get_sync(dev);
-	if (WARN_ON(ret < 0 && ret != -EACCES))
+	if (WARN_ON(ret < 0 && ret != -EACCES)) {
+		pm_runtime_put_autosuspend(dev);
 		return;
+	}
 
 	if (gem->import_attach)
 		drm_prime_gem_destroy(gem, nvbo->bo.sg);
-- 
2.25.1