[PATCH AUTOSEL 4.4 06/16] drm/nouveau: fix multiple instances of reference count leaks

From: Sasha Levin
Date: Mon Aug 10 2020 - 15:16:08 EST


From: Aditya Pakki <pakki001@xxxxxxx>

[ 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@xxxxxxx>
Signed-off-by: Ben Skeggs <bskeggs@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 91a61d2cca889..a90840e391100 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_drm.c
@@ -805,8 +805,10 @@ 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));
@@ -894,8 +896,10 @@ 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 ae560f5977fca..e5db2a385cb65 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