[PATCH] drm/tegra: fix reference leak when pm_runtime_get_sync fails

[PATCH] drm/tegra: fix reference leak when pm_runtime_get_sync fails

[Qinglang Miao]

The PM reference count is not expected to be incremented on
return in these tegra functions.

However, pm_runtime_get_sync will increment the PM reference
count even failed. Forgetting to putting operation will result
in a reference leak here.

Replace it with pm_runtime_resume_and_get to keep usage
counter balanced.

Fixes: fd67e9c6ed5a ("drm/tegra: Do not implement runtime PM")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
---
 drivers/gpu/drm/tegra/dc.c   | 2 +-
 drivers/gpu/drm/tegra/dsi.c  | 2 +-
 drivers/gpu/drm/tegra/hdmi.c | 2 +-
 drivers/gpu/drm/tegra/hub.c  | 2 +-
 drivers/gpu/drm/tegra/sor.c  | 2 +-
 drivers/gpu/drm/tegra/vic.c  | 2 +-
 6 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c
index 424ad60b4..b2c8c68b7 100644
--- a/drivers/gpu/drm/tegra/dc.c
+++ b/drivers/gpu/drm/tegra/dc.c
@@ -2184,7 +2184,7 @@ static int tegra_dc_runtime_resume(struct host1x_client *client)
 	struct device *dev = client->dev;
 	int err;
 
-	err = pm_runtime_get_sync(dev);
+	err = pm_runtime_resume_and_get(dev);
 	if (err < 0) {
 		dev_err(dev, "failed to get runtime PM: %d\n", err);
 		return err;
diff --git a/drivers/gpu/drm/tegra/dsi.c b/drivers/gpu/drm/tegra/dsi.c
index 5691ef1b0..f46d377f0 100644
--- a/drivers/gpu/drm/tegra/dsi.c
+++ b/drivers/gpu/drm/tegra/dsi.c
@@ -1111,7 +1111,7 @@ static int tegra_dsi_runtime_resume(struct host1x_client *client)
 	struct device *dev = client->dev;
 	int err;
 
-	err = pm_runtime_get_sync(dev);
+	err = pm_runtime_resume_and_get(dev);
 	if (err < 0) {
 		dev_err(dev, "failed to get runtime PM: %d\n", err);
 		return err;
diff --git a/drivers/gpu/drm/tegra/hdmi.c b/drivers/gpu/drm/tegra/hdmi.c
index d09a24931..e5d2a4026 100644
--- a/drivers/gpu/drm/tegra/hdmi.c
+++ b/drivers/gpu/drm/tegra/hdmi.c
@@ -1510,7 +1510,7 @@ static int tegra_hdmi_runtime_resume(struct host1x_client *client)
 	struct device *dev = client->dev;
 	int err;
 
-	err = pm_runtime_get_sync(dev);
+	err = pm_runtime_resume_and_get(dev);
 	if (err < 0) {
 		dev_err(dev, "failed to get runtime PM: %d\n", err);
 		return err;
diff --git a/drivers/gpu/drm/tegra/hub.c b/drivers/gpu/drm/tegra/hub.c
index 22a03f7ff..5ce771cba 100644
--- a/drivers/gpu/drm/tegra/hub.c
+++ b/drivers/gpu/drm/tegra/hub.c
@@ -789,7 +789,7 @@ static int tegra_display_hub_runtime_resume(struct host1x_client *client)
 	unsigned int i;
 	int err;
 
-	err = pm_runtime_get_sync(dev);
+	err = pm_runtime_resume_and_get(dev);
 	if (err < 0) {
 		dev_err(dev, "failed to get runtime PM: %d\n", err);
 		return err;
diff --git a/drivers/gpu/drm/tegra/sor.c b/drivers/gpu/drm/tegra/sor.c
index e88a17c29..fa1272155 100644
--- a/drivers/gpu/drm/tegra/sor.c
+++ b/drivers/gpu/drm/tegra/sor.c
@@ -3214,7 +3214,7 @@ static int tegra_sor_runtime_resume(struct host1x_client *client)
 	struct device *dev = client->dev;
 	int err;
 
-	err = pm_runtime_get_sync(dev);
+	err = pm_runtime_resume_and_get(dev);
 	if (err < 0) {
 		dev_err(dev, "failed to get runtime PM: %d\n", err);
 		return err;
diff --git a/drivers/gpu/drm/tegra/vic.c b/drivers/gpu/drm/tegra/vic.c
index ade56b860..b77f72630 100644
--- a/drivers/gpu/drm/tegra/vic.c
+++ b/drivers/gpu/drm/tegra/vic.c
@@ -314,7 +314,7 @@ static int vic_open_channel(struct tegra_drm_client *client,
 	struct vic *vic = to_vic(client);
 	int err;
 
-	err = pm_runtime_get_sync(vic->dev);
+	err = pm_runtime_resume_and_get(vic->dev);
 	if (err < 0)
 		return err;
 
-- 
2.23.0

Re: [PATCH] drm/tegra: fix reference leak when pm_runtime_get_sync fails

[Thierry Reding]

[-- Attachment #1: Type: text/plain, Size: 916 bytes --]

On Tue, Dec 01, 2020 at 08:56:31PM +0800, Qinglang Miao wrote:
> The PM reference count is not expected to be incremented on
> return in these tegra functions.
> 
> However, pm_runtime_get_sync will increment the PM reference
> count even failed. Forgetting to putting operation will result
> in a reference leak here.
> 
> Replace it with pm_runtime_resume_and_get to keep usage
> counter balanced.
> 
> Fixes: fd67e9c6ed5a ("drm/tegra: Do not implement runtime PM")
> Reported-by: Hulk Robot <hulkci@huawei.com>
> Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
> ---
>  drivers/gpu/drm/tegra/dc.c   | 2 +-
>  drivers/gpu/drm/tegra/dsi.c  | 2 +-
>  drivers/gpu/drm/tegra/hdmi.c | 2 +-
>  drivers/gpu/drm/tegra/hub.c  | 2 +-
>  drivers/gpu/drm/tegra/sor.c  | 2 +-
>  drivers/gpu/drm/tegra/vic.c  | 2 +-
>  6 files changed, 6 insertions(+), 6 deletions(-)

Applied, thanks.

Thierry

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]