[PATCH] drm/v3d: fix reference leak when pm_runtime_get_sync fails

From: Qinglang Miao
Date: Tue Dec 01 2020 - 07:49:43 EST


The PM reference count is not expected to be incremented on
return in functions v3d_get_param_ioctl and v3d_job_init.

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: 57692c94dcbe ("drm/v3d: Introduce a new DRM driver for Broadcom V3D V3.x+")
Fixes: 935f3d88434b ("drm/v3d: Make sure the GPU is on when measuring clocks.")
Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Qinglang Miao <miaoqinglang@xxxxxxxxxx>
---
drivers/gpu/drm/v3d/v3d_debugfs.c | 4 ++--
drivers/gpu/drm/v3d/v3d_gem.c | 2 +-
2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/v3d/v3d_debugfs.c b/drivers/gpu/drm/v3d/v3d_debugfs.c
index e76b24bb8..91ceed774 100644
--- a/drivers/gpu/drm/v3d/v3d_debugfs.c
+++ b/drivers/gpu/drm/v3d/v3d_debugfs.c
@@ -132,7 +132,7 @@ static int v3d_v3d_debugfs_ident(struct seq_file *m, void *unused)
u32 ident0, ident1, ident2, ident3, cores;
int ret, core;

- ret = pm_runtime_get_sync(v3d->drm.dev);
+ ret = pm_runtime_resume_and_get(v3d->drm.dev);
if (ret < 0)
return ret;

@@ -219,7 +219,7 @@ static int v3d_measure_clock(struct seq_file *m, void *unused)
int measure_ms = 1000;
int ret;

- ret = pm_runtime_get_sync(v3d->drm.dev);
+ ret = pm_runtime_resume_and_get(v3d->drm.dev);
if (ret < 0)
return ret;

diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c
index 182c58652..765683569 100644
--- a/drivers/gpu/drm/v3d/v3d_gem.c
+++ b/drivers/gpu/drm/v3d/v3d_gem.c
@@ -439,7 +439,7 @@ v3d_job_init(struct v3d_dev *v3d, struct drm_file *file_priv,
job->v3d = v3d;
job->free = free;

- ret = pm_runtime_get_sync(v3d->drm.dev);
+ ret = pm_runtime_resume_and_get(v3d->drm.dev);
if (ret < 0)
return ret;

--
2.23.0