2020-11-27 09:45:47

by Qinglang Miao

Subject: [PATCH] drm/lima: fix reference leak in lima_pm_busy

pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to putting operation will result in a
reference leak here.

A new function pm_runtime_resume_and_get is introduced in
[0] to keep usage counter balanced. So We fix the reference
leak by replacing it with new funtion.

[0] dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")

Fixes: 50de2e9ebbc0 ("drm/lima: enable runtime pm")
Reported-by: Hulk Robot <[email protected]>
Signed-off-by: Qinglang Miao <[email protected]>
---
drivers/gpu/drm/lima/lima_sched.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/lima/lima_sched.c b/drivers/gpu/drm/lima/lima_sched.c
index dc6df9e9a..f6e7a88a5 100644
--- a/drivers/gpu/drm/lima/lima_sched.c
+++ b/drivers/gpu/drm/lima/lima_sched.c
@@ -200,7 +200,7 @@ static int lima_pm_busy(struct lima_device *ldev)
int ret;

/* resume GPU if it has been suspended by runtime PM */
- ret = pm_runtime_get_sync(ldev->dev);
+ ret = pm_runtime_resume_and_get(ldev->dev);
if (ret < 0)
return ret;

--
2.23.0

2021-01-30 09:26:10

by Qiang Yu

Subject: Re: [PATCH] drm/lima: fix reference leak in lima_pm_busy

Thanks, applied to drm-misc-next.

Regards,
Qiang

On Fri, Nov 27, 2020 at 5:42 PM Qinglang Miao <[email protected]> wrote:
>
> pm_runtime_get_sync will increment pm usage counter even it
> failed. Forgetting to putting operation will result in a
> reference leak here.
>
> A new function pm_runtime_resume_and_get is introduced in
> [0] to keep usage counter balanced. So We fix the reference
> leak by replacing it with new funtion.
>
> [0] dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
>
> Fixes: 50de2e9ebbc0 ("drm/lima: enable runtime pm")
> Reported-by: Hulk Robot <[email protected]>
> Signed-off-by: Qinglang Miao <[email protected]>
> ---
> drivers/gpu/drm/lima/lima_sched.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/lima/lima_sched.c b/drivers/gpu/drm/lima/lima_sched.c
> index dc6df9e9a..f6e7a88a5 100644
> --- a/drivers/gpu/drm/lima/lima_sched.c
> +++ b/drivers/gpu/drm/lima/lima_sched.c
> @@ -200,7 +200,7 @@ static int lima_pm_busy(struct lima_device *ldev)
> int ret;
>
> /* resume GPU if it has been suspended by runtime PM */
> - ret = pm_runtime_get_sync(ldev->dev);
> + ret = pm_runtime_resume_and_get(ldev->dev);
> if (ret < 0)
> return ret;
>
> --
> 2.23.0
>