[PATCH] drm/lima: fix autosuspend cleanup during teardown

Guangshuo Li posted 1 patch 1 month, 3 weeks ago
drivers/gpu/drm/lima/lima_drv.c | 2 ++
1 file changed, 2 insertions(+)
[PATCH] drm/lima: fix autosuspend cleanup during teardown
Posted by Guangshuo Li 1 month, 3 weeks ago
lima_pdev_probe() calls pm_runtime_use_autosuspend(), but its failure
path does not call the matching pm_runtime_dont_use_autosuspend()
before disabling runtime PM. The remove path has the same issue.

In particular, lima_pdev_remove() explicitly sets the autosuspend
delay to -1 while autosuspend is still enabled. A negative autosuspend
delay can increase usage_count to prevent runtime suspend. Without
calling pm_runtime_dont_use_autosuspend(), this reference is not
dropped before runtime PM is disabled, leaving usage_count unbalanced.

The documentation for pm_runtime_use_autosuspend() also notes that it
is important to undo it with pm_runtime_dont_use_autosuspend() at
driver exit time, unless runtime PM was initially enabled with
devm_pm_runtime_enable().

Add the missing pm_runtime_dont_use_autosuspend() calls to the probe
failure and remove paths.

This issue was found by manual code inspection.

Fixes: 50de2e9ebbc0 ("drm/lima: enable runtime pm")
Cc: stable@vger.kernel.org
Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
---
 drivers/gpu/drm/lima/lima_drv.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/lima/lima_drv.c b/drivers/gpu/drm/lima/lima_drv.c
index 9a0eb1092ad3..9bd44c191e6c 100644
--- a/drivers/gpu/drm/lima/lima_drv.c
+++ b/drivers/gpu/drm/lima/lima_drv.c
@@ -434,6 +434,7 @@ static int lima_pdev_probe(struct platform_device *pdev)
 	return 0;
 
 err_out3:
+	pm_runtime_dont_use_autosuspend(ldev->dev);
 	pm_runtime_disable(ldev->dev);
 	lima_devfreq_fini(ldev);
 err_out2:
@@ -456,6 +457,7 @@ static void lima_pdev_remove(struct platform_device *pdev)
 
 	/* stop autosuspend to make sure device is in active state */
 	pm_runtime_set_autosuspend_delay(ldev->dev, -1);
+	pm_runtime_dont_use_autosuspend(ldev->dev);
 	pm_runtime_disable(ldev->dev);
 
 	lima_devfreq_fini(ldev);
-- 
2.43.0
Re: [PATCH] drm/lima: fix autosuspend cleanup during teardown
Posted by Krzysztof Kozlowski 1 month, 1 week ago
On 08/08/2026 14:59, Guangshuo Li wrote:
> lima_pdev_probe() calls pm_runtime_use_autosuspend(), but its failure
> path does not call the matching pm_runtime_dont_use_autosuspend()
> before disabling runtime PM. The remove path has the same issue.
> 
> In particular, lima_pdev_remove() explicitly sets the autosuspend
> delay to -1 while autosuspend is still enabled. A negative autosuspend
> delay can increase usage_count to prevent runtime suspend. Without
> calling pm_runtime_dont_use_autosuspend(), this reference is not
> dropped before runtime PM is disabled, leaving usage_count unbalanced.
> 
> The documentation for pm_runtime_use_autosuspend() also notes that it
> is important to undo it with pm_runtime_dont_use_autosuspend() at
> driver exit time, unless runtime PM was initially enabled with
> devm_pm_runtime_enable().
> 
> Add the missing pm_runtime_dont_use_autosuspend() calls to the probe
> failure and remove paths.
> 
> This issue was found by manual code inspection.
> 
> Fixes: 50de2e9ebbc0 ("drm/lima: enable runtime pm")
> Cc: stable@vger.kernel.org
> Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
> ---

You sent vast amount of patches, all separate, making it very difficult
to track and respond in efficient way. Do not do that.

Group your work per subsystem.

You were asked to clarify and respond to incorrect fixes statement. I do
not see how you clarified and responded at all.

Best regards,
Krzysztof
Re: [PATCH] drm/lima: fix autosuspend cleanup during teardown
Posted by Guangshuo Li 1 month ago
Hi Krzysztof,

On Thu, 20 Aug 2026 at 22:50, Krzysztof Kozlowski <krzk@kernel.org> wrote:
>
> On 08/08/2026 14:59, Guangshuo Li wrote:
> > lima_pdev_probe() calls pm_runtime_use_autosuspend(), but its failure
> > path does not call the matching pm_runtime_dont_use_autosuspend()
> > before disabling runtime PM. The remove path has the same issue.
> >
> > In particular, lima_pdev_remove() explicitly sets the autosuspend
> > delay to -1 while autosuspend is still enabled. A negative autosuspend
> > delay can increase usage_count to prevent runtime suspend. Without
> > calling pm_runtime_dont_use_autosuspend(), this reference is not
> > dropped before runtime PM is disabled, leaving usage_count unbalanced.
> >
> > The documentation for pm_runtime_use_autosuspend() also notes that it
> > is important to undo it with pm_runtime_dont_use_autosuspend() at
> > driver exit time, unless runtime PM was initially enabled with
> > devm_pm_runtime_enable().
> >
> > Add the missing pm_runtime_dont_use_autosuspend() calls to the probe
> > failure and remove paths.
> >
> > This issue was found by manual code inspection.
> >
> > Fixes: 50de2e9ebbc0 ("drm/lima: enable runtime pm")
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
> > ---
>
> You sent vast amount of patches, all separate, making it very difficult
> to track and respond in efficient way. Do not do that.
>
> Group your work per subsystem.
>
> You were asked to clarify and respond to incorrect fixes statement. I do
> not see how you clarified and responded at all.
>
> Best regards,
> Krzysztof

Sorry about that. I should have replied to the earlier review comments
explicitly, and I also should not have sent so many separate patches.

I will group future patches by subsystem and make sure to respond
clearly to review feedback before resending.

Thanks for pointing this out.

Best regards,
Guangshuo