Re: [PATCH] drm/nouveau: fix autosuspend cleanup during teardown

[lyude@redhat.com]

Reviewed-by: Lyude Paul <lyude@redhat.com>

Will push to drm-misc-fixes in just a moment

On Sat, 2026-08-08 at 21:41 +0800, Guangshuo Li wrote:
> nouveau_drm_device_init() calls pm_runtime_use_autosuspend(), but
> nouveau_drm_device_fini() does not call the matching
> pm_runtime_dont_use_autosuspend().
> 
> If the autosuspend delay is set to a negative value while autosuspend
> is enabled, the runtime PM core increments usage_count to prevent
> runtime suspend. Without calling pm_runtime_dont_use_autosuspend()
> during teardown, this reference is not dropped and usage_count
> remains
> 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() call to the common
> device teardown path.
> 
> This issue was found by manual code inspection.
> 
> Fixes: 5addcf0a5f0f ("nouveau: add runtime PM support (v0.9)")
> Cc: stable@vger.kernel.org
> Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
> ---
>  drivers/gpu/drm/nouveau/nouveau_drm.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c
> b/drivers/gpu/drm/nouveau/nouveau_drm.c
> index e16f59b00f6f..1579a4b0785e 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_drm.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_drm.c
> @@ -585,6 +585,7 @@ nouveau_drm_device_fini(struct nouveau_drm *drm)
>  	if (nouveau_pmops_runtime()) {
>  		pm_runtime_get_sync(dev->dev);
>  		pm_runtime_forbid(dev->dev);
> +		pm_runtime_dont_use_autosuspend(dev->dev);
>  	}
>  
>  	nouveau_led_fini(dev);