Re: [PATCH] drm/panthor: Check debugfs GEM lock initialization

[Liviu Dudau <liviu.dudau@arm.com>]

On Mon, Jul 13, 2026 at 04:29:12PM +0800, Linmao Li wrote:
> drmm_mutex_init() can fail while registering the managed cleanup action.
> When that happens, drmm_add_action_or_reset() destroys the mutex before
> returning the error. Continuing initialization would therefore leave the
> debugfs GEM object list with an unusable lock.
> 
> Propagate the error as is already done for the other managed mutexes in
> panthor_device_init().
> 
> Fixes: a3707f53eb3f ("drm/panthor: show device-wide list of DRM GEM objects over DebugFS")
> Signed-off-by: Linmao Li <lilinmao@kylinos.cn>

Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>

Best regards,
Liviu

> ---
>  drivers/gpu/drm/panthor/panthor_device.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/panthor/panthor_device.c b/drivers/gpu/drm/panthor/panthor_device.c
> index 0b25abebb803..9687c59de350 100644
> --- a/drivers/gpu/drm/panthor/panthor_device.c
> +++ b/drivers/gpu/drm/panthor/panthor_device.c
> @@ -182,7 +182,10 @@ int panthor_device_init(struct panthor_device *ptdev)
>  		return ret;
>  
>  #ifdef CONFIG_DEBUG_FS
> -	drmm_mutex_init(&ptdev->base, &ptdev->gems.lock);
> +	ret = drmm_mutex_init(&ptdev->base, &ptdev->gems.lock);
> +	if (ret)
> +		return ret;
> +
>  	INIT_LIST_HEAD(&ptdev->gems.node);
>  #endif
>  
> -- 
> 2.25.1
> 

-- 
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