Re: [PATCH 02/11] drm/panthor: Keep the reset work disabled until everything is initialized

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

On Thu, Jun 25, 2026 at 02:40:28PM +0200, Boris Brezillon wrote:
> The reset work will sub-component reset helpers, which might not be
> ready if the reset happens during initialization, leading to NULL
> pointer dereferences or worse.
> 
> Avoid that by keeping the reset work disabled while we're initializing
> those sub-components.
> 
> Fixes: 5fe909cae118 ("drm/panthor: Add the device logical block")
> Reported-by: sashiko-bot@kernel.org
> Closes: https://sashiko.dev/#/patchset/20260625-panthor-signal-from-irq-v5-0-8836a74e0ef9@collabora.com?part=4
> Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>

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

Best regards,
Liviu

> ---
>  drivers/gpu/drm/panthor/panthor_device.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/gpu/drm/panthor/panthor_device.c b/drivers/gpu/drm/panthor/panthor_device.c
> index bd417d6ae8c0..0b25abebb803 100644
> --- a/drivers/gpu/drm/panthor/panthor_device.c
> +++ b/drivers/gpu/drm/panthor/panthor_device.c
> @@ -207,6 +207,7 @@ int panthor_device_init(struct panthor_device *ptdev)
>  	*dummy_page_virt = 1;
>  
>  	INIT_WORK(&ptdev->reset.work, panthor_device_reset_work);
> +	disable_work(&ptdev->reset.work);
>  	ptdev->reset.wq = alloc_ordered_workqueue("panthor-reset-wq", 0);
>  	if (!ptdev->reset.wq)
>  		return -ENOMEM;
> @@ -285,6 +286,9 @@ int panthor_device_init(struct panthor_device *ptdev)
>  
>  	panthor_gem_init(ptdev);
>  
> +	/* Now that everything is initialized, we can enable the reset work. */
> +	enable_work(&ptdev->reset.work);
> +
>  	/* ~3 frames */
>  	pm_runtime_set_autosuspend_delay(ptdev->base.dev, 50);
>  	pm_runtime_use_autosuspend(ptdev->base.dev);
> 
> -- 
> 2.54.0
> 

-- 
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