Re: [PATCH v3 3/7] drm/panthor: Replace the panthor_irq macro machinery by inline helpers

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [High] Hardware interrupts are unmasked before the OS interrupt handler is successfully registered, risking an unhandled IRQ storm.
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commit 4e867b9890a5ecc61feefa09f80bbc3aaddcd675
Author: Boris Brezillon <boris.brezillon@collabora.com>

drm/panthor: Replace the panthor_irq macro machinery by inline helpers

This commit removes the panthor_irq macro generation logic and replaces it
with inline helpers to rely on compiler optimization. It also refactors the
prototype of IRQ handlers to take struct panthor_irq instead of struct
panthor_device.

> diff --git a/drivers/gpu/drm/panthor/panthor_device.h b/drivers/gpu/drm/panthor/panthor_device.h
> --- a/drivers/gpu/drm/panthor/panthor_device.h
> +++ b/drivers/gpu/drm/panthor/panthor_device.h
[ ... ]
> +static inline int
> +panthor_irq_request(struct panthor_device *ptdev, struct panthor_irq *pirq,
> +		    int irq, u32 mask, void __iomem *iomem, const char *name,
> +		    irqreturn_t (*threaded_handler)(int, void *data))
> +{
[ ... ]
> +	panthor_irq_resume(pirq);
> +	return devm_request_threaded_irq(ptdev->base.dev, irq,
> +					 panthor_irq_default_raw_handler,
> +					 threaded_handler,
> +					 IRQF_SHARED, full_name, pirq);
>  }

[Severity: High]
This is a pre-existing issue, but by calling panthor_irq_resume() before
devm_request_threaded_irq(), does this leave a window where the hardware
interrupt is unmasked before the OS handler is successfully registered?

If the device asserts an interrupt before the handler is fully registered,
or if devm_request_threaded_irq() fails entirely and returns without
subsequently masking the hardware interrupt, could this unhandled interrupt
trigger an IRQ storm? This might cause the kernel's irq core to permanently
disable the shared interrupt line.

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Sashiko AI review · https://sashiko.dev/#/patchset/20260623-panthor-signal-from-irq-v3-0-2ece396f8ee0@collabora.com?part=3