Re: [PATCH 1/4] genirq/irq_sim: dispose of remaining mappings before removing the domain

[Andy Shevchenko]

On Sat, Aug 12, 2023 at 09:44:54PM +0200, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
> 
> If the device providing simulated interrupts is unbound (real life
> example: gpio-sim is disabled with users that didn't free their irqs)
> and removes the simulated domain while interrupts are still requested,
> we will hit memory issues when they are eventually freed and the
> mappings destroyed in the process.
> 
> Specifically we'll access freed memory in __irq_domain_deactivate_irq().
> 
> Dispose of all mappings before removing the simulator domain.

...

> +#include <linux/list.h>

Maybe ordered?

>  #include <linux/irq.h>
>  #include <linux/irq_sim.h>
>  #include <linux/irq_work.h>

...

> @@ -16,12 +17,14 @@ struct irq_sim_work_ctx {
>  	unsigned int		irq_count;
>  	unsigned long		*pending;
>  	struct irq_domain	*domain;
> +	struct list_head	irqs;
>  };
>  
>  struct irq_sim_irq_ctx {
>  	int			irqnum;
>  	bool			enabled;
>  	struct irq_sim_work_ctx	*work_ctx;

> +	struct list_head	siblings;

You can reduce the code size by moving this to be the first member.
Not sure about struct irq_sim_work_ctx, you can play with bloat-o-meter.

>  };

-- 
With Best Regards,
Andy Shevchenko