Re: [PATCH] genirq: Fix uninitialized request_mutex

[Mukesh Ojha]

On 4/4/2019 1:15 PM, Kefeng Wang wrote:
> When !CONFIG_SPARSE_IRQ, request_mutex of struct irq_desc won't
> be initialiezed, it leads to system hung, fix it.
>
> Fixes: 9114014cf4e6 ("genirq: Add mutex to irq desc to serialize request/free_irq()")
> Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>


Reviewed-by: Mukesh Ojha <mojha@xxxxxxxxxxxxxx>

Cheers,
-Mukesh

> ---
>   kernel/irq/irqdesc.c | 1 +
>   1 file changed, 1 insertion(+)
>
> diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
> index 13539e12cd80..9f8a709337cf 100644
> --- a/kernel/irq/irqdesc.c
> +++ b/kernel/irq/irqdesc.c
> @@ -558,6 +558,7 @@ int __init early_irq_init(void)
>   		alloc_masks(&desc[i], node);
>   		raw_spin_lock_init(&desc[i].lock);
>   		lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
> +		mutex_init(&desc[i].request_mutex);
>   		desc_set_defaults(i, &desc[i], node, NULL, NULL);
>   	}
>   	return arch_early_irq_init();