Subject: [PATCH v2 04/13] uprobes: allow arch-specific initialization

From: [email-masked] (Oleg Nesterov)
Date: Sat, 19 Oct 2013 18:42:23 +0200

On 10/15, David Long wrote:
>
> Add a weak function for any architecture-specific initialization.  ARM
> will use this to register the handlers for the undefined instructions it
> uses to implement uprobes.

Could you explain why ARM can't simply do the necessary initialization in
arch/arm/kernel/uprobes-arm.c ?

> +int __weak __init arch_uprobes_init(void)
> +{
> +	return 0;
> +}
> +
>  static int __init init_uprobes(void)
>  {
> +	int ret;
>  	int i;
>  
>  	for (i = 0; i < UPROBES_HASH_SZ; i++)
> @@ -1870,6 +1876,10 @@ static int __init init_uprobes(void)
>  	if (percpu_init_rwsem(&dup_mmap_sem))
>  		return -ENOMEM;
>  
> +	ret = arch_uprobes_init();
> +	if (ret)
> +		return ret;
> +
>  	return register_die_notifier(&uprobe_exception_nb);
>  }
>  module_init(init_uprobes);

IOW, why do we need to call arch_uprobes_init() from init_uprobes().

Oleg.