Re: [PATCH] avr32: init cannot ignore signals sent by force_sig_info()

[Oleg Nesterov <oleg@redhat.com>]

On 04/04, Matt Fleming wrote:
>
> --- a/arch/avr32/kernel/traps.c
> +++ b/arch/avr32/kernel/traps.c
> @@ -95,28 +95,6 @@ void _exception(long signr, struct pt_regs *regs, int code,
>  	info.si_code = code;
>  	info.si_addr = (void __user *)addr;
>  	force_sig_info(signr, &info, current);
> -
> -	/*
> -	 * Init gets no signals that it doesn't have a handler for.
> -	 * That's all very well, but if it has caused a synchronous
> -	 * exception and we ignore the resulting signal, it will just
> -	 * generate the same exception over and over again and we get
> -	 * nowhere.  Better to kill it and let the kernel panic.
> -	 */
> -	if (is_global_init(current)) {
> -		__sighandler_t handler;
> -
> -		spin_lock_irq(&current->sighand->siglock);
> -		handler = current->sighand->action[signr-1].sa.sa_handler;
> -		spin_unlock_irq(&current->sighand->siglock);
> -		if (handler == SIG_DFL) {
> -			/* init has generated a synchronous exception
> -			   and it doesn't have a handler for the signal */
> -			printk(KERN_CRIT "init has generated signal %ld "
> -			       "but has no handler for it\n", signr);
> -			do_exit(signr);
> -		}
> -	}

Reviewed-by: Oleg Nesterov <oleg@redhat.com>