Re: [RFC PATCH] kernel/signal.c: avoid BUG_ON with SIG128 (MIPS)

[Oleg Nesterov <oleg@redhat.com>]

On 05/29, David Daney wrote:
>
> On 05/29/2013 10:01 AM, James Hogan wrote:
>> MIPS has 128 signals, the highest of which has the number 128. The
>
> I wonder if we should change the ABI and reduce the number of signals to
> 127 instead of this patch.

Same thoughts...

>> @@ -2366,8 +2366,12 @@ relock:
>>
>>   		/*
>>   		 * Death signals, no core dump.
>> +		 *
>> +		 * MIPS has a signal number 128 which clashes with the core dump
>> +		 * bit. If this was the signal we still want to report a valid
>> +		 * exit code, so round it down to 127.
>>   		 */
>> -		do_group_exit(info->si_signo);
>> +		do_group_exit(min(info->si_signo, 127));

This avoids BUG_ON() but obviously fools WIFSIGNALED(), doesn't look
very nice.

Oleg.