Re: [PATCH] sysrq, kdump: fix regression, revert "simplify sysrq-c handler"

[Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>]

Neil Horman wrote:
> On Wed, Jul 22, 2009 at 11:01:29AM +0900, Hidetoshi Seto wrote:
>> Neil Horman wrote:
>>  static void sysrq_handle_crash(int key, struct tty_struct *tty)
>>  {
>> -	char *killer = NULL;
>> -	*killer = 1;
>> +	panic("SysRq-triggered panic!\n");
>>  }
>>
> Well, this removes the ability from sysrq-c to test the oops handling path, but
> I suppose it does buy us consistent behavior between the keyboard and proc
> interfaces, which is likely more important.  I can agree to that.  Perhaps we
> can create another sysctl to test the oops path later.
> 
>> I agree that causing a real crash(panic) is better way to test crashdump than
>> calling the entry function of the crashdump directly, and also that opening
>> the path for other dump mechanisms is welcomed.
>>  
> Ok, so we're in line there :)
> 
>>> It seems to
>>> me that right now your major complaint is that the documentation is out of date,
>>> and you're having to do things slightly differently to get the same behavioral
>>> results.  Would it solve your issue, if we simply updated the documentation to
>>> illustrate how it works now?
>> Of course the documentation should be updated asap.
>> But I think the major complaint is about a difference in the behaviors of SysRq-c
>> and "echo c > /proc/sysrq-trigger".
>>
> Ok, I can agree with that.  I'd support a change like what you have above to
> bring the keyboard and proc interface behavior in line.

Thank you for your understanding!

I'll write & post a patch soon.  Please review it.


Thanks,
H.Seto