Early drop to debugger with DEBUG_MEMGUARD

[Jeff Roberson]

On Tue, 13 Aug 2013, Jeff Roberson wrote:

> On Mon, 12 Aug 2013, David Wolfskill wrote:
>
>> On Tue, Aug 13, 2013 at 08:29:44AM +0300, Konstantin Belousov wrote:
>>> ...
>>> The r254025 indeed introduced the problem, and Davide pointed out you a
>>> workaround for the assertion triggering.
>> 
>> Right; I tried one of those -- I hope I got it right...
>> 
>>> Proper fix for the memguard requires a policy of M_NEXTFIT or like, to
>>> avoid a reuse of the previous allocated range as long as possible.
>
> That's why I passed a start address as a lower bound to vmem_xalloc.  I would 
> like to eventually implement nextfit.
>
>> 
>> Ah.
>> 
>>> But, you have some further issue even after the assertion was silenced,
>>> isn't it ?
>
> I will fix this today and do some stress tests with memguard on.  Sorry for 
> the difficulty.

Please try 254308.  It is working for me.

Thanks,
Jeff

>
> Thanks,
> Jeff
>
>> 
>> Yes; please see
>> <http://docs.FreeBSD.org/cgi/mid.cgi?20130812160154.GF1570> for a copy
>> of the message that shows the resulting panic.  (Or see previous
>> messages i this thread, if that's easier.)  It looks (from my naive
>> perspective) as if mti_zone hadn't been initialized (properly?  at
>> all?).
>> 
>> In any case, I remain willing to test, subject to Internet connectivity
>> flakiness where I am now and other demands on my time.
>> 
>> Peace,
>> david
>> -- 
>> David H. Wolfskill				david at catwhisker.org
>> Taliban: Evil men with guns afraid of truth from a 14-year old girl.
>> 
>> See http://www.catwhisker.org/~david/publickey.gpg for my public key.
>> 
>