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Date: Sat, 19 Jun 2010 16:39:20 +0200
From: Ulrich =?utf-8?B?U3DDtnJsZWlu?= <uqs@spoerlein.net>
To: Andriy Gapon <avg@freebsd.org>
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Cc: freebsd-arch@freebsd.org
Subject: Re: KDB_TRACE in GENERIC
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On Sat, 19.06.2010 at 10:49:26 +0300, Andriy Gapon wrote:
> 
> I propose to add the following options into GENERIC (perhaps only i386 and amd64):
> 
> options         KDB
> options         KDB_TRACE
> options         KDB_UNATTENDED
> options		SC_DISABLE_KDBKEY  # <- not sure about his one
> 
> This would increase kernel size only by a fraction, would not result in any POLA
> violations (KDB_UNATTENDED, SC_DISABLE_KDBKEY) and would provide a useful service.
> 
> Currently we get many panic reports that are almost impossible to analyze
> because there is no stack trace.  Especially this is true for panics at
> installation time, when people use GENERIC from release media and do not have
> ability to try a custom kernel.
> 
> What do you think?

I'd rather propose we turn on textdumps, as many people will be in X11
when disaster strikes and there's no easy way to get the crashdump then.

But we would also need to bump the ddb capture buffer size
significantly, as it cannot hold information for more than a few dozen
processes right now.

Uli