R: Re: 6.4-RC2 crashes after a few minutes of uptime

Rory Arms rorya+freebsd.org at TrueStep.com
Sun Nov 23 20:53:03 PST 2008


On 2008-11-23, at 18:36 , Barbara wrote:

>>> About kgdb...
>>> I never used freebsd-update, so sorry if I'm saying
> something
>>> stupid, but could it be the case that the kernel has been
> built
>>> without debugging symbols or something like that? Does freebsd-
>>>
> update provide a kernel.debug?
>>
>> I haven't had to use a the kernel.debug file
> in the obj dir in a long
>> time. As far as I know, these days, the GENERIC
> kernel includes debug
>> symbols. And in cases when there aren't any debug
> symbols, that
>> shouldn't prevent kgdb from loading, I wouldn't think.
>
> Hello,
>
> I had a k panic some hours ago but I think that's related to a  
> problem with one
> of my HDs.
>
> I've got a dump in /var/crash, and as you were interested, I run:
>
>
>    # kgdb /boot/kernel/kernel /var/crash/vmcore.6
>
>
>    GNU gdb 6.1.1
> [FreeBSD]
>
>    Copyright 2004 Free Software Foundation, Inc.
>
>    GDB is free
> software, covered by the GNU General Public License, and you are
>
>    welcome
> to change it and/or distribute copies of it under certain conditions.
>
>    Type
> "show copying" to see the conditions.
>
>    There is absolutely no warranty for
> GDB.  Type "show warranty" for details.
>
>    This GDB was configured as "i386-
> marcel-freebsd"...(no debugging symbols found)...
>
>    Attempt to extract a
> component of a value that is not a structure pointer.
>
>    Attempt to extract a
> component of a value that is not a structure pointer.
>
>    Attempt to extract a
> component of a value that is not a structure pointer.
>
>    Attempt to extract a
> component of a value that is not a structure pointer.
>
>    Terminated
>
>
> I had
> to pkill kgdb as it was in a loop.
>
> Running it against kernel.debug in
> /usr/obj/usr/src/sys/$KERNCONF/ worked as expected.
> I've always followed this
> way, so I don't know if it was working with earlier releases.

Ah, well you must not be using GENERIC then, because it does have the  
debugging symbols.

I think this is the setting in the GENERIC config that controls it:

makeoptions	DEBUG=-g

But I guess what you're doing works if you're using a custom kernel  
that does not have that config setting.

- rory


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