6.1-RELEASE / 6.2 Kernel Crash...
jan at digitaldaemon.com
Fri Dec 29 14:33:07 PST 2006
Robert Watson wrote:
> On Thu, 28 Dec 2006, Jan Knepper wrote:
>>> Sounds like a bug in the support for your ATA hardware, or your
>>> hardware is broken. The very least you'll need to do is to obtain a
>>> crashdump and debugging backtrace (see the developers handbook) and
>>> CC it to sos@
>> This is getting funnier...
>> I added:
>> to: rc.conf
>> Rebooted the system and tried to get it to crash again...
>> And indeed it does in process 9: taskq
>> Then it starts dumping which takes a couple of seconds as the machine
>> has 2 GB Ram...
>> Than it reboots... and the next thing you know... savecore does NOT
>> recognize a dump on the swap file system. If does not save anything
>> to /var/crash... <sigh> Tried this about 10 times... No luck...
>> Any other idea's?
> Yeah, unfortunately if some combination of storage driver and hardware
> aren't working, it's hard to get a dump...
> The usual fallback here is to use a serial console to capture
> debugging information from DDB and to skip the dump side of things.
> In fact, I prefer debugging that way most of the time. The reason for
> using a serial console (or firewire) is to avoid having to hand-copy
> trap and debugging information, which gets very painful very quickly.
> Compile DDB and KDB into your kernel, and configure a serial console,
> and a panic should lead to the system entering the debugger. The
> usual first command to type is "trace" to generate a backtrace; it's
> often useful also to do "show pcpu", "show allpcpu", "alltrace", and
> "ps", although for the problem you're seeing the last two may be less
> The 0x50 trap address in your post suggests this is a NULL pointer
> dereference. What we now need to do is work out what piece of code is
> dereferencing the pointer improperly, which is where the backtrace
> comes in.
> If you could copy and paste all that DDB/KDB output into an e-mail
> (or, perhaps more ideally, a PR), that would be great.
Thanks for the reply Robert.
Since this machine runs at my house I hope to get to this over the
weekend. I will definitely try to get this information out as soon as I
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