kern/68442: panic - acquiring duplicate lock of same type: "sleepq chain"

Daniel Lang dl at
Tue Jun 29 11:35:59 PDT 2004

Hi Brian,

Brian Fundakowski Feldman wrote on Tue, Jun 29, 2004 at 01:00:14PM -0400:
> You can find it out without using gdb, too.  This will work for
> only main kernel symbols, but you can do something similar for
> KLDs.  Say I want to find a symbol that's in the main kernel object:
> $ objdump -t /boot/kernel/kernel | ruby -ne 'fields = $_.split; if fields[3] == ".text" and fields[2] == "F" and 0xc048a800.between?(fields[0].hex, fields[0].hex + fields[4].hex) then puts $_ end'
> c048a7ac l     F .text  0000006b cbb_removal

Thanks for that hint, but Colin suggested to use "addr2line", which
produced some result. Maybe addr2line does a similar thing
as your objdump/ruby script:

So I have a line of code for the failing address:

# addr2line -e kernel.debug 0xc053932b

which is (in my kernel):

        lock1 = &(*lock_list)->ll_children[(*lock_list)->ll_count - 1];

Well, I'm not sure if this is a big help. I doubt there is a bug
in witness code.

I'll cross-check with gdb to see if there is the same
result. Too bad I couldn't get a crashdump. 

(What hurts most, is, that in one occasion I had a ddb prompt
and could call doadump() successfully. But after reboot, damn 
/var was full, so savecore could not write it to disk, argl!).

Best regards,
IRCnet: Mr-Spock                  - Soon I will be free, then hungry. -  
 Daniel Lang * dl at * +49 89 289 18532 *

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