I think you'll have to look at the assembly produced for workqueue.c and
work out why GCC is referencing an undefined label.  You can get the
assembly for that by doing:

make ARCH=arm ...etc... kernel/workqueue.s

and then you'll have a kernel/workqueue.s in your object tree.
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Or make that:

make ARCH=arm ...etc... kernel/workqueue.lst

to get intermixed C and assenbly

	Sam
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On Fri, 2 Nov 2007 21:10:23 +0100
arm-unknown-linux-gnu- kernel/workqueue.1strrent:)$ make ARCH=arm CROSS_COMPILE=a
make: *** No rule to make target `kernel/workqueue.1st'.  Stop.
arm-unknown-linux-gnu- kernel/workqueue.lstrrent:)$ make ARCH=arm CROSS_COMPILE=a
  CHK     include/linux/version.h
make[1]: `include/asm-arm/mach-types.h' is up to date.
  CHK     include/linux/utsrelease.h
  CALL    scripts/checksyscalls.sh
<stdin>:1097:2: warning: #warning syscall fadvise64 not implemented
<stdin>:1265:2: warning: #warning syscall migrate_pages not implemented
<stdin>:1321:2: warning: #warning syscall pselect6 not implemented
<stdin>:1325:2: warning: #warning syscall ppoll not implemented
<stdin>:1365:2: warning: #warning syscall epoll_pwait not implemented
  MKLST   kernel/workqueue.lst
No System.map
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Suggest you use a better console font that allows you to identify

You're not looking for a system.map file, but the workqueue.s or
workqueue.lst file to find out where this nonexistent label is
referenced.
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On Sat, 3 Nov 2007 00:04:14 +0000

Sorry, I misunderstod Sam's reply earlier. Tried to compile the .lst file :D
I've done some checks in the .config and seems like some setting in 'kernel hacking', caused this. Unfortunantly I changed too much at once to be sure what exactly in there caused it. 

Anyhow, thanks for helping out :)
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