Re: Unresolved symbol error in __wake_up_sync

[Roland Dreier]

    sudharsan> We wrote a module in which we used
    sudharsan> wake_up_interruptible, wake_up_interruptible_sync calls
    sudharsan> and when I compiled it into a module with the
    sudharsan> appropriate Macros, it gets compiled properly.  But
    sudharsan> once, when I try to load the module with insmod, I get
    sudharsan> __wake_up_sync - unresolved symbol?  What module should
    sudharsan> I load to get out this error?

You don't need to load another module, since __wake_up_sync is part of
the kernel.  You are probably running into a problem with module
versions.  When you do:

    $ grep __wake_up_sync /proc/ksyms 

you will probably get something like:

    c01147e0 __wake_up_sync_R08c2a6b5

The _R08c2a6b5 part of the symbol name is the version, which comes
from the ".ver" files in your kernel include tree.  You will have to
include <linux/modversions.h> to get the correct definition for
__wake_up_sync.

By the way, 2.4.7 is an extremely old kernel, and you may avoid
problems by moving to something newer.

Best,
  Roland