can not resolve global kernel variable.

[Kyle McMartin]

On Tue, Feb 19, 2008 at 06:43:16PM +0200, Eugene Goubine wrote:
> Kyle, thanks for reffering,but it seems like GPL is not the case.
> I want to write a module to track netdevices present.
> Sort of a protocol sitting there. It is GPL'ed, but register_pm_notifier
> usage ( as you can see in sources)
> gives linker warning "pm_chain_head undefined",since register_pm_notifier is
> "static inline" and expanded
> to blocking_notifier_chain_unregister(&pm_chain_head, nb).
> Why do you say pm_chain_head is static there ? Is it because it is not
> exported by EXPORT_SYMBOL ?

What kernel are you building against? Do you have CONFIG_PM_SLEEP=y?

cheers, Kyle


> So what does it have to do with the license ( which is already GPL, but I
> just do not understand ).

nothing in particular, it's just a linking restriction that might have
bitten you if you didn't know while writing your own module. (that there
are two different kinds of export, i mean.)