Subject: Re: randconfig build error with next-20150302, in drivers/net/ethernet/intel/i40e/i40e_configfs.c

From: Jeff Kirsher <[email-masked]>
Date: Mon, 02 Mar 2015 15:03:54 -0800

On Mon, 2015-03-02 at 09:29 -0700, Jim Davis wrote:
> Building with the attached random configuration file,
> 
> drivers/built-in.o: In function `i40e_cfgfs_group_make_item':
> i40e_configfs.c:(.text+0x3df4ce): undefined reference to
> `config_item_init_type_name'
> drivers/built-in.o: In function `i40e_configfs_init':
> (.text+0x3df4ee): undefined reference to `config_group_init'
> drivers/built-in.o: In function `i40e_configfs_init':
> (.text+0x3df50c): undefined reference to `configfs_register_subsystem'
> drivers/built-in.o: In function `i40e_configfs_exit':
> (.text+0x3df52e): undefined reference to `configfs_unregister_subsystem'
> Makefile:939: recipe for target 'vmlinux' failed

We found this issue and already have a patch to resolve the problem.
The issue is that we cannot have configfs as a module when our driver is
compiled into the kernel.  The solution is to use the similar Kconfig
logic we used for PTP (which had the same issue) for configfs.

I should have the patch pushed upstream in the next batch of patches I
push upstream.