Re: [PATCH] netconsole: fix build when CONFIG_NETCONSOLE_DYNAMIC is turned on

[Ben Hutchings <bhutchings@solarflare.com>]

On Mon, 2011-06-20 at 21:25 -0700, Randy Dunlap wrote:
> From: Randy Dunlap <randy.dunlap@oracle.com>
> 
> When NETCONSOLE_DYNAMIC=y and CONFIGFS_FS=m, there are build errors
> in netconsole:
> 
> drivers/built-in.o: In function `drop_netconsole_target':
> netconsole.c:(.text+0x1a100f): undefined reference to `config_item_put'
> drivers/built-in.o: In function `make_netconsole_target':
> netconsole.c:(.text+0x1a10b9): undefined reference to `config_item_init_type_name'
> drivers/built-in.o: In function `write_msg':
> netconsole.c:(.text+0x1a11a4): undefined reference to `config_item_get'
> netconsole.c:(.text+0x1a1211): undefined reference to `config_item_put'
> drivers/built-in.o: In function `netconsole_netdev_event':
> netconsole.c:(.text+0x1a12cc): undefined reference to `config_item_put'
> netconsole.c:(.text+0x1a12ec): undefined reference to `config_item_get'
> netconsole.c:(.text+0x1a1366): undefined reference to `config_item_put'
> drivers/built-in.o: In function `init_netconsole':
> netconsole.c:(.init.text+0x953a): undefined reference to `config_group_init'
> netconsole.c:(.init.text+0x9560): undefined reference to `configfs_register_subsystem'
> drivers/built-in.o: In function `dynamic_netconsole_exit':
> netconsole.c:(.exit.text+0x809): undefined reference to `configfs_unregister_subsystem'
> 
> so make NETCONSOLE_DYNAMIC require CONFIGFS_FS=y to fix the build errors.
[...]

NETCONSOLE is tristate, and I think NETCONSOLE=m && NETCONSOLE_DYNAMIC=y
&& CONFIGFS_FS=m should be OK.

It seems like Kconfig should have a '>=' operator which behaves like a
numeric comparison with n=0, m=1, y=2.  Then we could use a dependency
of:
	NETCONSOLE && SYSFS && CONFIGFS_FS>=NETCONSOLE

But for now I think the correct dependency is:
	NETCONSOLE && SYSFS && CONFIGFS_FS && !(NETCONSOLE=y && CONFIGFS_FS=m)

Ben.

-- 
Ben Hutchings, Senior Software Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.