Re: build breakage due to br_multicast.c referencing ipv6_dev_get_saddr()

["Jan Beulich" <JBeulich@novell.com>]

>>> On 16.03.11 at 18:49, David Miller <davem@davemloft.net> wrote:
> From: Stephen Hemminger <shemminger@linux-foundation.org>
> Date: Wed, 16 Mar 2011 08:24:41 -0700
> 
>> On Wed, 16 Mar 2011 12:34:19 +0000
>> "Jan Beulich" <JBeulich@novell.com> wrote:
>> 
>>> With BRIDGE=y and IPV6=m commit
>>> fe29ec41aaa51902aebd63658dfb04fe6fea8be5 ("bridge: Use IPv6
>>> link-local address for multicast listener queries") causes the build to
>>> break.
>> 
>> Rather than continue with the config games, lets just make the necessary
>> ipv6 pieces accessible.
> 
> You can't Stephen, ipv6_dev_get_saddr() requires access to the actual ipv6
> device state, that means you have to pull in the entire ipv6 stack in 
> because
> there are dependencies all the way down into the routing code.
> 
> We added a Kconfig fix to cure this specific problem, which made it
> into 2.6.38-final, so I don't understand why Jan is even seeing this,
> it's supposed to force BRIDGE modular if IPV6 is modular:

Oh, sorry, I was still on -rc7.

Nevertheless, I don't think this is the right way to fix it (nor
in infiniband and possibly ip_vs as pointed out).

Jan

> commit dcbcdf22f500ac6e4ec06485341024739b9dc241
> Author: Randy Dunlap <randy.dunlap@oracle.com>
> Date:   Thu Mar 10 13:45:57 2011 -0800
> 
>     net: bridge builtin vs. ipv6 modular
>     
>     When configs BRIDGE=y and IPV6=m, this build error occurs:
>     
>     br_multicast.c:(.text+0xa3341): undefined reference to 
> `ipv6_dev_get_saddr'
>     
>     BRIDGE_IGMP_SNOOPING is boolean; if it were tristate, then adding
>     	depends on IPV6 || IPV6=n
>     to BRIDGE_IGMP_SNOOPING would be a good fix.  As it is currently,
>     making BRIDGE depend on the IPV6 config works.
>     
>     Reported-by: Patrick Schaaf <netdev@bof.de>
>     Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
>     Signed-off-by: David S. Miller <davem@davemloft.net>
> 
> diff --git a/net/bridge/Kconfig b/net/bridge/Kconfig
> index 9190ae4..6dee7bf 100644
> --- a/net/bridge/Kconfig
> +++ b/net/bridge/Kconfig
> @@ -6,6 +6,7 @@ config BRIDGE
>  	tristate "802.1d Ethernet Bridging"
>  	select LLC
>  	select STP
> +	depends on IPV6 || IPV6=n
>  	---help---
>  	  If you say Y here, then your Linux box will be able to act as an
>  	  Ethernet bridge, which means that the different Ethernet segments it