On 11/13/16, 11:59 AM, David Lebrun wrote: > On 11/13/2016 06:23 AM, David Miller wrote: >> This seems like such a huge mess, quite frankly. >> >> IPV6-SR has so many strange dependencies, a weird Kconfig option that is >> simply controlling what a responsible sysadmin should be allow to do if >> he chooses anyways. >> >> Every distribution is going to say "¯\_(ツ)_/¯" and just turn the thing >> on in their builds. > Indeed, the issue is that seg6_iptunnel.o was included in obj-y instead > of ipv6-y, triggering the bug when CONFIG_IPV6=m. Fixed with the > following modification to the patch (tested with allyesconfig and > allmodconfig): > > diff --git a/net/ipv6/Makefile b/net/ipv6/Makefile > index 8979d53..a233136 100644 > --- a/net/ipv6/Makefile > +++ b/net/ipv6/Makefile > @@ -53,6 +53,6 @@ obj-$(subst m,y,$(CONFIG_IPV6)) += inet6_hashtables.o > > ifneq ($(CONFIG_IPV6),) > obj-$(CONFIG_NET_UDP_TUNNEL) += ip6_udp_tunnel.o > -obj-$(CONFIG_LWTUNNEL) += seg6_iptunnel.o > +ipv6-$(CONFIG_LWTUNNEL) += seg6_iptunnel.o > obj-y += mcast_snoop.o > endif
> > I agree with you that the way to combine the dependencies is strange, > even if they are very few. The part of the IPv6-SR patch that is enabled > by default depends on two things: IPV6 and LWTUNNEL. The problem is that > LWTUNNEL does not depend on IPV6 and is not necessarily enabled. To fix > the bug reported by Lorenzo, I propose to select one the three following > solutions: > > 1. Make LWTUNNEL always enabled (removing the option). > Pros: remove an option > Cons: add always-enabled code > > 2. Create an option IPV6_SEG6_LWTUNNEL, which would select LWTUNNEL and > enable the compilation of seg6_iptunnel.o. > Pros: logically dissociate the part of IPv6-SR that depends on > LWTUNNEL from the core patch and simplifies compilation > Cons: add an option I prefer option b). most LWTUNNEL encaps are done this way. seg6 and seg6_iptunnel is new segment routing code and can be under CONFIG_IPV6_SEG6 which depends on CONFIG_LWTUNNEL and CONFIG_IPV6. CONFIG_IPV6_SEG6_HMAC could then depend on CONFIG_IPV6_SEG6 > > 3. Apply the proposed patch with the fix > Pros: do not modify options > Cons: weird conditional compilation > > What do you think ? > > David >
