[kbuild:kbuild-next-unstable 25/32] WARNING: modpost: vmlinux: section mismatch in reference: tcp4_net_ops.llvm.4527429266264891517+0x8 (section: .data) -> tcp4_proc_init_net (section: .init.text)

[kbuild:kbuild-next-unstable 25/32] WARNING: modpost: vmlinux: section mismatch in reference: tcp4_net_ops.llvm.4527429266264891517+0x8 (section: .data) -> tcp4_proc_init_net (section: .init.text)

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux.git kbuild-next-unstable
head:   7158c5b67e92e52c2ca9a3617a7e768a84031da1
commit: 9f2aee8f7d1842be08da860e45265d30dba0d1f7 [25/32] kbuild: distributed build support for Clang ThinLTO
config: i386-randconfig-r122-20260611 (https://download.01.org/0day-ci/archive/20260611/202606111233.kM8oo8Df-lkp@intel.com/config)
compiler: clang version 22.1.3 (https://github.com/llvm/llvm-project e9846648fd6183ee6d8cbdb4502213fcf902a211)
sparse: v0.6.5-rc1
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260611/202606111233.kM8oo8Df-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202606111233.kM8oo8Df-lkp@intel.com/

All warnings (new ones prefixed by >>, old ones prefixed by <<):

>> WARNING: modpost: vmlinux: section mismatch in reference: tcp4_net_ops.llvm.4527429266264891517+0x8 (section: .data) -> tcp4_proc_init_net (section: .init.text)
>> WARNING: modpost: vmlinux: section mismatch in reference: udp4_net_ops.llvm.17425824324074326067+0x8 (section: .data) -> udp4_proc_init_net (section: .init.text)
>> WARNING: modpost: vmlinux: section mismatch in reference: ping_v4_net_ops.llvm.5641696707737373282+0x8 (section: .data) -> ping_v4_proc_init_net (section: .init.text)
>> WARNING: modpost: vmlinux: section mismatch in reference: if6_proc_net_ops.llvm.7870945277386035298+0x8 (section: .data) -> if6_proc_net_init (section: .init.text)
>> WARNING: modpost: vmlinux: section mismatch in reference: ipv6_addr_label_ops.llvm.5745897517271459135+0x8 (section: .data) -> ip6addrlbl_net_init (section: .init.text)
>> WARNING: modpost: vmlinux: section mismatch in reference: ndisc_net_ops.llvm.8806210167060761094+0x8 (section: .data) -> ndisc_net_init (section: .init.text)
>> WARNING: modpost: vmlinux: section mismatch in reference: raw6_net_ops.llvm.3743523335772203324+0x8 (section: .data) -> raw6_init_net (section: .init.text)
>> WARNING: modpost: vmlinux: section mismatch in reference: igmp6_net_ops.llvm.7071106350580158050+0x8 (section: .data) -> igmp6_net_init (section: .init.text)
>> WARNING: modpost: vmlinux: section mismatch in reference: tcpv6_net_ops.llvm.17505177970592326146+0x8 (section: .data) -> tcpv6_net_init (section: .init.text)
>> WARNING: modpost: vmlinux: section mismatch in reference: ip6_flowlabel_net_ops.llvm.6051723423336054316+0x8 (section: .data) -> ip6_flowlabel_proc_init (section: .init.text)
>> WARNING: modpost: vmlinux: section mismatch in reference: ipv6_proc_ops.llvm.7829948594772821810+0x8 (section: .data) -> ipv6_proc_init_net (section: .init.text)

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [kbuild:kbuild-next-unstable 25/32] WARNING: modpost: vmlinux: section mismatch in reference: tcp4_net_ops.llvm.4527429266264891517+0x8 (section: .data) -> tcp4_proc_init_net (section: .init.text)

[Rong Xu]

I looked at these warnings. They are from the distributed ThinLTO
builds. But I believe they were caused by missing section tagging for
the data and functions in these network source files.

We need to patch the following files to eliminate the warnings:
net/ipv4/ping.c
net/ipv4/tcp_ipv4.c
net/ipv4/udp.c
net/ipv6/addrconf.c
net/ipv6/addrlabel.c
net/ipv6/ip6_flowlabel.c
net/ipv6/mcast.c
net/ipv6/ndisc.c
net/ipv6/proc.c
net/ipv6/raw.c
net/ipv6/tcp_ipv6.c

One example patch to fix this:

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 8fc24c3743c5..1244fdf74c3f 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -3318,17 +3318,17 @@ static void __net_exit
tcp4_proc_exit_net(struct net *net)
        remove_proc_entry("tcp", net->proc_net);
 }

-static struct pernet_operations tcp4_net_ops = {
+static struct pernet_operations __net_initdata tcp4_net_ops = {
        .init = tcp4_proc_init_net,
        .exit = tcp4_proc_exit_net,
 };

-int __init tcp4_proc_init(void)
+int __net_init tcp4_proc_init(void)
 {
        return register_pernet_subsys(&tcp4_net_ops);
 }

-void tcp4_proc_exit(void)
+void __net_exit tcp4_proc_exit(void)
 {
        unregister_pernet_subsys(&tcp4_net_ops);
 }

I'll be sending over a patch for people to review.

Thanks,

-Rong


On Wed, Jun 10, 2026 at 9:21 PM kernel test robot <lkp@intel.com> wrote:
>
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux.git kbuild-next-unstable
> head:   7158c5b67e92e52c2ca9a3617a7e768a84031da1
> commit: 9f2aee8f7d1842be08da860e45265d30dba0d1f7 [25/32] kbuild: distributed build support for Clang ThinLTO
> config: i386-randconfig-r122-20260611 (https://download.01.org/0day-ci/archive/20260611/202606111233.kM8oo8Df-lkp@intel.com/config)
> compiler: clang version 22.1.3 (https://github.com/llvm/llvm-project e9846648fd6183ee6d8cbdb4502213fcf902a211)
> sparse: v0.6.5-rc1
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260611/202606111233.kM8oo8Df-lkp@intel.com/reproduce)
>
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202606111233.kM8oo8Df-lkp@intel.com/
>
> All warnings (new ones prefixed by >>, old ones prefixed by <<):
>
> >> WARNING: modpost: vmlinux: section mismatch in reference: tcp4_net_ops.llvm.4527429266264891517+0x8 (section: .data) -> tcp4_proc_init_net (section: .init.text)
> >> WARNING: modpost: vmlinux: section mismatch in reference: udp4_net_ops.llvm.17425824324074326067+0x8 (section: .data) -> udp4_proc_init_net (section: .init.text)
> >> WARNING: modpost: vmlinux: section mismatch in reference: ping_v4_net_ops.llvm.5641696707737373282+0x8 (section: .data) -> ping_v4_proc_init_net (section: .init.text)
> >> WARNING: modpost: vmlinux: section mismatch in reference: if6_proc_net_ops.llvm.7870945277386035298+0x8 (section: .data) -> if6_proc_net_init (section: .init.text)
> >> WARNING: modpost: vmlinux: section mismatch in reference: ipv6_addr_label_ops.llvm.5745897517271459135+0x8 (section: .data) -> ip6addrlbl_net_init (section: .init.text)
> >> WARNING: modpost: vmlinux: section mismatch in reference: ndisc_net_ops.llvm.8806210167060761094+0x8 (section: .data) -> ndisc_net_init (section: .init.text)
> >> WARNING: modpost: vmlinux: section mismatch in reference: raw6_net_ops.llvm.3743523335772203324+0x8 (section: .data) -> raw6_init_net (section: .init.text)
> >> WARNING: modpost: vmlinux: section mismatch in reference: igmp6_net_ops.llvm.7071106350580158050+0x8 (section: .data) -> igmp6_net_init (section: .init.text)
> >> WARNING: modpost: vmlinux: section mismatch in reference: tcpv6_net_ops.llvm.17505177970592326146+0x8 (section: .data) -> tcpv6_net_init (section: .init.text)
> >> WARNING: modpost: vmlinux: section mismatch in reference: ip6_flowlabel_net_ops.llvm.6051723423336054316+0x8 (section: .data) -> ip6_flowlabel_proc_init (section: .init.text)
> >> WARNING: modpost: vmlinux: section mismatch in reference: ipv6_proc_ops.llvm.7829948594772821810+0x8 (section: .data) -> ipv6_proc_init_net (section: .init.text)
>
> --
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests/wiki