Florian: I am seeing this warning:
$ make O=kbuild/perf -j 24 -s In file included from /home/dsa/kernel-3.git/include/linux/kernel.h:10:0, from /home/dsa/kernel-3.git/include/linux/list.h:9, from /home/dsa/kernel-3.git/include/linux/module.h:9, from /home/dsa/kernel-3.git/net/xfrm/xfrm_output.c:13: /home/dsa/kernel-3.git/net/xfrm/xfrm_output.c: In function ‘xfrm_output_resume’: /home/dsa/kernel-3.git/include/linux/compiler.h:252:20: warning: array subscript is above array bounds [-Warray-bounds] __read_once_size(&(x), __u.__c, sizeof(x)); \ ^~~~ /home/dsa/kernel-3.git/include/linux/compiler.h:258:22: note: in expansion of macro ‘__READ_ONCE’ #define READ_ONCE(x) __READ_ONCE(x, 1) ^~~~~~~~~~~ /home/dsa/kernel-3.git/include/linux/rcupdate.h:350:48: note: in expansion of macro ‘READ_ONCE’ typeof(*p) *________p1 = (typeof(*p) *__force)READ_ONCE(p); \ ^~~~~~~~~ /home/dsa/kernel-3.git/include/linux/rcupdate.h:487:2: note: in expansion of macro ‘__rcu_dereference_check’ __rcu_dereference_check((p), (c) || rcu_read_lock_held(), __rcu) ^~~~~~~~~~~~~~~~~~~~~~~ /home/dsa/kernel-3.git/include/linux/rcupdate.h:545:28: note: in expansion of macro ‘rcu_dereference_check’ #define rcu_dereference(p) rcu_dereference_check(p, 0) ^~~~~~~~~~~~~~~~~~~~~ /home/dsa/kernel-3.git/include/linux/netfilter.h:218:15: note: in expansion of macro ‘rcu_dereference’ hook_head = rcu_dereference(net->nf.hooks_arp[hook]); ^~~~~~~~~~~~~~~ Line in question is the nf_hook in xfrm_output_resume. NF_INET_POST_ROUTING = 4 which is greater than NF_ARP_NUMHOOKS = 3 I believe ef57170bbfdd6 is the commit that introduced the warning