Greetings, 0day kernel testing robot got the below dmesg and the first bad commit is https://github.com/0day-ci/linux/commits/Paolo-Abeni/udp-full-early-demux... commit 1716a78c09ad52bb98bc0d1aae20539e18313ab0 Author: Paolo Abeni <pabeni(a)redhat.com&gt; AuthorDate: Fri Sep 22 23:06:32 2017 +0200 Commit: 0day robot <fengguang.wu(a)intel.com&gt; CommitDate: Thu Sep 28 06:16:47 2017 +0800 net: implement local route cache inside ifaddr add storage and helpers to associate an ipv{4,6} address with the local route to self. This will be used by a later patch to implement early demux for unconnected UDP sockets. The caches are filled on address creation, with DST_OBSOLETE_NONE. Ipv6 cache are explicitly clearered and refreshed on underlaying device down/up events. The above schema is simpler than refreshing the cache every time the dst expires under the default obsolete schema. Signed-off-by: Paolo Abeni <pabeni(a)redhat.com&gt; 476c557dd9 ipv6/addrconf: add an helper for inet6 address lookup 1716a78c09 net: implement local route cache inside ifaddr e752f6cab0 udp: dst lookup in early demux for unconnected sockets +---------------------------------------------------------------------+------------+------------+------------+ | | 476c557dd9 | 1716a78c09 | e752f6cab0 | +---------------------------------------------------------------------+------------+------------+------------+ | boot_successes | 39 | 0 | 0 | | boot_failures | 0 | 30 | 43 | | WARNING:suspicious_RCU_usage | 0 | 30 | 43 | | include/linux/inetdevice.h:#suspicious_rcu_dereference_check()usage | 0 | 30 | 43 | +---------------------------------------------------------------------+------------+------------+------------+ [ 15.594743] init: Temporary process spawn error: No such file or directory [ 15.614696] init: Failed to create pty - disabling logging for job [ 15.620077] init: Temporary process spawn error: No such file or directory [ 15.633501] [ 15.634151] ============================= [ 15.634153] WARNING: suspicious RCU usage [ 15.634156] 4.14.0-rc1-00617-g1716a78 #118 Not tainted [ 15.634157] ----------------------------- [ 15.634160] include/linux/inetdevice.h:218 suspicious rcu_dereference_check() usage! [ 15.634161] [ 15.634161] other info that might help us debug this: [ 15.634161] [ 15.634163] [ 15.634163] rcu_scheduler_active = 2, debug_locks = 1 [ 15.634166] 1 lock held by ip/3249: [ 15.634167] #0: (rtnl_mutex){+.+.}, at: [<ffffffffb9c47cca>] rtnl_lock+0x17/0x19 [ 15.634180] [ 15.634180] stack backtrace: [ 15.634183] CPU: 0 PID: 3249 Comm: ip Not tainted 4.14.0-rc1-00617-g1716a78 #118 [ 15.634185] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-20161025_171302-gandalf 04/01/2014 [ 15.634187] Call Trace: [ 15.634192] dump_stack+0x86/0xc0 [ 15.634198] lockdep_rcu_suspicious+0xea/0xf3 [ 15.634203] ip_local_route_alloc+0x5e/0xad [ 15.634209] __inet_insert_ifa+0x1f7/0x220 [ 15.634215] inet_insert_ifa+0x12/0x14 [ 15.634218] inetdev_event+0x1ef/0x453 [ 15.634225] notifier_call_chain+0x63/0x8a [ 15.634228] ? notifier_call_chain+0x63/0x8a [ 15.634253] raw_notifier_call_chain+0x14/0x16 [ 15.634258] call_netdevice_notifiers_info+0x52/0x59 [ 15.634262] call_netdevice_notifiers+0x13/0x15 [ 15.634265] __dev_notify_flags+0x53/0x81 [ 15.634269] dev_change_flags+0x4d/0x58 [ 15.634274] do_setlink+0x2e0/0xafa [ 15.634278] ? __lock_acquire+0x80b/0x822 [ 15.634284] ? kvm_sched_clock_read+0x9/0x12 [ 15.634290] ? deactivate_slab+0x646/0x696 [ 15.634293] ? update_stack_state+0x10b/0x15a [ 15.634297] ? update_stack_state+0x10b/0x15a [ 15.634302] rtnl_newlink+0x3ef/0x749 [ 15.634305] ? netdev_master_upper_dev_get+0x12/0x5c [ 15.634308] ? rtnl_newlink+0x118/0x749 [ 15.634314] ? rtnetlink_rcv+0x15/0x17 [ 15.634319] ? save_stack_trace+0x2/0x1d [ 15.634322] ? __lock_acquire+0x80b/0x822 [ 15.634345] rtnetlink_rcv_msg+0x459/0x4d3 [ 15.634350] ? netlink_deliver_tap+0x13d/0x27c [ 15.634353] ? rtnl_calcit+0x187/0x187 [ 15.634357] netlink_rcv_skb+0x5f/0xab [ 15.634363] rtnetlink_rcv+0x15/0x17 [ 15.634365] netlink_unicast+0x102/0x18f [ 15.634371] netlink_sendmsg+0x2ec/0x2fd [ 15.634378] sock_sendmsg+0x17/0x22 [ 15.634381] ___sys_sendmsg+0x1ad/0x22f [ 15.634389] ? do_wp_page+0x4e6/0x4ef [ 15.634398] ? __do_page_fault+0x44f/0x4f4 [ 15.634407] __sys_sendmsg+0x45/0x66 [ 15.634410] ? __sys_sendmsg+0x45/0x66 [ 15.634418] SyS_sendmsg+0x12/0x1c [ 15.634422] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 15.634424] RIP: 0033:0x7fc8caf0b630 [ 15.634426] RSP: 002b:00007ffcb646a738 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 15.634429] RAX: ffffffffffffffda RBX: 0000000000000046 RCX: 00007fc8caf0b630 [ 15.634431] RDX: 0000000000000000 RSI: 00007ffcb646a770 RDI: 0000000000000003 [ 15.634433] RBP: 0000000000000000 R08: 0000000000000000 R09: fefefeff2f736872 [ 15.634435] R10: 00007ffcb646a4d0 R11: 0000000000000246 R12: 00007ffcb646f010 [ 15.634437] R13: 0000000000000000 R14: 00007ffcb646e818 R15: 00007ffcb646f028 [ 15.638080] ip (3249) used greatest stack depth: 11416 bytes left [ 15.842576] init: failsafe main process (3246) killed by TERM signal [ 16.021940] init: Failed to create pty - disabling logging for job # HH:MM RESULT GOOD BAD GOOD_BUT_DIRTY DIRTY_NOT_BAD git bisect start e752f6cab0117395dd6ec24e9f1ceb939049e23b 14a0d032f4ecd9a82294665bd65b4a0480496198 -- git bisect good 81b215513ca2d22cdde89adbf7ba5e73009284f4 # 07:32 G 11 0 0 0 udp: perform full socket lookup in early demux git bisect bad 1716a78c09ad52bb98bc0d1aae20539e18313ab0 # 07:46 B 0 11 50 14 net: implement local route cache inside ifaddr git bisect good 34082254244bcb22f7694ac75ac6788eb793f8db # 07:49 G 11 0 0 0 ip/route: factor out helper for local route creation git bisect good 476c557dd9d7054584d7b044d56ae5847d6181c3 # 07:51 G 11 0 0 0 ipv6/addrconf: add an helper for inet6 address lookup # first bad commit: [1716a78c09ad52bb98bc0d1aae20539e18313ab0] net: implement local route cache inside ifaddr git bisect good 476c557dd9d7054584d7b044d56ae5847d6181c3 # 07:54 G 31 0 0 0 ipv6/addrconf: add an helper for inet6 address lookup # extra tests on HEAD of linux-review/Paolo-Abeni/udp-full-early-demux-for-unconnected-sockets/20170928-061644 git bisect bad e752f6cab0117395dd6ec24e9f1ceb939049e23b # 07:54 B 0 43 100 0 udp: dst lookup in early demux for unconnected sockets # extra tests on tree/branch linux-review/Paolo-Abeni/udp-full-early-demux-for-unconnected-sockets/20170928-061644 git bisect bad e752f6cab0117395dd6ec24e9f1ceb939049e23b # 07:54 B 0 43 100 0 udp: dst lookup in early demux for unconnected sockets # extra tests with first bad commit reverted --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/lkp Intel Corporation