HI Steffen, We detected this warning in the stable tree. I wonder if it's known issue and if there are fixes in mainline. git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git linux-3.14.y commit 49da0655e28b5bf9d869e1c50c15c990c5db5f94 Author: Steffen Klassert <steffen.klassert(a)secunet.com&gt; AuthorDate: Mon May 19 11:36:56 2014 +0200 Commit: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org&gt; CommitDate: Sat May 31 13:20:39 2014 -0700 ip_tunnel: Initialize the fallback device properly [ Upstream commit 78ff4be45a4c51d8fb21ad92e4fabb467c6c3eeb ] We need to initialize the fallback device to have a correct mtu set on this device. Otherwise the mtu is set to null and the device is unusable. Fixes: fd58156e456d ("IPIP: Use ip-tunneling code.") Cc: Pravin B Shelar <pshelar(a)nicira.com&gt; Signed-off-by: Steffen Klassert <steffen.klassert(a)secunet.com&gt; Signed-off-by: David S. Miller <davem(a)davemloft.net&gt; Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org&gt; +-------------------------------------------------------------------------+------------+------------+----------+ | | 39f95dfd2c | 49da0655e2 | v3.14.24 | +-------------------------------------------------------------------------+------------+------------+----------+ | boot_successes | 60 | 0 | 0 | | boot_failures | 0 | 20 | 42 | | WARNING:at_net/batman-adv/hard-interface.c:batadv_is_on_batman_iface() | 0 | 20 | 10 | | backtrace:register_netdevice_notifier | 0 | 20 | 42 | | backtrace:batadv_init | 0 | 20 | 42 | | backtrace:kernel_init_freeable | 0 | 20 | 42 | | WARNING:at_net/batman-adv/hard-interface.c:#batadv_is_on_batman_iface() | 0 | 0 | 32 | +-------------------------------------------------------------------------+------------+------------+----------+ [ 3.019820] libceph: loaded (mon/osd proto 15/24) [ 3.021215] ------------[ cut here ]------------ [ 3.021215] ------------[ cut here ]------------ [ 3.022447] WARNING: CPU: 0 PID: 1 at net/batman-adv/hard-interface.c:92 batadv_is_on_batman_iface+0x52/0x65() [ 3.022447] WARNING: CPU: 0 PID: 1 at net/batman-adv/hard-interface.c:92 batadv_is_on_batman_iface+0x52/0x65() [ 3.025458] Cannot find parent device [ 3.025458] Cannot find parent device [ 3.026403] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.14.4-00438-g49da065 #27 [ 3.026403] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.14.4-00438-g49da065 #27 [ 3.028383] 0000000000000000 [ 3.028383] 0000000000000000 ffff880011533d48 ffff880011533d48 ffffffff81883d03 ffffffff81883d03 ffff880011533d90 ffff880011533d90 [ 3.030446] ffff880011533d80 [ 3.030446] ffff880011533d80 ffffffff810b3427 ffffffff810b3427 ffffffff8185c842 ffffffff8185c842 0000000000000000 0000000000000000 [ 3.032471] ffff880000170000 [ 3.032471] ffff880000170000 0000000000000005 0000000000000005 ffffffff81e93301 ffffffff81e93301 ffff880011533de8 ffff880011533de8 [ 3.034496] Call Trace: [ 3.034496] Call Trace: [ 3.035145] [<ffffffff81883d03>] dump_stack+0x4d/0x66 [ 3.035145] [<ffffffff81883d03>] dump_stack+0x4d/0x66 [ 3.036494] [<ffffffff810b3427>] warn_slowpath_common+0x70/0x89 [ 3.036494] [<ffffffff810b3427>] warn_slowpath_common+0x70/0x89 [ 3.038086] [<ffffffff8185c842>] ? batadv_is_on_batman_iface+0x52/0x65 [ 3.038086] [<ffffffff8185c842>] ? batadv_is_on_batman_iface+0x52/0x65 [ 3.039803] [<ffffffff810b349d>] warn_slowpath_fmt+0x43/0x4b [ 3.039803] [<ffffffff810b349d>] warn_slowpath_fmt+0x43/0x4b [ 3.041337] [<ffffffff8185c842>] batadv_is_on_batman_iface+0x52/0x65 [ 3.041337] [<ffffffff8185c842>] batadv_is_on_batman_iface+0x52/0x65 [ 3.043039] [<ffffffff8185d2a8>] batadv_hard_if_event+0xbc/0x357 [ 3.043039] [<ffffffff8185d2a8>] batadv_hard_if_event+0xbc/0x357 [ 3.044637] [<ffffffff8170c650>] call_netdevice_notifier+0x12/0x14 [ 3.044637] [<ffffffff8170c650>] call_netdevice_notifier+0x12/0x14 [ 3.046271] [<ffffffff8170f28d>] register_netdevice_notifier+0x83/0x174 [ 3.046271] [<ffffffff8170f28d>] register_netdevice_notifier+0x83/0x174 [ 3.048039] [<ffffffff820f5c6a>] ? batadv_iv_init+0x36/0x36 [ 3.048039] [<ffffffff820f5c6a>] ? batadv_iv_init+0x36/0x36 [ 3.049511] [<ffffffff820f5d62>] batadv_init+0xf8/0x124 [ 3.049511] [<ffffffff820f5d62>] batadv_init+0xf8/0x124 [ 3.050934] [<ffffffff820a7dc4>] do_one_initcall+0x7f/0x110 [ 3.050934] [<ffffffff820a7dc4>] do_one_initcall+0x7f/0x110 [ 3.052446] [<ffffffff810cb000>] ? parse_args+0xe5/0x292 [ 3.052446] [<ffffffff810cb000>] ? parse_args+0xe5/0x292 [ 3.053885] [<ffffffff820a7f81>] kernel_init_freeable+0x12c/0x1af [ 3.053885] [<ffffffff820a7f81>] kernel_init_freeable+0x12c/0x1af [ 3.055509] [<ffffffff8187a083>] ? rest_init+0xc7/0xc7 [ 3.055509] [<ffffffff8187a083>] ? rest_init+0xc7/0xc7 [ 3.056899] [<ffffffff8187a08c>] kernel_init+0x9/0xd5 [ 3.056899] [<ffffffff8187a08c>] kernel_init+0x9/0xd5 [ 3.058250] [<ffffffff8189158c>] ret_from_fork+0x7c/0xb0 [ 3.058250] [<ffffffff8189158c>] ret_from_fork+0x7c/0xb0 [ 3.059647] [<ffffffff8187a083>] ? rest_init+0xc7/0xc7 [ 3.059647] [<ffffffff8187a083>] ? rest_init+0xc7/0xc7 [ 3.061059] ---[ end trace c1c0c6629162e83a ]--- [ 3.061059] ---[ end trace c1c0c6629162e83a ]--- git bisect start 9c3da88145da7cd96bb898bc0304d3f783d4c8b2 455c6fdbd219161bd09b1165f11699d6d73de11c -- git bisect bad 693639e6d5de17cdd5db53f8046a4c6fd275647a # 09:55 0- 20 tty: Correct INPCK handling git bisect bad 6f5d63343a96cfadaa16fd4bcc06c0c7b0b26c7f # 10:11 0- 10 ARM: dts: kirkwood: fix mislocated pcie-controller nodes git bisect good aa0e5094d6c6117d2c3ba65378c61a36984acb53 # 10:18 20+ 0 pinctrl: as3722: fix handling of GPIO invert bit git bisect good 22b2efbb5aa8d97b5f2b7a030dea626d97c87a09 # 10:22 20+ 0 ip_tunnel: Set network header properly for IP_ECN_decapsulate() git bisect bad 6a12f896ce0aa2e88af62b5282b2a40488a5283e # 10:27 0- 20 mac80211: fix on-channel remain-on-channel git bisect bad 7c3b5654c06c68470c446f96c6ba9b939c67771e # 10:30 0- 20 futex: Prevent attaching to kernel threads git bisect good adeb3fe4ef6621793d7f1d6f0b9c9cc88827c5b7 # 10:38 20+ 0 net: avoid dependency of net_get_random_once on nop patching git bisect good 32eb568e09bfdf10bd90c8478e5a79b5f9f3c841 # 10:41 20+ 0 batman-adv: increase orig refcount when storing ref in gw_node git bisect bad ff9cfa6b917a903fe24dba928dca61d0c9339864 # 10:44 0- 20 ipv6: gro: fix CHECKSUM_COMPLETE support git bisect bad 49da0655e28b5bf9d869e1c50c15c990c5db5f94 # 10:44 0- 20 ip_tunnel: Initialize the fallback device properly git bisect good 39f95dfd2c76415d03489aef9674638e00c95055 # 10:44 60+ 0 batman-adv: fix local TT check for outgoing arp requests in DAT # first bad commit: [49da0655e28b5bf9d869e1c50c15c990c5db5f94] ip_tunnel: Initialize the fallback device properly git bisect good 39f95dfd2c76415d03489aef9674638e00c95055 # 10:44 60+ 0 batman-adv: fix local TT check for outgoing arp requests in DAT # extra tests on HEAD of stable/linux-3.14.y git bisect bad 9c3da88145da7cd96bb898bc0304d3f783d4c8b2 # 10:44 0- 42 Linux 3.14.24 # extra tests on tree/branch stable/linux-3.14.y git bisect bad 2dc2565902d3c24108c4b7101e91957fd068a242 # 10:48 0- 2 Linux 3.14.25 # extra tests on tree/branch linus/master git bisect good 5d01410fe4d92081f349b013a2e7a95429e4f2c9 # 10:55 60+ 0 Linux 3.18-rc6 # extra tests on tree/branch next/master git bisect good 7cc2ecdb63cfae062aeadc7c575a02b6e9cc4dbb # 11:05 60+ 60 Add linux-next specific files for 20141125 This script may reproduce the error. ---------------------------------------------------------------------------- #!/bin/bash kernel=$1 initrd=quantal-core-x86_64.cgz wget --no-clobber https://github.com/fengguang/reproduce-kernel-bug/raw/master/initrd/$initrd kvm=( qemu-system-x86_64 -cpu kvm64 -enable-kvm -kernel $kernel -initrd $initrd -m 320 -smp 2 -net nic,vlan=1,model=e1000 -net user,vlan=1 -boot order=nc -no-reboot -watchdog i6300esb -rtc base=localtime -serial stdio -display none -monitor null ) append=( hung_task_panic=1 earlyprintk=ttyS0,115200 debug apic=debug sysrq_always_enabled rcupdate.rcu_cpu_stall_timeout=100 panic=-1 softlockup_panic=1 nmi_watchdog=panic oops=panic load_ramdisk=2 prompt_ramdisk=0 console=ttyS0,115200 console=tty0 vga=normal root=/dev/ram0 rw drbd.minor_count=8 ) "${kvm[@]}" --append "${append[*]}" ---------------------------------------------------------------------------- Thanks, Fengguang _______________________________________________ LKP mailing list LKP(a)linux.intel.com