[syzbot] WARNING: suspicious RCU usage in add_v4_addrs

[syzbot <syzbot+27aad254a5e7479997ed@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    0966d385830d riscv: Fix auipc+jalr relocation range checks
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git fixes
console output: https://syzkaller.appspot.com/x/log.txt?x=17b4436a080000
kernel config:  https://syzkaller.appspot.com/x/.config?x=6295d67591064921
dashboard link: https://syzkaller.appspot.com/bug?extid=27aad254a5e7479997ed
compiler:       riscv64-linux-gnu-gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: riscv64

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+27aad254a5e7479997ed@syzkaller.appspotmail.com

=============================
WARNING: suspicious RCU usage
5.17.0-rc1-syzkaller-00002-g0966d385830d #0 Not tainted
-----------------------------
net/ipv6/addrconf.c:3140 suspicious rcu_dereference_protected() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
1 lock held by syz-executor.1/2048:
 #0: 000000c00135d600 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: 000000c00135d600 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x2fe/0x9a0 net/core/rtnetlink.c:5589

stack backtrace:
CPU: 0 PID: 2048 Comm: syz-executor.1 Not tainted 5.17.0-rc1-syzkaller-00002-g0966d385830d #0
Hardware name: riscv-virtio,qemu (DT)
Call Trace:
[<ffffffff8000a228>] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:113
[<ffffffff831668cc>] show_stack+0x34/0x40 arch/riscv/kernel/stacktrace.c:119
[<ffffffff831756ba>] __dump_stack lib/dump_stack.c:88 [inline]
[<ffffffff831756ba>] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:106
[<ffffffff83175742>] dump_stack+0x1c/0x24 lib/dump_stack.c:113
[<ffffffff831689d2>] lockdep_rcu_suspicious+0x106/0x118 kernel/locking/lockdep.c:6563
[<ffffffff82d414d0>] add_v4_addrs+0x566/0x640 net/ipv6/addrconf.c:3140
[<ffffffff82d4e322>] addrconf_gre_config net/ipv6/addrconf.c:3425 [inline]
[<ffffffff82d4e322>] addrconf_notify+0x784/0x1360 net/ipv6/addrconf.c:3605
[<ffffffff800aac84>] notifier_call_chain+0xb8/0x188 kernel/notifier.c:84
[<ffffffff800aad7e>] raw_notifier_call_chain+0x2a/0x38 kernel/notifier.c:392
[<ffffffff8271d086>] call_netdevice_notifiers_info+0x9e/0x10c net/core/dev.c:1919
[<ffffffff827422c8>] call_netdevice_notifiers_extack net/core/dev.c:1931 [inline]
[<ffffffff827422c8>] call_netdevice_notifiers net/core/dev.c:1945 [inline]
[<ffffffff827422c8>] __dev_notify_flags+0x108/0x1fa net/core/dev.c:8179
[<ffffffff827436f6>] dev_change_flags+0x9c/0xba net/core/dev.c:8215
[<ffffffff82767e16>] do_setlink+0x5d6/0x21c4 net/core/rtnetlink.c:2729
[<ffffffff8276a6a2>] __rtnl_newlink+0x99e/0xfa0 net/core/rtnetlink.c:3412
[<ffffffff8276ad04>] rtnl_newlink+0x60/0x8c net/core/rtnetlink.c:3527
[<ffffffff8276b46c>] rtnetlink_rcv_msg+0x338/0x9a0 net/core/rtnetlink.c:5592
[<ffffffff8296ded2>] netlink_rcv_skb+0xf8/0x2be net/netlink/af_netlink.c:2494
[<ffffffff827624f4>] rtnetlink_rcv+0x26/0x30 net/core/rtnetlink.c:5610
[<ffffffff8296cbcc>] netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
[<ffffffff8296cbcc>] netlink_unicast+0x40e/0x5fe net/netlink/af_netlink.c:1343
[<ffffffff8296d29c>] netlink_sendmsg+0x4e0/0x994 net/netlink/af_netlink.c:1919
[<ffffffff826d264e>] sock_sendmsg_nosec net/socket.c:705 [inline]
[<ffffffff826d264e>] sock_sendmsg+0xa0/0xc4 net/socket.c:725
[<ffffffff826d7026>] __sys_sendto+0x1f2/0x2e0 net/socket.c:2040
[<ffffffff826d7152>] __do_sys_sendto net/socket.c:2052 [inline]
[<ffffffff826d7152>] sys_sendto+0x3e/0x52 net/socket.c:2048
[<ffffffff80005716>] ret_from_syscall+0x0/0x2

=============================
WARNING: suspicious RCU usage
5.17.0-rc1-syzkaller-00002-g0966d385830d #0 Not tainted
-----------------------------
include/linux/inetdevice.h:249 suspicious rcu_dereference_protected() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
1 lock held by syz-executor.1/2048:
 #0: 000000c00135d600 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: 000000c00135d600 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x2fe/0x9a0 net/core/rtnetlink.c:5589

stack backtrace:
CPU: 0 PID: 2048 Comm: syz-executor.1 Not tainted 5.17.0-rc1-syzkaller-00002-g0966d385830d #0
Hardware name: riscv-virtio,qemu (DT)
Call Trace:
[<ffffffff8000a228>] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:113
[<ffffffff831668cc>] show_stack+0x34/0x40 arch/riscv/kernel/stacktrace.c:119
[<ffffffff831756ba>] __dump_stack lib/dump_stack.c:88 [inline]
[<ffffffff831756ba>] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:106
[<ffffffff83175742>] dump_stack+0x1c/0x24 lib/dump_stack.c:113
[<ffffffff831689d2>] lockdep_rcu_suspicious+0x106/0x118 kernel/locking/lockdep.c:6563
[<ffffffff82d412fe>] __in_dev_get_rtnl include/linux/inetdevice.h:249 [inline]
[<ffffffff82d412fe>] add_v4_addrs+0x394/0x640 net/ipv6/addrconf.c:3135
[<ffffffff82d4e322>] addrconf_gre_config net/ipv6/addrconf.c:3425 [inline]
[<ffffffff82d4e322>] addrconf_notify+0x784/0x1360 net/ipv6/addrconf.c:3605
[<ffffffff800aac84>] notifier_call_chain+0xb8/0x188 kernel/notifier.c:84
[<ffffffff800aad7e>] raw_notifier_call_chain+0x2a/0x38 kernel/notifier.c:392
[<ffffffff8271d086>] call_netdevice_notifiers_info+0x9e/0x10c net/core/dev.c:1919
[<ffffffff827422c8>] call_netdevice_notifiers_extack net/core/dev.c:1931 [inline]
[<ffffffff827422c8>] call_netdevice_notifiers net/core/dev.c:1945 [inline]
[<ffffffff827422c8>] __dev_notify_flags+0x108/0x1fa net/core/dev.c:8179
[<ffffffff827436f6>] dev_change_flags+0x9c/0xba net/core/dev.c:8215
[<ffffffff82767e16>] do_setlink+0x5d6/0x21c4 net/core/rtnetlink.c:2729
[<ffffffff8276a6a2>] __rtnl_newlink+0x99e/0xfa0 net/core/rtnetlink.c:3412
[<ffffffff8276ad04>] rtnl_newlink+0x60/0x8c net/core/rtnetlink.c:3527
[<ffffffff8276b46c>] rtnetlink_rcv_msg+0x338/0x9a0 net/core/rtnetlink.c:5592
[<ffffffff8296ded2>] netlink_rcv_skb+0xf8/0x2be net/netlink/af_netlink.c:2494
[<ffffffff827624f4>] rtnetlink_rcv+0x26/0x30 net/core/rtnetlink.c:5610
[<ffffffff8296cbcc>] netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
[<ffffffff8296cbcc>] netlink_unicast+0x40e/0x5fe net/netlink/af_netlink.c:1343
[<ffffffff8296d29c>] netlink_sendmsg+0x4e0/0x994 net/netlink/af_netlink.c:1919
[<ffffffff826d264e>] sock_sendmsg_nosec net/socket.c:705 [inline]
[<ffffffff826d264e>] sock_sendmsg+0xa0/0xc4 net/socket.c:725
[<ffffffff826d7026>] __sys_sendto+0x1f2/0x2e0 net/socket.c:2040
[<ffffffff826d7152>] __do_sys_sendto net/socket.c:2052 [inline]
[<ffffffff826d7152>] sys_sendto+0x3e/0x52 net/socket.c:2048
[<ffffffff80005716>] ret_from_syscall+0x0/0x2

=============================
WARNING: suspicious RCU usage
5.17.0-rc1-syzkaller-00002-g0966d385830d #0 Not tainted
-----------------------------
net/ipv6/addrconf.c:3140 suspicious rcu_dereference_protected() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
1 lock held by syz-executor.1/2048:
 #0: 000000c00135d600 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: 000000c00135d600 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x2fe/0x9a0 net/core/rtnetlink.c:5589

stack backtrace:
CPU: 0 PID: 2048 Comm: syz-executor.1 Not tainted 5.17.0-rc1-syzkaller-00002-g0966d385830d #0
Hardware name: riscv-virtio,qemu (DT)
Call Trace:
[<ffffffff8000a228>] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:113
[<ffffffff831668cc>] show_stack+0x34/0x40 arch/riscv/kernel/stacktrace.c:119
[<ffffffff831756ba>] __dump_stack lib/dump_stack.c:88 [inline]
[<ffffffff831756ba>] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:106
[<ffffffff83175742>] dump_stack+0x1c/0x24 lib/dump_stack.c:113
[<ffffffff831689d2>] lockdep_rcu_suspicious+0x106/0x118 kernel/locking/lockdep.c:6563
[<ffffffff82d4154c>] add_v4_addrs+0x5e2/0x640 net/ipv6/addrconf.c:3140
[<ffffffff82d4e322>] addrconf_gre_config net/ipv6/addrconf.c:3425 [inline]
[<ffffffff82d4e322>] addrconf_notify+0x784/0x1360 net/ipv6/addrconf.c:3605
[<ffffffff800aac84>] notifier_call_chain+0xb8/0x188 kernel/notifier.c:84
[<ffffffff800aad7e>] raw_notifier_call_chain+0x2a/0x38 kernel/notifier.c:392
[<ffffffff8271d086>] call_netdevice_notifiers_info+0x9e/0x10c net/core/dev.c:1919
[<ffffffff827422c8>] call_netdevice_notifiers_extack net/core/dev.c:1931 [inline]
[<ffffffff827422c8>] call_netdevice_notifiers net/core/dev.c:1945 [inline]
[<ffffffff827422c8>] __dev_notify_flags+0x108/0x1fa net/core/dev.c:8179
[<ffffffff827436f6>] dev_change_flags+0x9c/0xba net/core/dev.c:8215
[<ffffffff82767e16>] do_setlink+0x5d6/0x21c4 net/core/rtnetlink.c:2729
[<ffffffff8276a6a2>] __rtnl_newlink+0x99e/0xfa0 net/core/rtnetlink.c:3412
[<ffffffff8276ad04>] rtnl_newlink+0x60/0x8c net/core/rtnetlink.c:3527
[<ffffffff8276b46c>] rtnetlink_rcv_msg+0x338/0x9a0 net/core/rtnetlink.c:5592
[<ffffffff8296ded2>] netlink_rcv_skb+0xf8/0x2be net/netlink/af_netlink.c:2494
[<ffffffff827624f4>] rtnetlink_rcv+0x26/0x30 net/core/rtnetlink.c:5610
[<ffffffff8296cbcc>] netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
[<ffffffff8296cbcc>] netlink_unicast+0x40e/0x5fe net/netlink/af_netlink.c:1343
[<ffffffff8296d29c>] netlink_sendmsg+0x4e0/0x994 net/netlink/af_netlink.c:1919
[<ffffffff826d264e>] sock_sendmsg_nosec net/socket.c:705 [inline]
[<ffffffff826d264e>] sock_sendmsg+0xa0/0xc4 net/socket.c:725
[<ffffffff826d7026>] __sys_sendto+0x1f2/0x2e0 net/socket.c:2040
[<ffffffff826d7152>] __do_sys_sendto net/socket.c:2052 [inline]
[<ffffffff826d7152>] sys_sendto+0x3e/0x52 net/socket.c:2048
[<ffffffff80005716>] ret_from_syscall+0x0/0x2

=============================
WARNING: suspicious RCU usage
5.17.0-rc1-syzkaller-00002-g0966d385830d #0 Not tainted
-----------------------------
include/net/addrconf.h:313 suspicious rcu_dereference_check() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
1 lock held by syz-executor.1/2048:
 #0: 000000c00135d600 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: 000000c00135d600 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x2fe/0x9a0 net/core/rtnetlink.c:5589

stack backtrace:
CPU: 0 PID: 2048 Comm: syz-executor.1 Not tainted 5.17.0-rc1-syzkaller-00002-g0966d385830d #0
Hardware name: riscv-virtio,qemu (DT)
Call Trace:
[<ffffffff8000a228>] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:113
[<ffffffff831668cc>] show_stack+0x34/0x40 arch/riscv/kernel/stacktrace.c:119
[<ffffffff831756ba>] __dump_stack lib/dump_stack.c:88 [inline]
[<ffffffff831756ba>] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:106
[<ffffffff83175742>] dump_stack+0x1c/0x24 lib/dump_stack.c:113
[<ffffffff831689d2>] lockdep_rcu_suspicious+0x106/0x118 kernel/locking/lockdep.c:6563
[<ffffffff82db8b04>] __in6_dev_get include/net/addrconf.h:313 [inline]
[<ffffffff82db8b04>] __in6_dev_get include/net/addrconf.h:311 [inline]
[<ffffffff82db8b04>] ipv6_mc_netdev_event+0x29c/0x4a8 net/ipv6/mcast.c:2842
[<ffffffff800aac84>] notifier_call_chain+0xb8/0x188 kernel/notifier.c:84
[<ffffffff800aad7e>] raw_notifier_call_chain+0x2a/0x38 kernel/notifier.c:392
[<ffffffff8271d086>] call_netdevice_notifiers_info+0x9e/0x10c net/core/dev.c:1919
[<ffffffff827422c8>] call_netdevice_notifiers_extack net/core/dev.c:1931 [inline]
[<ffffffff827422c8>] call_netdevice_notifiers net/core/dev.c:1945 [inline]
[<ffffffff827422c8>] __dev_notify_flags+0x108/0x1fa net/core/dev.c:8179
[<ffffffff827436f6>] dev_change_flags+0x9c/0xba net/core/dev.c:8215
[<ffffffff82767e16>] do_setlink+0x5d6/0x21c4 net/core/rtnetlink.c:2729
[<ffffffff8276a6a2>] __rtnl_newlink+0x99e/0xfa0 net/core/rtnetlink.c:3412
[<ffffffff8276ad04>] rtnl_newlink+0x60/0x8c net/core/rtnetlink.c:3527
[<ffffffff8276b46c>] rtnetlink_rcv_msg+0x338/0x9a0 net/core/rtnetlink.c:5592
[<ffffffff8296ded2>] netlink_rcv_skb+0xf8/0x2be net/netlink/af_netlink.c:2494
[<ffffffff827624f4>] rtnetlink_rcv+0x26/0x30 net/core/rtnetlink.c:5610
[<ffffffff8296cbcc>] netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
[<ffffffff8296cbcc>] netlink_unicast+0x40e/0x5fe net/netlink/af_netlink.c:1343
[<ffffffff8296d29c>] netlink_sendmsg+0x4e0/0x994 net/netlink/af_netlink.c:1919
[<ffffffff826d264e>] sock_sendmsg_nosec net/socket.c:705 [inline]
[<ffffffff826d264e>] sock_sendmsg+0xa0/0xc4 net/socket.c:725
[<ffffffff826d7026>] __sys_sendto+0x1f2/0x2e0 net/socket.c:2040
[<ffffffff826d7152>] __do_sys_sendto net/socket.c:2052 [inline]
[<ffffffff826d7152>] sys_sendto+0x3e/0x52 net/socket.c:2048
[<ffffffff80005716>] ret_from_syscall+0x0/0x2

=============================
WARNING: suspicious RCU usage
5.17.0-rc1-syzkaller-00002-g0966d385830d #0 Not tainted
-----------------------------
net/8021q/vlan.c:392 suspicious rcu_dereference_protected() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
1 lock held by syz-executor.1/2048:
 #0: 000000c00135d600 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: 000000c00135d600 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x2fe/0x9a0 net/core/rtnetlink.c:5589

stack backtrace:
CPU: 0 PID: 2048 Comm: syz-executor.1 Not tainted 5.17.0-rc1-syzkaller-00002-g0966d385830d #0
Hardware name: riscv-virtio,qemu (DT)
Call Trace:
[<ffffffff8000a228>] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:113
[<ffffffff831668cc>] show_stack+0x34/0x40 arch/riscv/kernel/stacktrace.c:119
[<ffffffff831756ba>] __dump_stack lib/dump_stack.c:88 [inline]
[<ffffffff831756ba>] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:106
[<ffffffff83175742>] dump_stack+0x1c/0x24 lib/dump_stack.c:113
[<ffffffff831689d2>] lockdep_rcu_suspicious+0x106/0x118 kernel/locking/lockdep.c:6563
[<ffffffff82f0e32e>] vlan_device_event+0x364/0x1434 net/8021q/vlan.c:392
[<ffffffff800aac84>] notifier_call_chain+0xb8/0x188 kernel/notifier.c:84
[<ffffffff800aad7e>] raw_notifier_call_chain+0x2a/0x38 kernel/notifier.c:392
[<ffffffff8271d086>] call_netdevice_notifiers_info+0x9e/0x10c net/core/dev.c:1919
[<ffffffff827422c8>] call_netdevice_notifiers_extack net/core/dev.c:1931 [inline]
[<ffffffff827422c8>] call_netdevice_notifiers net/core/dev.c:1945 [inline]
[<ffffffff827422c8>] __dev_notify_flags+0x108/0x1fa net/core/dev.c:8179
[<ffffffff827436f6>] dev_change_flags+0x9c/0xba net/core/dev.c:8215
[<ffffffff82767e16>] do_setlink+0x5d6/0x21c4 net/core/rtnetlink.c:2729
[<ffffffff8276a6a2>] __rtnl_newlink+0x99e/0xfa0 net/core/rtnetlink.c:3412
[<ffffffff8276ad04>] rtnl_newlink+0x60/0x8c net/core/rtnetlink.c:3527
[<ffffffff8276b46c>] rtnetlink_rcv_msg+0x338/0x9a0 net/core/rtnetlink.c:5592
[<ffffffff8296ded2>] netlink_rcv_skb+0xf8/0x2be net/netlink/af_netlink.c:2494
[<ffffffff827624f4>] rtnetlink_rcv+0x26/0x30 net/core/rtnetlink.c:5610
[<ffffffff8296cbcc>] netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
[<ffffffff8296cbcc>] netlink_unicast+0x40e/0x5fe net/netlink/af_netlink.c:1343
[<ffffffff8296d29c>] netlink_sendmsg+0x4e0/0x994 net/netlink/af_netlink.c:1919
[<ffffffff826d264e>] sock_sendmsg_nosec net/socket.c:705 [inline]
[<ffffffff826d264e>] sock_sendmsg+0xa0/0xc4 net/socket.c:725
[<ffffffff826d7026>] __sys_sendto+0x1f2/0x2e0 net/socket.c:2040
[<ffffffff826d7152>] __do_sys_sendto net/socket.c:2052 [inline]
[<ffffffff826d7152>] sys_sendto+0x3e/0x52 net/socket.c:2048
[<ffffffff80005716>] ret_from_syscall+0x0/0x2

=====================================
WARNING: bad unlock balance detected!
5.17.0-rc1-syzkaller-00002-g0966d385830d #0 Not tainted
-------------------------------------
syz-executor.1/2048 is trying to release lock (rtnl_mutex) at:
[<ffffffff827745dc>] __rtnl_unlock+0x34/0x80 net/core/rtnetlink.c:98
but there are no more locks to release!

other info that might help us debug this:
1 lock held by syz-executor.1/2048:
 #0: 000000c00135d600 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: 000000c00135d600 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x2fe/0x9a0 net/core/rtnetlink.c:5589

stack backtrace:
CPU: 0 PID: 2048 Comm: syz-executor.1 Not tainted 5.17.0-rc1-syzkaller-00002-g0966d385830d #0
Hardware name: riscv-virtio,qemu (DT)
Call Trace:
[<ffffffff8000a228>] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:113
[<ffffffff831668cc>] show_stack+0x34/0x40 arch/riscv/kernel/stacktrace.c:119
[<ffffffff831756ba>] __dump_stack lib/dump_stack.c:88 [inline]
[<ffffffff831756ba>] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:106
[<ffffffff83175742>] dump_stack+0x1c/0x24 lib/dump_stack.c:113
[<ffffffff8316887a>] print_unlock_imbalance_bug.part.0+0xc4/0xd2 kernel/locking/lockdep.c:5080
[<ffffffff80115d78>] print_unlock_imbalance_bug kernel/locking/lockdep.c:5062 [inline]
[<ffffffff80115d78>] __lock_release kernel/locking/lockdep.c:5316 [inline]
[<ffffffff80115d78>] lock_release+0x4fe/0x614 kernel/locking/lockdep.c:5659
[<ffffffff831a7d4c>] __mutex_unlock_slowpath+0xa4/0x3a2 kernel/locking/mutex.c:893
[<ffffffff831a8058>] mutex_unlock+0xe/0x16 kernel/locking/mutex.c:540
[<ffffffff827745dc>] __rtnl_unlock+0x34/0x80 net/core/rtnetlink.c:98
[<ffffffff82746ef4>] netdev_run_todo+0x1ee/0x752 net/core/dev.c:9929
[<ffffffff8276b47a>] rtnl_unlock net/core/rtnetlink.c:112 [inline]
[<ffffffff8276b47a>] rtnetlink_rcv_msg+0x346/0x9a0 net/core/rtnetlink.c:5593
[<ffffffff8296ded2>] netlink_rcv_skb+0xf8/0x2be net/netlink/af_netlink.c:2494
[<ffffffff827624f4>] rtnetlink_rcv+0x26/0x30 net/core/rtnetlink.c:5610
[<ffffffff8296cbcc>] netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
[<ffffffff8296cbcc>] netlink_unicast+0x40e/0x5fe net/netlink/af_netlink.c:1343
[<ffffffff8296d29c>] netlink_sendmsg+0x4e0/0x994 net/netlink/af_netlink.c:1919
[<ffffffff826d264e>] sock_sendmsg_nosec net/socket.c:705 [inline]
[<ffffffff826d264e>] sock_sendmsg+0xa0/0xc4 net/socket.c:725
[<ffffffff826d7026>] __sys_sendto+0x1f2/0x2e0 net/socket.c:2040
[<ffffffff826d7152>] __do_sys_sendto net/socket.c:2052 [inline]
[<ffffffff826d7152>] sys_sendto+0x3e/0x52 net/socket.c:2048
[<ffffffff80005716>] ret_from_syscall+0x0/0x2
8021q: adding VLAN 0 to HW filter on device bond0


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