============================= WARNING: suspicious RCU usage 5.7.0-rc5-next-20200514-syzkaller #0 Not tainted ----------------------------- drivers/net/hamradio/bpqether.c:149 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by ip/3975: #0: ffffffff8a7bad88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8a7bad88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5458 stack backtrace: CPU: 1 PID: 3975 Comm: ip Not tainted 5.7.0-rc5-next-20200514-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18f/0x20d lib/dump_stack.c:118 bpq_get_ax25_dev drivers/net/hamradio/bpqether.c:149 [inline] bpq_device_event+0x796/0x8ee drivers/net/hamradio/bpqether.c:538 notifier_call_chain+0xc0/0x230 kernel/notifier.c:83 call_netdevice_notifiers_info net/core/dev.c:2016 [inline] call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2001 call_netdevice_notifiers_extack net/core/dev.c:2028 [inline] call_netdevice_notifiers net/core/dev.c:2042 [inline] __dev_notify_flags+0x121/0x2c0 net/core/dev.c:8279 dev_change_flags+0x100/0x160 net/core/dev.c:8317 do_setlink+0xa1c/0x35d0 net/core/rtnetlink.c:2605 __rtnl_newlink+0xad0/0x1590 net/core/rtnetlink.c:3273 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3398 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5461 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2469 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 ____sys_sendmsg+0x6e6/0x810 net/socket.c:2352 ___sys_sendmsg+0x100/0x170 net/socket.c:2406 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2439 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x7f93d9e8ddc7 Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb cd 66 0f 1f 44 00 00 8b 05 4a 49 2b 00 85 c0 75 2e 48 63 ff 48 63 d2 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 8b 15 a1 f0 2a 00 f7 d8 64 89 02 48 RSP: 002b:00007fff76f68928 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000005ebe89c6 RCX: 00007f93d9e8ddc7 RDX: 0000000000000000 RSI: 00007fff76f68970 RDI: 0000000000000003 RBP: 00007fff76f68970 R08: 0000000000001000 R09: fefefeff77686d74 R10: 00000000000005e9 R11: 0000000000000246 R12: 00007fff76f689b0 R13: 0000561af72a13c0 R14: 00007fff76f70a30 R15: 0000000000000000 ip (3975) used greatest stack depth: 23208 bytes left