tipc: TX() has been purged, node left! ============================= WARNING: suspicious RCU usage 5.7.0-rc2-next-20200421-syzkaller #0 Not tainted ----------------------------- net/ipv4/ipmr.c:1757 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 4 locks held by kworker/u4:1/21: #0: ffff8880a9772138 ((wq_completion)netns){+.+.}-{0:0}, at: __write_once_size include/linux/compiler.h:250 [inline] #0: ffff8880a9772138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880a9772138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8880a9772138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8880a9772138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8880a9772138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8880a9772138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 kernel/workqueue.c:2239 #1: ffffc90000dd7dc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 kernel/workqueue.c:2243 #2: ffffffff8a5a2b70 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 net/core/net_namespace.c:565 #3: ffffffff8a5aeae8 (rtnl_mutex){+.+.}-{3:3}, at: ip6gre_exit_batch_net+0x88/0x700 net/ipv6/ip6_gre.c:1602 stack backtrace: CPU: 1 PID: 21 Comm: kworker/u4:1 Not tainted 5.7.0-rc2-next-20200421-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x188/0x20d lib/dump_stack.c:118 ipmr_device_event+0x240/0x2b0 net/ipv4/ipmr.c:1757 notifier_call_chain+0xc0/0x230 kernel/notifier.c:83 call_netdevice_notifiers_info net/core/dev.c:1948 [inline] call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1933 call_netdevice_notifiers_extack net/core/dev.c:1960 [inline] call_netdevice_notifiers net/core/dev.c:1974 [inline] rollback_registered_many+0x75c/0xe70 net/core/dev.c:8828 unregister_netdevice_many.part.0+0x16/0x1e0 net/core/dev.c:9993 unregister_netdevice_many+0x36/0x50 net/core/dev.c:9992 ip6gre_exit_batch_net+0x4e8/0x700 net/ipv6/ip6_gre.c:1605 ops_exit_list.isra.0+0x103/0x150 net/core/net_namespace.c:189 cleanup_net+0x511/0xa50 net/core/net_namespace.c:603 process_one_work+0x965/0x16a0 kernel/workqueue.c:2268 worker_thread+0x96/0xe20 kernel/workqueue.c:2414 kthread+0x38b/0x470 kernel/kthread.c:274 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352