INFO: task syz-executor.0:15339 blocked for more than 143 seconds. Not tainted 5.7.0-rc5-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D27968 15339 7095 0x00004004 Call Trace: context_switch kernel/sched/core.c:3367 [inline] __schedule+0x937/0x1ff0 kernel/sched/core.c:4083 __sched_text_start+0x8/0x8 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline] test_ti_thread_flag include/linux/thread_info.h:84 [inline] need_resched include/linux/sched.h:1827 [inline] preempt_schedule_common+0x5e/0xc0 kernel/sched/core.c:4247 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:50 schedule+0xd0/0x2a0 kernel/sched/core.c:4158 rwsem_down_write_slowpath+0x706/0xf90 kernel/locking/rwsem.c:1235 rwsem_mark_wake+0x8d0/0x8d0 include/linux/compiler.h:199 arch_local_irq_restore arch/x86/include/asm/paravirt.h:759 [inline] lock_acquire+0x267/0x8f0 kernel/locking/lockdep.c:4937 arch_local_irq_restore arch/x86/include/asm/paravirt.h:759 [inline] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irqrestore+0x8c/0xe0 kernel/locking/spinlock.c:191 lock_release+0x800/0x800 kernel/locking/lockdep.c:4689 trace_hardirqs_on_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:41 __down_write kernel/locking/rwsem.c:1389 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1532 atomic64_try_cmpxchg include/asm-generic/atomic-instrumented.h:1504 [inline] atomic_long_try_cmpxchg_acquire include/asm-generic/atomic-long.h:442 [inline] __down_write kernel/locking/rwsem.c:1387 [inline] down_write+0xb2/0x150 kernel/locking/rwsem.c:1532 __down_write kernel/locking/rwsem.c:1389 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1532 __down_timeout+0x2d0/0x2d0 register_netdevice_notifier+0x1e/0x270 net/core/dev.c:1729 bcm_init+0x1a3/0x210 net/can/bcm.c:1451 canbcm_pernet_init+0x90/0x90 net/can/bcm.c:1677 can_create+0x27c/0x500 net/can/af_can.c:168 __sock_create+0x3cb/0x730 net/socket.c:1433 sock_create net/socket.c:1484 [inline] __sys_socketpair+0x1be/0x560 net/socket.c:1584 __ia32_sys_socket+0xb0/0xb0 net/socket.c:1533 __do_sys_clock_gettime kernel/time/posix-timers.c:1094 [inline] __se_sys_clock_gettime kernel/time/posix-timers.c:1082 [inline] __x64_sys_clock_gettime+0x165/0x240 kernel/time/posix-timers.c:1082 __ia32_sys_clock_settime+0x260/0x260 kernel/time/posix-timers.c:1410 __do_sys_socketpair net/socket.c:1637 [inline] __se_sys_socketpair net/socket.c:1634 [inline] __x64_sys_socketpair+0x93/0xf0 net/socket.c:1634 __trace_hardirqs_on_caller kernel/locking/lockdep.c:3657 [inline] lockdep_hardirqs_on+0x463/0x620 kernel/locking/lockdep.c:3702 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 INFO: task syz-executor.0:15369 blocked for more than 143 seconds. Not tainted 5.7.0-rc5-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29320 15369 7095 0x00004004 Call Trace: context_switch kernel/sched/core.c:3367 [inline] __schedule+0x937/0x1ff0 kernel/sched/core.c:4083 rwsem_down_write_slowpath+0x90a/0xf90 kernel/locking/rwsem.c:1216 __sched_text_start+0x8/0x8 schedule+0xd0/0x2a0 kernel/sched/core.c:4158 rwsem_down_write_slowpath+0x706/0xf90 kernel/locking/rwsem.c:1235 rwsem_mark_wake+0x8d0/0x8d0 include/linux/compiler.h:199 lock_acquire+0x1f2/0x8f0 kernel/locking/lockdep.c:4934 register_netdevice_notifier+0x1e/0x270 net/core/dev.c:1729 lock_release+0x800/0x800 kernel/locking/lockdep.c:4689 find_held_lock+0x2d/0x110 kernel/locking/lockdep.c:4458 __down_write kernel/locking/rwsem.c:1389 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1532 atomic64_try_cmpxchg include/asm-generic/atomic-instrumented.h:1504 [inline] atomic_long_try_cmpxchg_acquire include/asm-generic/atomic-long.h:442 [inline] __down_write kernel/locking/rwsem.c:1387 [inline] down_write+0xb2/0x150 kernel/locking/rwsem.c:1532 __down_write kernel/locking/rwsem.c:1389 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1532 __down_timeout+0x2d0/0x2d0 lockdep_init_map_waits+0x26a/0x890 kernel/locking/lockdep.c:4138 register_netdevice_notifier+0x1e/0x270 net/core/dev.c:1729 bcm_init+0x1a3/0x210 net/can/bcm.c:1451 canbcm_pernet_init+0x90/0x90 net/can/bcm.c:1677 can_create+0x27c/0x500 net/can/af_can.c:168 __sock_create+0x3cb/0x730 net/socket.c:1433 sock_create net/socket.c:1484 [inline] __sys_socketpair+0x1be/0x560 net/socket.c:1584 __ia32_sys_socket+0xb0/0xb0 net/socket.c:1533 __do_sys_clock_gettime kernel/time/posix-timers.c:1094 [inline] __se_sys_clock_gettime kernel/time/posix-timers.c:1082 [inline] __x64_sys_clock_gettime+0x165/0x240 kernel/time/posix-timers.c:1082 __ia32_sys_clock_settime+0x260/0x260 kernel/time/posix-timers.c:1410 __do_sys_socketpair net/socket.c:1637 [inline] __se_sys_socketpair net/socket.c:1634 [inline] __x64_sys_socketpair+0x93/0xf0 net/socket.c:1634 __trace_hardirqs_on_caller kernel/locking/lockdep.c:3657 [inline] lockdep_hardirqs_on+0x463/0x620 kernel/locking/lockdep.c:3702 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Showing all locks held in the system: 4 locks held by kworker/u4:3/96: 3 locks held by kworker/u4:5/664: 1 lock held by khungtaskd/1140: #0: ffffffff899bea80 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5754 1 lock held by in:imklog/6770: #0: ffff888092cc5b70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 3 locks held by kworker/u4:0/22952: #0: ffff8880a9771938 ((wq_completion)netns){+.+.}-{0:0}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880a9771938 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880a9771938 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880a9771938 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880a9771938 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8880a9771938 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8880a9771938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 kernel/workqueue.c:2239 #1: ffffc90002197dc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 kernel/workqueue.c:2243 #2: ffffffff8a57a930 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 net/core/net_namespace.c:565 1 lock held by syz-executor.0/15339: #0: ffffffff8a57a930 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x270 net/core/dev.c:1729 1 lock held by syz-executor.0/15369: #0: ffffffff8a57a930 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x270 net/core/dev.c:1729 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1140 Comm: khungtaskd Not tainted 5.7.0-rc5-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+0x188/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 lapic_can_unplug_cpu.cold+0x3b/0x3b nmi_trigger_cpumask_backtrace+0x231/0x27e lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xa8c/0x1010 kernel/hung_task.c:289 reset_hung_task_detector+0x30/0x30 kernel/hung_task.c:243 kthread+0x388/0x470 kernel/kthread.c:268 kthread_mod_delayed_work+0x1a0/0x1a0 kernel/kthread.c:1090 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 664 Comm: kworker/u4:5 Not tainted 5.7.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:rcu_is_watching+0x16/0x20 kernel/rcu/tree.c:930 Code: 00 48 8b 04 24 eb 90 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 65 ff 05 81 e2 a1 7e e8 44 ff ff ff 83 f0 01 65 ff 0d 72 e2 a1 7e <74> 01 c3 e8 26 3a a0 ff c3 90 55 48 89 f5 be 04 00 00 00 53 89 fb RSP: 0018:ffffc90003017cc8 EFLAGS: 00000286 RAX: 0000000000000001 RBX: ffff88805bd7a500 RCX: ffffffff81603bdf RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880ae738818 RBP: ffff88806b91cc00 R08: ffff8880a78303c0 R09: ffffed1015ce7104 R10: ffff8880ae73881b R11: ffffed1015ce7103 R12: 0000000000000000 R13: 00000000000001e8 R14: dffffc0000000000 R15: ffff88805dd44f40 FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f288a18c000 CR3: 00000000a142e000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: rcu_read_lock include/linux/rcupdate.h:602 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:407 [inline] batadv_nc_worker+0x4c3/0x760 net/batman-adv/network-coding.c:718 process_one_work+0x965/0x16a0 kernel/workqueue.c:2268 lock_release+0x800/0x800 kernel/locking/lockdep.c:4689 pwq_dec_nr_in_flight+0x310/0x310 kernel/workqueue.c:1198 rwlock_bug.part.0+0x90/0x90 include/linux/sched.h:1329 worker_thread+0x96/0xe20 kernel/workqueue.c:2414 process_one_work+0x16a0/0x16a0 kernel/workqueue.c:2273 kthread+0x388/0x470 kernel/kthread.c:268 kthread_mod_delayed_work+0x1a0/0x1a0 kernel/kthread.c:1090 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351