INFO: task syz-executor.2:28946 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.2 D28752 28946 7209 0x00000004 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 pcpu_alloc+0xfed/0x13b0 mm/percpu.c:1703 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 __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 pcpu_alloc+0x128/0x13b0 mm/percpu.c:1740 register_netdevice_notifier+0x1e/0x270 net/core/dev.c:1729 raw_init+0x296/0x340 net/can/raw.c:339 raw_sock_no_ioctlcmd+0x10/0x10 net/can/raw.c:843 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_socket+0xef/0x200 net/socket.c:1526 move_addr_to_kernel+0x70/0x70 net/socket.c:195 __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 trace_hardirqs_off_caller+0x55/0x230 kernel/trace/trace_preemptirq.c:73 __do_sys_socket net/socket.c:1535 [inline] __se_sys_socket net/socket.c:1533 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1533 __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.2:28966 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.2 D24304 28966 7209 0x00000004 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 pcpu_alloc+0xfed/0x13b0 mm/percpu.c:1703 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 __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 pcpu_alloc+0x128/0x13b0 mm/percpu.c:1740 register_netdevice_notifier+0x1e/0x270 net/core/dev.c:1729 raw_init+0x296/0x340 net/can/raw.c:339 raw_sock_no_ioctlcmd+0x10/0x10 net/can/raw.c:843 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_socket+0xef/0x200 net/socket.c:1526 move_addr_to_kernel+0x70/0x70 net/socket.c:195 __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 trace_hardirqs_off_caller+0x55/0x230 kernel/trace/trace_preemptirq.c:73 __do_sys_socket net/socket.c:1535 [inline] __se_sys_socket net/socket.c:1533 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1533 __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/u4:6/444: 1 lock held by khungtaskd/1142: #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/6719: #0: ffff88809a53d3f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 3 locks held by kworker/u4:7/9217: 4 locks held by kworker/u4:10/27534: 1 lock held by syz-executor.2/28946: #0: ffffffff8a5772f0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x270 net/core/dev.c:1729 1 lock held by syz-executor.2/28966: #0: ffffffff8a5772f0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x270 net/core/dev.c:1729 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1142 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: 27534 Comm: kworker/u4:10 Not tainted 5.7.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: krdsd rds_tcp_accept_worker RIP: 0010:trace_hardirqs_on+0x67/0x220 kernel/trace/trace_preemptirq.c:26 Code: db 74 27 e8 7b 7f fa ff 65 c7 05 70 72 8a 7e 00 00 00 00 e8 6b 7f fa ff 48 8b 7c 24 28 5b 5d 41 5c 41 5d 41 5e e9 f9 03 e1 ff 54 7f fa ff 4c 8b 6c 24 28 0f 1f 44 00 00 e8 45 7f fa ff eb c3 RSP: 0018:ffffc900045e7b28 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8178b4fc RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005 RBP: ffffffff86a651c3 R08: ffff888046f96500 R09: fffffbfff1512b31 R10: ffffffff8a895987 R11: fffffbfff1512b30 R12: ffff888046f96500 R13: 1ffff920008bcf70 R14: ffff8880551d1a98 R15: ffff8880551d1ac0 FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5ff33d2000 CR3: 000000009206a000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: sock_graft include/net/sock.h:1883 [inline] inet_accept+0x2c3/0x7c0 net/ipv4/af_inet.c:746 __local_bh_enable_ip+0x159/0x270 kernel/softirq.c:194 sock_graft include/net/sock.h:1883 [inline] inet_accept+0x2c3/0x7c0 net/ipv4/af_inet.c:746 ipv4_mib_exit_net+0x1c0/0x1c0 net/ipv4/af_inet.c:1790 rds_tcp_accept_one+0x1c2/0xb70 net/rds/tcp_listen.c:149 rds_tcp_set_linger+0xb0/0xb0 net/rds/tcp_listen.c:123 lock_is_held include/linux/lockdep.h:406 [inline] rcu_read_lock_sched_held+0x9c/0xd0 kernel/rcu/update.c:121 rds_tcp_accept_worker+0x50/0x80 net/rds/tcp.c:525 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