INFO: task syz-executor.4:20932 blocked for more than 143 seconds. Not tainted 5.7.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D27064 20932 7407 0x00004004 Call Trace: context_switch kernel/sched/core.c:3367 [inline] __schedule+0x937/0x1ff0 kernel/sched/core.c:4083 __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 arch_local_irq_restore arch/x86/include/asm/paravirt.h:759 [inline] lock_acquire+0x267/0x8f0 kernel/locking/lockdep.c:4937 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 can_create+0x1e1/0x500 net/can/af_can.c:159 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.4:20981 blocked for more than 143 seconds. Not tainted 5.7.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D29600 20981 7407 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: 3 locks held by kworker/u4:2/24: #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: ffffc90000e17dc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 kernel/workqueue.c:2243 #2: ffffffff8a57aaf0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 net/core/net_namespace.c:565 1 lock held by khungtaskd/1144: #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/6721: #0: ffff8880a20eddf0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 1 lock held by syz-executor.4/20932: #0: ffffffff8a57aaf0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x270 net/core/dev.c:1729 1 lock held by syz-executor.4/20981: #0: ffffffff8a57aaf0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x270 net/core/dev.c:1729 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1144 Comm: khungtaskd Not tainted 5.7.0-rc6-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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 6722 Comm: rs:main Q:Reg Not tainted 5.7.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__sanitizer_cov_trace_pc+0x16/0x50 kernel/kcov.c:183 Code: f0 13 00 00 c3 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 65 48 8b 04 25 00 1f 02 00 65 8b 15 98 e9 8e 7e 81 e2 00 01 1f 00 <48> 8b 34 24 75 2b 8b 90 d8 13 00 00 83 fa 02 75 20 48 8b 88 e0 13 RSP: 0018:ffffc90004347920 EFLAGS: 00000246 RAX: ffff888094590080 RBX: ffff88808a9ab638 RCX: ffffffff81c771d0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 0000000000000007 R08: ffff888094590080 R09: fffffbfff1513311 R10: ffffffff8a899887 R11: fffffbfff1513310 R12: 0000000000000001 R13: ffff8882148ee000 R14: 0000000000000001 R15: 00000000000930c3 FS: 00007f262b8df700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f88b1cef010 CR3: 00000000a1d85000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __preempt_count_add arch/x86/include/asm/preempt.h:79 [inline] rcu_read_lock_sched_notrace include/linux/rcupdate.h:717 [inline] trace_writeback_mark_inode_dirty include/trace/events/writeback.h:127 [inline] __mark_inode_dirty+0x78c/0x1350 fs/fs-writeback.c:2248 unlock_page+0x175/0x2a0 mm/filemap.c:1294 mark_inode_dirty include/linux/fs.h:2189 [inline] generic_write_end+0x2f4/0x3d0 fs/buffer.c:2204 ext4_da_write_end+0x217/0xbd0 fs/ext4/inode.c:3090 generic_perform_write+0x2c0/0x4e0 mm/filemap.c:3313 update_time+0xc0/0xc0 fs/inode.c:1693 trace_event_raw_event_file_check_and_advance_wb_err+0x4a0/0x4a0 include/trace/events/filemap.h:82 ext4_buffered_write_iter+0x1f7/0x450 fs/ext4/file.c:270 ext4_file_write_iter+0x1ec/0x13f0 fs/ext4/file.c:642 aa_path_link+0x300/0x300 security/apparmor/file.c:493 ext4_buffered_write_iter+0x450/0x450 include/linux/backing-dev.h:169 mark_held_locks+0xe0/0xe0 kernel/locking/lockdep.c:3620 call_write_iter include/linux/fs.h:1907 [inline] new_sync_write+0x4a2/0x700 fs/read_write.c:484 new_sync_read+0x7a0/0x7a0 fs/read_write.c:415 lock_is_held include/linux/lockdep.h:406 [inline] rcu_read_lock_any_held+0xcd/0xf0 kernel/rcu/update.c:344 rcu_read_lock_bh_held+0xb0/0xb0 kernel/rcu/update.c:333 __vfs_write+0xc9/0x100 fs/read_write.c:497 vfs_write+0x268/0x5d0 fs/read_write.c:559 ksys_write+0x12d/0x250 fs/read_write.c:612 __ia32_sys_read+0xb0/0xb0 fs/read_write.c:596 trace_hardirqs_off_caller+0x55/0x230 kernel/trace/trace_preemptirq.c:73 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x7f262e3231cd Code: c2 20 00 00 75 10 b8 01 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ae fc ff ff 48 89 04 24 b8 01 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 f7 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007f262b8de590 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f2620002dc0 RCX: 00007f262e3231cd RDX: 0000000000000453 RSI: 00007f2620002dc0 RDI: 0000000000000006 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f2620002b20 R13: 00007f262b8de5b0 R14: 000055c40a025360 R15: 0000000000000453