INFO: task syz-executor.0:19392 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.0 D28392 19392 7048 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.0:19425 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.0 D28392 19425 7048 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: 1 lock held by khungtaskd/1125: #0: ffffffff899bea80 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5754 2 locks held by in:imklog/6724: 2 locks held by agetty/6757: #0: ffff8880a6857098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc90000ea42e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x220/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by agetty/6759: #0: ffff8880a6084098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc90000f902e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x220/0x1b30 drivers/tty/n_tty.c:2156 3 locks held by kworker/u4:3/5427: #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: ffffc900063a7dc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 kernel/workqueue.c:2243 #2: ffffffff8a577370 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 net/core/net_namespace.c:565 1 lock held by syz-executor.0/19392: #0: ffffffff8a577370 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x270 net/core/dev.c:1729 1 lock held by syz-executor.0/19425: #0: ffffffff8a577370 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x270 net/core/dev.c:1729 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1125 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 6725 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:match_held_lock+0x225/0x500 kernel/locking/lockdep.c:4445 Code: ea 03 80 3c 02 00 0f 85 db 02 00 00 48 8b 2c ed e0 c8 2d 8c 49 bd 00 00 00 00 00 fc ff df 48 85 ed 75 3c 31 c0 48 83 c4 08 5b <5d> 41 5c 41 5d 41 5e c3 48 83 c4 08 b8 01 00 00 00 5b 5d 41 5c 41 RSP: 0018:ffffc90009897458 EFLAGS: 00000096 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff899be9c0 RDI: ffff88809518abaa RBP: ffff88809518a2c0 R08: ffff88809518a2c0 R09: ffffed1015ce7104 R10: ffff8880ae73881b R11: ffffed1015ce7103 R12: ffffed1012a31570 R13: ffff88809518ab88 R14: ffff88809518ab80 R15: ffffffff899be9c0 FS: 00007f32be0ee700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f03bdaff000 CR3: 0000000099e77000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_is_held kernel/locking/lockdep.c:4708 [inline] lock_is_held_type+0x1a6/0x350 kernel/locking/lockdep.c:4971 lock_is_held include/linux/lockdep.h:406 [inline] rcu_read_lock_sched_held+0x9c/0xd0 kernel/rcu/update.c:121 rcu_read_lock_any_held.part.0+0x50/0x50 arch/x86/include/asm/paravirt.h:754 mark_held_locks+0x9f/0xe0 kernel/locking/lockdep.c:3628 lookup_bh_lru fs/buffer.c:1314 [inline] __find_get_block+0x23c/0xe90 fs/buffer.c:1326 trace_block_touch_buffer include/trace/events/block.h:45 [inline] touch_buffer fs/buffer.c:62 [inline] __find_get_block+0xb95/0xe90 fs/buffer.c:1334 __getblk_gfp+0x33/0xae0 fs/buffer.c:1352 ext4_get_group_desc+0x298/0x500 fs/ext4/balloc.c:302 sb_getblk include/linux/buffer_head.h:333 [inline] __ext4_get_inode_loc+0x3e4/0x12b0 fs/ext4/inode.c:4279 ext4_da_get_block_prep+0x1120/0x1120 include/linux/buffer_head.h:353 ext4_dirty_inode+0xe7/0x120 fs/ext4/inode.c:5827 ext4_reserve_inode_write+0xc6/0x230 fs/ext4/inode.c:5622 ext4_dirty_inode+0xe7/0x120 fs/ext4/inode.c:5827 ext4_mark_inode_dirty+0x174/0x900 fs/ext4/inode.c:5788 ext4_expand_extra_isize+0x5a0/0x5a0 fs/ext4/inode.c:5733 ___might_sleep+0x15a/0x2b0 kernel/sched/core.c:6768 ext4_journal_check_start+0x1ae/0x290 fs/ext4/ext4_jbd2.c:86 __ext4_journal_start_sb+0x14e/0x4d0 fs/ext4/ext4_jbd2.c:105 __ext4_journal_start fs/ext4/ext4_jbd2.h:325 [inline] ext4_dirty_inode+0xbc/0x120 fs/ext4/inode.c:5823 ext4_dirty_inode+0xe7/0x120 fs/ext4/inode.c:5827 ext4_setattr+0x1f00/0x1f00 fs/ext4/inode.c:5365 __mark_inode_dirty+0x65e/0x1350 fs/fs-writeback.c:2258 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 perf_trace_lock_acquire+0xf5/0x530 include/trace/events/lock.h:13 ext4_buffered_write_iter+0x450/0x450 include/linux/backing-dev.h:169 mark_held_locks+0xe0/0xe0 kernel/locking/lockdep.c:3620 perf_trace_lock+0x4c0/0x4c0 include/linux/compiler.h:199 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: 0033:0x7f32c0b321cd 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:00007f32be0ed590 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f32b40288a0 RCX: 00007f32c0b321cd RDX: 0000000000000476 RSI: 00007f32b40288a0 RDI: 000000000000000a RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f32b4028620 R13: 00007f32be0ed5b0 R14: 000055b456ec97c0 R15: 0000000000000476