INFO: task syz-executor.2:24032 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 D26144 24032 7301 0x80004006 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 unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1776 lock_release+0x800/0x800 kernel/locking/lockdep.c:4689 __sock_release+0x280/0x280 net/socket.c:605 __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 unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1776 __sock_release+0x280/0x280 net/socket.c:605 raw_release+0x53/0x730 net/can/raw.c:354 fcntl_setlk+0xcc0/0xcc0 fs/locks.c:2542 __sock_release+0x280/0x280 net/socket.c:605 __sock_release+0xcd/0x280 net/socket.c:605 sock_close+0x18/0x20 net/socket.c:1283 __fput+0x33e/0x880 fs/file_table.c:280 task_work_run+0xf4/0x1b0 kernel/task_work.c:123 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xb34/0x2dd0 kernel/exit.c:796 find_held_lock+0x2d/0x110 kernel/locking/lockdep.c:4458 mm_update_next_owner+0x7a0/0x7a0 kernel/exit.c:375 lock_downgrade+0x840/0x840 kernel/locking/lockdep.c:4579 do_group_exit+0x125/0x340 kernel/exit.c:894 get_signal+0x47b/0x24e0 kernel/signal.c:2739 find_held_lock+0x2d/0x110 kernel/locking/lockdep.c:4458 do_signal+0x81/0x2240 arch/x86/kernel/signal.c:784 lock_downgrade+0x840/0x840 kernel/locking/lockdep.c:4579 rcu_read_lock_any_held.part.0+0x50/0x50 arch/x86/include/asm/paravirt.h:754 get_sigframe.isra.0+0x730/0x730 arch/x86/kernel/signal.c:268 rcu_read_unlock_sched include/linux/rcupdate.h:732 [inline] __fd_install+0x1e6/0x600 fs/file.c:613 __sys_socket+0x16d/0x200 net/socket.c:438 move_addr_to_kernel+0x70/0x70 net/socket.c:195 exit_to_usermode_loop+0x26c/0x360 arch/x86/entry/common.c:161 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x6b1/0x7d0 arch/x86/entry/common.c:305 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Showing all locks held in the system: 3 locks held by kworker/u4:0/7: #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: ffffc90000cdfdc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 kernel/workqueue.c:2243 #2: ffffffff8a576f70 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 net/core/net_namespace.c:565 1 lock held by khungtaskd/1131: #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/6703: #0: ffff8880a29d5930 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 2 locks held by syz-executor.5/9725: #0: ffff88809106e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffff88809106e130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock+0x1e/0x80 drivers/tty/tty_io.c:888 2 locks held by syz-executor.5/9788: #0: ffff8880a320d098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffff8880a320d130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock+0x1e/0x80 drivers/tty/tty_io.c:888 2 locks held by syz-executor.5/9883: #0: ffff888095121098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffff888095121130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock+0x1e/0x80 drivers/tty/tty_io.c:888 2 locks held by syz-executor.5/9943: #0: ffff888093677098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffff888093677130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock+0x1e/0x80 drivers/tty/tty_io.c:888 2 locks held by syz-executor.5/9988: #0: ffff8880a8752098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffff8880a8752130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock+0x1e/0x80 drivers/tty/tty_io.c:888 2 locks held by syz-executor.5/10293: #0: ffff888091e78098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffff888091e78130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock+0x1e/0x80 drivers/tty/tty_io.c:888 2 locks held by syz-executor.5/10567: #0: ffff888046c2f098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffff888046c2f130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock+0x1e/0x80 drivers/tty/tty_io.c:888 2 locks held by syz-executor.5/27626: #0: ffff88804bd04098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffff88804bd04130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock+0x1e/0x80 drivers/tty/tty_io.c:888 2 locks held by syz-executor.5/27632: #0: ffff888021008098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffff888021008130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock+0x1e/0x80 drivers/tty/tty_io.c:888 2 locks held by syz-executor.5/27747: #0: ffff88809e59d098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffff88809e59d130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock+0x1e/0x80 drivers/tty/tty_io.c:888 2 locks held by syz-executor.5/27774: #0: ffff88809468e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffff88809468e130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock+0x1e/0x80 drivers/tty/tty_io.c:888 2 locks held by syz-executor.5/28717: #0: ffff888046a3f098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffff888046a3f130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock+0x1e/0x80 drivers/tty/tty_io.c:888 2 locks held by syz-executor.5/28857: #0: ffff88805ab41098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffff88805ab41130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock+0x1e/0x80 drivers/tty/tty_io.c:888 1 lock held by syz-executor.5/17274: #0: ffff8880920c3468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock_nested fs/pipe.c:65 [inline] #0: ffff8880920c3468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock+0x5a/0x70 fs/pipe.c:73 2 locks held by syz-executor.2/24032: #0: ffff8881c7ec0c90 (&sb->s_type->i_mutex_key#14){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:797 [inline] #0: ffff8881c7ec0c90 (&sb->s_type->i_mutex_key#14){+.+.}-{3:3}, at: __sock_release+0x86/0x280 net/socket.c:604 #1: ffffffff8a576f70 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1776 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1131 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: 6706 Comm: rs:main Q:Reg Not tainted 5.7.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_acquire+0x1b91/0x4c50 kernel/locking/lockdep.c:4325 Code: eb be 08 00 00 00 49 8d 45 3f 4d 85 ed 49 0f 49 c5 48 c1 f8 06 48 8d 3c c5 60 79 2e 8c e8 97 97 57 00 4c 0f a3 2d ff 39 d5 0a <0f> 82 57 ee ff ff e8 94 70 3a 02 85 c0 0f 84 e9 fd ff ff 48 c7 c0 RSP: 0018:ffffc9000407f260 EFLAGS: 00000047 RAX: 0000000000000001 RBX: 000000000000001d RCX: ffffffff81593f59 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8c2e7960 RBP: ffff88809a1a8ca8 R08: 0000000000000001 R09: fffffbfff185cf2d R10: ffffffff8c2e7967 R11: fffffbfff185cf2c R12: ffff88809a1a8340 R13: 000000000000001d R14: ffff88809a1a8cca R15: 0000000000000000 FS: 00007f93193e3700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9310027000 CR3: 00000000a3561000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: find_held_lock+0x2d/0x110 kernel/locking/lockdep.c:4458 __free_one_page+0x200/0x1050 mm/page_alloc.c:986 mark_held_locks+0xe0/0xe0 kernel/locking/lockdep.c:3620 lock_release+0x800/0x800 kernel/locking/lockdep.c:4689 lock_acquire+0x1f2/0x8f0 kernel/locking/lockdep.c:4934 spin_lock include/linux/spinlock.h:353 [inline] free_one_page+0x2c/0x1c0 mm/page_alloc.c:1383 lock_release+0x800/0x800 kernel/locking/lockdep.c:4689 __free_pages_ok+0x457/0xe90 mm/page_alloc.c:1478 trace_hardirqs_off+0x50/0x220 kernel/trace/trace_preemptirq.c:45 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] _raw_spin_unlock_irqrestore+0x9b/0xe0 kernel/locking/spinlock.c:191 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:353 [inline] free_one_page+0x2c/0x1c0 mm/page_alloc.c:1383 spin_lock include/linux/spinlock.h:353 [inline] free_one_page+0x2c/0x1c0 mm/page_alloc.c:1383 __free_pages_ok+0x457/0xe90 mm/page_alloc.c:1478 slab_destroy+0x14/0x40 mm/slab.c:1620 slabs_destroy+0x6a/0x90 mm/slab.c:1636 cache_flusharray mm/slab.c:3413 [inline] ___cache_free+0x29f/0x3a0 mm/slab.c:3457 mark_held_locks+0x9f/0xe0 kernel/locking/lockdep.c:3628 qlink_free mm/kasan/quarantine.c:148 [inline] qlist_free_all+0x79/0x140 mm/kasan/quarantine.c:167 quarantine_reduce+0x159/0x190 mm/kasan/quarantine.c:260 __kasan_kmalloc.constprop.0+0x97/0xd0 mm/kasan/common.c:476 slab_post_alloc_hook mm/slab.h:586 [inline] slab_alloc mm/slab.c:3320 [inline] kmem_cache_alloc+0x11b/0x740 mm/slab.c:3484 mem_cgroup_hierarchy_write+0x200/0x200 mm/memcontrol.c:3272 kmem_cache_zalloc include/linux/slab.h:659 [inline] alloc_buffer_head+0x20/0x110 fs/buffer.c:3347 alloc_page_buffers+0x167/0x590 fs/buffer.c:865 create_empty_buffers+0x2c/0x8c0 fs/buffer.c:1563 ext4_block_write_begin+0x10ab/0x1430 fs/ext4/inode.c:1034 other_inode_match+0xab0/0xab0 fs/ext4/inode.c:4890 ext4_dax_writepages+0xba0/0xba0 include/linux/percpu-rwsem.h:118 ext4_journal_check_start+0x1ae/0x290 fs/ext4/ext4_jbd2.c:86 ext4_da_write_begin+0x56e/0xbc0 fs/ext4/inode.c:2995 ext4_write_begin+0xda0/0xda0 include/linux/compiler.h:199 copyin+0x140/0x140 lib/iov_iter.c:149 generic_perform_write+0x20a/0x4e0 mm/filemap.c:3302 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: 0033:0x7f931be271cd 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:00007f93193e2590 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f9310026e40 RCX: 00007f931be271cd RDX: 0000000000000476 RSI: 00007f9310026e40 RDI: 0000000000000008 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f9310026bc0 R13: 00007f93193e25b0 R14: 000055d6714ef440 R15: 0000000000000476