INFO: task kworker/u4:15:3937 blocked for more than 143 seconds. Not tainted 6.1.106-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:15 state:D stack:20344 pid:3937 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:0) Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189 f2fs_down_write fs/f2fs/f2fs.h:2176 [inline] f2fs_balance_fs+0x4fb/0x6c0 fs/f2fs/segment.c:428 f2fs_write_inode+0x4c3/0x540 fs/f2fs/inode.c:739 write_inode fs/fs-writeback.c:1460 [inline] __writeback_single_inode+0x67d/0x11e0 fs/fs-writeback.c:1677 writeback_sb_inodes+0xc2b/0x1b20 fs/fs-writeback.c:1903 __writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:1974 wb_writeback+0x4b1/0xe10 fs/fs-writeback.c:2079 wb_check_background_flush fs/fs-writeback.c:2145 [inline] wb_do_writeback fs/fs-writeback.c:2233 [inline] wb_workfn+0xc9e/0x1020 fs/fs-writeback.c:2260 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32b190 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d32b990 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516 1 lock held by khungtaskd/28: #0: ffffffff8d32afc0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32afc0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32afc0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494 2 locks held by kworker/u4:2/41: #0: ffff888012879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90000b27d20 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 2 locks held by getty/3388: #0: ffff8880283f7098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2198 4 locks held by kworker/u4:15/3937: #0: ffff88814165b138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90004807d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffff888054b3e0e0 (&type->s_umount_key#68){++++}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415 #3: ffff88805ce31140 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2176 [inline] #3: ffff88805ce31140 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x4fb/0x6c0 fs/f2fs/segment.c:428 2 locks held by kworker/u4:11/10516: #0: ffff888012879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000341fd20 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 2 locks held by kworker/1:12/13506: 5 locks held by syz.0.2410/13819: 1 lock held by syz.3.3008/15942: #0: ffffffff8d3305b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #0: ffffffff8d3305b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 1 lock held by syz.2.3014/15961: #0: ffff88805f596810 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #0: ffff88805f596810 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release net/socket.c:653 [inline] #0: ffff88805f596810 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: sock_close+0x98/0x230 net/socket.c:1400 2 locks held by syz.2.3014/15963: #0: ffffffff8d1e82a8 (sched_core_mutex){+.+.}-{3:3}, at: sched_core_get+0x49/0x1d0 kernel/sched/core.c:398 #1: ffffffff8d3305b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #1: ffffffff8d3305b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4f0/0x930 kernel/rcu/tree_exp.h:962 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.106-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1b0/0x3f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf88/0xfd0 kernel/hung_task.c:377 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 15951 Comm: syz.4.3012 Not tainted 6.1.106-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:trace_hardirqs_on+0x2f/0x40 kernel/trace/trace_preemptirq.c:49 Code: 71 7e 85 c0 74 24 65 8b 05 a6 08 71 7e a9 00 00 f0 00 75 0b 48 8b 3c 24 31 f6 e8 1c 00 00 00 65 c7 05 79 ce 71 7e 00 00 00 00 0c d3 d8 ff 48 8b 3c 24 e9 b3 04 14 09 0f 1f 00 55 41 57 41 56 RSP: 0018:ffffc9000df1f4b8 EFLAGS: 00000046 RAX: 0000000080000000 RBX: 1ffff92001be3e9c RCX: 0000000000000001 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffffff81542104 RBP: ffffc9000df1f578 R08: dffffc0000000000 R09: fffff5200370140a R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff92001be3ea0 R14: ffffc9000df1f500 R15: 0000000000000201 FS: 00007f6a61a896c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555556dcb5c8 CR3: 000000005c4c0000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __local_bh_enable_ip+0x164/0x1f0 kernel/softirq.c:401 spin_unlock_bh include/linux/spinlock.h:396 [inline] htable_selective_cleanup+0x25f/0x310 net/netfilter/xt_hashlimit.c:374 htable_put+0x1ed/0x240 net/netfilter/xt_hashlimit.c:430 cleanup_match net/ipv6/netfilter/ip6_tables.c:479 [inline] cleanup_entry+0x207/0x4d0 net/ipv6/netfilter/ip6_tables.c:663 translate_table+0x212e/0x2320 net/ipv6/netfilter/ip6_tables.c:746 do_replace net/ipv6/netfilter/ip6_tables.c:1156 [inline] do_ip6t_set_ctl+0xe30/0x1250 net/ipv6/netfilter/ip6_tables.c:1646 nf_setsockopt+0x28a/0x2b0 net/netfilter/nf_sockopt.c:101 rawv6_setsockopt+0x323/0x750 net/ipv6/raw.c:1052 __sys_setsockopt+0x57e/0xa00 net/socket.c:2283 __do_sys_setsockopt net/socket.c:2294 [inline] __se_sys_setsockopt net/socket.c:2291 [inline] __x64_sys_setsockopt+0xb1/0xc0 net/socket.c:2291 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f6a60d79e79 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6a61a89038 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007f6a60f15f80 RCX: 00007f6a60d79e79 RDX: 0000000000000040 RSI: 0000000000000029 RDI: 0000000000000003 RBP: 00007f6a60de793e R08: 0000000000000588 R09: 0000000000000000 R10: 00000000200014c0 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f6a60f15f80 R15: 00007ffcb2d22f78