INFO: task syz-executor:5773 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21640 pid:5773 ppid:1 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5380 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699 schedule+0xbd/0x170 kernel/sched/core.c:6773 wb_wait_for_completion+0x166/0x290 fs/fs-writeback.c:192 sync_inodes_sb+0x1bc/0x9e0 fs/fs-writeback.c:2772 sync_filesystem+0x171/0x220 fs/sync.c:64 generic_shutdown_super+0x6f/0x2b0 fs/super.c:666 kill_block_super+0x44/0x90 fs/super.c:1660 deactivate_locked_super+0x97/0x100 fs/super.c:481 cleanup_mnt+0x429/0x4c0 fs/namespace.c:1259 task_work_run+0x1ce/0x250 kernel/task_work.c:239 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x90b/0x23c0 kernel/exit.c:883 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024 __do_sys_exit_group kernel/exit.c:1035 [inline] __se_sys_exit_group kernel/exit.c:1033 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1033 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f96c0b8f749 RSP: 002b:00007ffe8a519a78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f96c0c13ddd RCX: 00007f96c0b8f749 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 000000000000000c R08: 00007ffe8a517816 R09: 00007ffe8a51ad30 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe8a51ad30 R13: 00007f96c0c13d7d R14: 000055558d80d4a8 R15: 00007ffe8a51be00 Showing all locks held in the system: 2 locks held by kworker/u4:1/12: 1 lock held by khungtaskd/29: #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by kworker/u4:3/49: #0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc90000ba7d00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc90000ba7d00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 2 locks held by kworker/u4:9/2954: #0: ffff88801a27ed38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff88801a27ed38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc9000bdf7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc9000bdf7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 3 locks held by kworker/0:3/5153: #0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc90003377d00 (trans_destroy_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc90003377d00 (trans_destroy_work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffffffff8cd358f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline] #2: ffffffff8cd358f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x830 kernel/rcu/tree_exp.h:1004 2 locks held by getty/5528: #0: ffff88802cbeb0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217 2 locks held by syz-executor/5773: #0: ffff88805ba2c0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88805ba2c0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88805ba2c0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffff8881423d27d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:364 [inline] #1: ffff8881423d27d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x1a0/0x9e0 fs/fs-writeback.c:2770 2 locks held by kworker/0:6/5832: #0: ffff888017872538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017872538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc900047dfd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc900047dfd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 2 locks held by syz-executor/6360: #0: ffff88801abfa0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88801abfa0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88801abfa0e0 (&type->s_umount_key#59){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffff88814272c7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:364 [inline] #1: ffff88814272c7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x1a0/0x9e0 fs/fs-writeback.c:2770 3 locks held by syz.8.427/8373: #0: ffff88804cbc2020 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #0: ffff88804cbc2020 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline] #0: ffff88804cbc2020 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x9b/0x230 net/socket.c:1421 #1: ffffffff8e0182b0 ((netlink_chain).rwsem){++++}-{3:3}, at: blocking_notifier_call_chain+0x54/0x90 kernel/notifier.c:387 #2: ffff88802cddfab8 (&nft_net->commit_mutex){+.+.}-{3:3}, at: nft_rcv_nl_event+0x115/0x590 net/netfilter/nf_tables_api.c:11383 3 locks held by syz.4.425/8376: #0: ffff88804cbc0820 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #0: ffff88804cbc0820 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline] #0: ffff88804cbc0820 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x9b/0x230 net/socket.c:1421 #1: ffffffff8e0182b0 ((netlink_chain).rwsem){++++}-{3:3}, at: blocking_notifier_call_chain+0x54/0x90 kernel/notifier.c:387 #2: ffff88802c7e26b8 (&nft_net->commit_mutex){+.+.}-{3:3}, at: nft_rcv_nl_event+0x115/0x590 net/netfilter/nf_tables_api.c:11383 1 lock held by dhcpcd-run-hook/8396: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf41/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 6709 Comm: segctord Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:__kasan_check_write+0x0/0x20 mm/kasan/shadow.c:37 Code: e8 f5 2a 7f 08 31 ed eb d4 cc f3 0f 1e fa 89 f6 48 8b 0c 24 31 d2 e9 df ea ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 0f 1e fa 89 f6 48 8b 0c 24 ba 01 00 00 00 e9 bc ea ff ff 66 2e RSP: 0018:ffffc900036d7c28 EFLAGS: 00000246 RAX: 1ffff1100b761e47 RBX: ffff88805bb0f230 RCX: ffffffff81666a7f RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88805bb0f230 RBP: dffffc0000000000 R08: ffff88805bb0f23f R09: 1ffff1100b761e47 R10: dffffc0000000000 R11: ffffed100b761e48 R12: ffff88805bb0f238 R13: ffff88805bb0f298 R14: ffff88805bb0f238 R15: 1ffff1100b761e47 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1c1d5657b8 CR3: 000000000cb30000 CR4: 00000000003506e0 Call Trace: instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_long_fetch_add_release include/linux/atomic/atomic-instrumented.h:3362 [inline] __up_write kernel/locking/rwsem.c:1374 [inline] up_write+0x1a9/0x410 kernel/locking/rwsem.c:1626 nilfs_transaction_unlock fs/nilfs2/segment.c:381 [inline] nilfs_segctor_thread_construct fs/nilfs2/segment.c:2572 [inline] nilfs_segctor_thread+0x8f3/0x1000 fs/nilfs2/segment.c:2646 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293