INFO: task syz.3.153:4435 blocked for more than 144 seconds. Not tainted 6.1.112-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.153 state:D stack:24512 pid:4435 ppid:3784 flags:0x00004004 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 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6b9/0xd80 kernel/locking/mutex.c:747 exfat_sync_fs+0x67/0x100 fs/exfat/super.c:65 iterate_supers+0x127/0x1e0 fs/super.c:757 ksys_sync+0xd7/0x1c0 fs/sync.c:104 __do_sys_sync+0xa/0x10 fs/sync.c:113 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: 0033:0x7f653957dff9 RSP: 002b:00007f653a3c5038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f6539735f80 RCX: 00007f653957dff9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f65395f0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f6539735f80 R15: 00007ffe9e57f4a8 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32b1d0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d32b9d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/27: #0: ffffffff8d32b000 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32b000 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32b000 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494 3 locks held by kworker/0:2/945: #0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc900048f7d20 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e4fa7e8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:104 1 lock held by udevd/3092: 2 locks held by getty/3395: #0: ffff88814b69d098 (&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 3 locks held by kworker/0:4/3681: #0: ffff88802e2d1d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000481fd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e4fa7e8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x16b0 net/ipv6/addrconf.c:4115 2 locks held by kworker/0:8/3710: #0: ffff888017c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90004947d20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 3 locks held by kworker/u4:6/3725: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc900049c7d20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e4fa7e8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263 3 locks held by kworker/1:7/3738: #0: ffff88802e2d1d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90004a57d20 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e4fa7e8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x15/0x30 net/ipv6/addrconf.c:4656 5 locks held by kworker/u4:12/3778: #0: ffff888017e1e938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90004bf7d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e4ee490 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:566 #3: ffffffff8e4fa7e8 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xe5/0x9d0 net/core/dev.c:11381 #4: ffffffff8d3305f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #4: ffffffff8d3305f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4f0/0x930 kernel/rcu/tree_exp.h:962 3 locks held by syz.0.98/4207: 2 locks held by syz.3.153/4435: #0: ffff8880788a00e0 (&type->s_umount_key#56){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:755 #1: ffff88805a0f80e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_sync_fs+0x67/0x100 fs/exfat/super.c:65 1 lock held by syz-executor/5759: #0: ffffffff8e4fa7e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e4fa7e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118 1 lock held by syz.1.509/6021: #0: ffffffff8e4fa7e8 (rtnl_mutex){+.+.}-{3:3}, at: ip_rt_ioctl+0xe6/0x1740 net/ipv4/fib_frontend.c:630 1 lock held by syz.4.515/6027: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 6.1.112-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 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+0x1ae/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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3834 Comm: kworker/u4:13 Not tainted 6.1.112-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: 0x0 (bat_events) RIP: 0010:process_one_work+0x243/0x11d0 kernel/workqueue.c:2215 Code: c8 61 48 0f af 44 24 10 48 c1 e8 3a 48 8b 4c 24 28 4c 8d bc c1 28 01 00 00 4c 89 f8 48 c1 e8 03 48 89 44 24 18 42 80 3c 20 00 <74> 08 4c 89 ff e8 f3 4c 87 00 49 8b 1f 48 85 db 0f 84 d5 00 00 00 RSP: 0018:ffffc90004d7fc60 EFLAGS: 00000046 RAX: 1ffff11002f8f361 RBX: 0000000000000004 RCX: ffff888017c79800 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000000 RBP: ffffc90004d7fde0 R08: ffffffff815ae3fe R09: ffffc90004d7fd28 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffffc90004d7fd20 R15: ffff888017c79b08 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff421f37a8c CR3: 000000000d08e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: 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