INFO: task syz.0.97:4689 blocked for more than 144 seconds. Not tainted 6.1.129-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.97 state:D stack:27256 pid:4689 ppid:4250 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5243 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6560 schedule+0xbf/0x180 kernel/sched/core.c:6636 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6695 __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 sync_filesystem+0x1bc/0x220 fs/sync.c:66 exfat_reconfigure+0x79/0xa0 fs/exfat/super.c:739 reconfigure_super+0x43a/0x870 fs/super.c:977 do_remount fs/namespace.c:2712 [inline] path_mount+0xe69/0x1090 fs/namespace.c:3378 do_mount fs/namespace.c:3399 [inline] __do_sys_mount fs/namespace.c:3607 [inline] __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3584 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: 0033:0x7f002cf8e90a RSP: 002b:00007f002dd4de68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f002dd4def0 RCX: 00007f002cf8e90a RDX: 0000400000000180 RSI: 0000400000000380 RDI: 0000000000000000 RBP: 0000400000000180 R08: 00007f002dd4def0 R09: 0000000002042023 R10: 0000000002042023 R11: 0000000000000246 R12: 0000400000000380 R13: 00007f002dd4deb0 R14: 0000000000000000 R15: 00004000000002c0 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32e850 (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: ffffffff8d32f050 (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/28: #0: ffffffff8d32e680 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32e680 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32e680 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510 2 locks held by getty/4008: #0: ffff88814d19a098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000325e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x54a/0x1620 drivers/tty/n_tty.c:2198 3 locks held by syz.0.97/4684: 2 locks held by syz.0.97/4689: #0: ffff888079afa0e0 (&type->s_umount_key#55){+.+.}-{3:3}, at: do_remount fs/namespace.c:2709 [inline] #0: ffff888079afa0e0 (&type->s_umount_key#55){+.+.}-{3:3}, at: path_mount+0xe26/0x1090 fs/namespace.c:3378 #1: ffff88807941c0e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_sync_fs+0x67/0x100 fs/exfat/super.c:65 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.129-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 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+0x1ca/0x430 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: 4957 Comm: kworker/u4:16 Not tainted 6.1.129-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:check_wait_context kernel/locking/lockdep.c:4739 [inline] RIP: 0010:__lock_acquire+0x642/0x1f80 kernel/locking/lockdep.c:4999 Code: 41 8b 2c 24 41 89 ec ff cd 0f 88 a2 00 00 00 89 eb 83 fd 31 73 79 48 8d 04 9b 48 8d 5c c6 20 48 89 d8 48 c1 e8 03 0f b6 04 10 <84> c0 75 18 8b 1b 41 0f b6 04 17 84 c0 75 31 41 33 1e f7 c3 00 60 RSP: 0018:ffffc9000d7779a0 EFLAGS: 00000806 RAX: 0000000000000000 RBX: ffff88802ebe0b28 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: ffff88802ebe0ae0 RDI: ffffffff912b6260 RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff2256c4d R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000002 R13: ffff88802ebe0000 R14: ffff88802ebe0b50 R15: 1ffff11005d7c16a FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f368d378ab8 CR3: 000000007452a000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xe8/0x610 net/batman-adv/network-coding.c:719 process_one_work+0x917/0x1260 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