INFO: task syz.4.477:10353 blocked for more than 143 seconds. Not tainted 6.12.0-rc3-syzkaller-00217-g4d939780b705 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.477 state:D stack:25024 pid:10353 tgid:10352 ppid:9331 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1843/0x4ae0 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6774 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6831 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752 exfat_sync_fs+0xb0/0x160 fs/exfat/super.c:56 iterate_supers+0xc6/0x190 fs/super.c:934 ksys_sync+0xdb/0x1c0 fs/sync.c:104 __do_sys_sync+0xe/0x20 fs/sync.c:113 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f07abd7dff9 RSP: 002b:00007f07acc64038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f07abf35f80 RCX: 00007f07abd7dff9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f07abdf0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f07abf35f80 R15: 00007fff7ac73b58 Showing all locks held in the system: 3 locks held by kworker/0:0/8: #0: ffff8880b863ea58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:593 #1: ffff8880b8628948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x41d/0x7a0 kernel/sched/psi.c:987 #2: ffff8880b862a718 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x112/0x240 kernel/time/timer.c:1051 4 locks held by kworker/u8:0/11: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000107d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000107d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcc0848 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 #3: ffffffff8e93d378 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #3: ffffffff8e93d378 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976 1 lock held by khungtaskd/30: #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720 2 locks held by kworker/u8:5/955: 3 locks held by kworker/u8:6/964: #0: ffff88802f028148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88802f028148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90003867d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90003867d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcc0848 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4196 2 locks held by dhcpcd/4887: #0: ffff8880683b96c8 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: __netlink_dump_start+0x119/0x790 net/netlink/af_netlink.c:2405 #1: ffffffff8fcc0848 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #1: ffffffff8fcc0848 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_dumpit+0x99/0x200 net/core/rtnetlink.c:6534 2 locks held by getty/4975: #0: ffff88802f3d30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:7/5301: 3 locks held by syz.4.346/9219: 2 locks held by syz.4.477/10353: #0: ffff88807b0660e0 (&type->s_umount_key#94){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807b0660e0 (&type->s_umount_key#94){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff88805119e0e8 (&sbi->s_lock#2){+.+.}-{3:3}, at: exfat_sync_fs+0xb0/0x160 fs/exfat/super.c:56 2 locks held by syz.4.502/10722: #0: ffff88807b0660e0 (&type->s_umount_key#94){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807b0660e0 (&type->s_umount_key#94){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff88805119e0e8 (&sbi->s_lock#2){+.+.}-{3:3}, at: exfat_sync_fs+0xb0/0x160 fs/exfat/super.c:56 2 locks held by syz.0.517/10860: #0: ffff88807b0660e0 (&type->s_umount_key#94){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807b0660e0 (&type->s_umount_key#94){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff88805119e0e8 (&sbi->s_lock#2){+.+.}-{3:3}, at: exfat_sync_fs+0xb0/0x160 fs/exfat/super.c:56 1 lock held by syz-executor/11266: #0: ffffffff8fcc0848 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fcc0848 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 1 lock held by syz.4.545/11296: #0: ffff88807b0660e0 (&type->s_umount_key#94){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807b0660e0 (&type->s_umount_key#94){++++}-{3:3}, at: super_lock+0x196/0x400 fs/super.c:120 1 lock held by syz-executor/11364: #0: ffffffff8fcc0848 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcc0848 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6672 1 lock held by syz.0.574/11456: #0: ffff88807b0660e0 (&type->s_umount_key#94){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807b0660e0 (&type->s_umount_key#94){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 1 lock held by syz-executor/11462: #0: ffffffff8fcc0848 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcc0848 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6672 1 lock held by udevd/11519: #0: ffffffff8eec27c8 (uuid_mutex){+.+.}-{3:3}, at: btrfs_control_ioctl+0x150/0x3e0 fs/btrfs/super.c:2258 1 lock held by syz-executor/11544: #0: ffffffff8fcc0848 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcc0848 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6672 2 locks held by syz.2.548/11597: #0: ffffffff8eec27c8 (uuid_mutex){+.+.}-{3:3}, at: btrfs_get_tree_super fs/btrfs/super.c:1835 [inline] #0: ffffffff8eec27c8 (uuid_mutex){+.+.}-{3:3}, at: btrfs_get_tree+0x2dc/0x1920 fs/btrfs/super.c:2114 #1: ffffffff8e9f8fe8 (lock#3){+.+.}-{3:3}, at: __lru_add_drain_all+0x66/0x560 mm/swap.c:843 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc3-syzkaller-00217-g4d939780b705 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 9219 Comm: syz.4.346 Not tainted 6.12.0-rc3-syzkaller-00217-g4d939780b705 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__lock_is_held kernel/locking/lockdep.c:5566 [inline] RIP: 0010:lock_is_held_type+0x9e/0x190 kernel/locking/lockdep.c:5897 Code: 0a 8c e8 65 1b 00 00 65 ff 05 ae af 44 74 41 83 bd d8 0a 00 00 00 7e 47 4c 89 eb 48 81 c3 e0 0a 00 00 31 ed 48 83 fd 31 73 24 <48> 89 df 4c 89 fe e8 77 02 00 00 85 c0 75 2a 48 ff c5 49 63 85 d8 RSP: 0018:ffffc9000369f398 EFLAGS: 00000083 RAX: 0000000000000003 RBX: ffff88802f300b08 RCX: ffff88802f300000 RDX: 0000000000000000 RSI: ffffffff8e937d60 RDI: ffff88802f300ae0 RBP: 0000000000000001 R08: ffffffff82200e23 R09: 1ffffffff2037a75 R10: dffffc0000000000 R11: fffffbfff2037a76 R12: 0000000000000246 R13: ffff88802f300000 R14: 00000000ffffffff R15: ffffffff8e937d60 FS: 00007f4b3f11a6c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555577602608 CR3: 0000000078840000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:249 [inline] __might_resched+0xf4/0x780 kernel/sched/core.c:8600 might_alloc include/linux/sched/mm.h:321 [inline] bdev_getblk+0x89/0x550 fs/buffer.c:1433 __bread_gfp+0x86/0x400 fs/buffer.c:1491 sb_bread include/linux/buffer_head.h:346 [inline] exfat_get_dentry+0x53b/0x730 fs/exfat/dir.c:691 exfat_readdir fs/exfat/dir.c:121 [inline] exfat_iterate+0xb69/0x3390 fs/exfat/dir.c:261 wrap_directory_iterator+0x91/0xd0 fs/readdir.c:65 iterate_dir+0x571/0x800 fs/readdir.c:108 __do_sys_getdents64 fs/readdir.c:407 [inline] __se_sys_getdents64+0x1d3/0x4a0 fs/readdir.c:392 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4b3e37dff9 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:00007f4b3f11a038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00007f4b3e535f80 RCX: 00007f4b3e37dff9 RDX: 0000000000001000 RSI: 0000000020000f80 RDI: 0000000000000006 RBP: 00007f4b3e3f0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f4b3e535f80 R15: 00007fff60c4ce58