INFO: task syz.2.420:7785 blocked for more than 143 seconds. Not tainted syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.420 state:D stack:20056 pid:7785 tgid:7785 ppid:5837 task_flags:0x40064c flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 wb_wait_for_completion+0x15f/0x260 fs/fs-writeback.c:216 sync_inodes_sb+0x1bb/0xa10 fs/fs-writeback.c:2873 sync_filesystem+0x17a/0x230 fs/sync.c:64 ovl_sync_fs+0x12f/0x160 fs/overlayfs/super.c:254 sync_filesystem+0x1cf/0x230 fs/sync.c:66 generic_shutdown_super+0x6f/0x2c0 fs/super.c:621 kill_anon_super+0x3b/0x70 fs/super.c:1281 deactivate_locked_super+0xbc/0x130 fs/super.c:473 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1327 task_work_run+0x1d4/0x260 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x6b5/0x2300 kernel/exit.c:966 do_group_exit+0x21c/0x2d0 kernel/exit.c:1107 get_signal+0x1285/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:40 [inline] exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] irqentry_exit_to_user_mode+0x7e/0x110 kernel/entry/common.c:73 exc_page_fault+0xab/0x100 arch/x86/mm/fault.c:1535 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7fd44ce4f987 RSP: 002b:00007fd44de94120 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 000000000000000b RCX: 00007fd44cf8efc9 RDX: 00007fd44de94140 RSI: 00007fd44de94270 RDI: 000000000000000b RBP: 00007fd44d011f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007fd44d1e6038 R14: 00007fd44d1e5fa0 R15: 00007ffff943ed28 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: #0: ffffffff8df430b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #0: ffffffff8df430b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957 1 lock held by khungtaskd/31: #0: ffffffff8df3d620 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3d620 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df3d620 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 5 locks held by kworker/u9:0/52: #0: ffff888049ce8148 ((wq_completion)hci6){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff888049ce8148 ((wq_completion)hci6){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffff8880b8924048 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff88807bc7c6d8 (&hdev->cmd_sync_work_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x295/0x3a0 net/bluetooth/hci_sync.c:315 #3: ffff88807bc7c0b8 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x242/0xe30 net/bluetooth/hci_sync.c:5684 #4: ffff88807bc7c6d8 (&hdev->cmd_sync_work_lock){+.+.}-{4:4}, at: hci_cmd_sync_dequeue+0x44/0x340 net/bluetooth/hci_sync.c:893 5 locks held by kworker/u8:5/1158: 2 locks held by getty/5584: #0: ffff88814d4f50a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036ce2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 4 locks held by kworker/u8:10/6060: 3 locks held by syz.2.420/7785: #0: ffff88806b36a0e0 (&type->s_umount_key#88){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88806b36a0e0 (&type->s_umount_key#88){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88806b36a0e0 (&type->s_umount_key#88){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505 #1: ffff88803075a0e0 (&type->s_umount_key#78){++++}-{4:4}, at: ovl_sync_fs+0x127/0x160 fs/overlayfs/super.c:253 #2: ffff888142bfe820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline] #2: ffff888142bfe820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2871 1 lock held by syz-executor/8964: #0: ffff8880b883a058 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:646 2 locks held by syz.4.983/9638: 1 lock held by syz.8.995/9700: #0: ffffffff8f2cb648 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff8f2cb648 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436 1 lock held by syz.8.995/9701: #0: ffffffff8f2cb648 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f2cb648 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x71c/0xb70 net/core/rtnetlink.c:6957 1 lock held by syz.8.995/9703: #0: ffffffff8f2cb648 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] ffffffff8f2cb648 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x71c/0xb70 net/core/rtnetlink.c:6957 1 lock held by syz.8.995/9704: #0: ffffffff8f2cb648 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f2cb648 (rtnl_mutex){+.+.}-{4:4}, at: dev_ioctl+0x7a4/0x1150 net/core/dev_ioctl.c:837 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline] watchdog+0xf60/0xfa0 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6060 Comm: kworker/u8:10 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: writeback wb_workfn (flush-7:2) RIP: 0010:match_held_lock+0x7b/0xc0 kernel/locking/lockdep.c:5337 Code: c7 c2 30 e3 16 93 48 29 d0 48 c1 f8 03 48 ba 29 5c 8f c2 f5 28 5c 8f 48 0f af d0 bb 01 00 00 00 48 39 ca 74 02 31 db 89 d8 5b <41> 5e e9 89 f8 c9 f5 cc 90 e8 c7 da 3f f9 85 c0 74 22 83 3d 00 c4 RSP: 0018:ffffc900000078d8 EFLAGS: 00000046 RAX: 0000000000000001 RBX: ffff888031b6c8a0 RCX: 679652f7add5da00 RDX: 0000000000000005 RSI: ffff8880b883a058 RDI: ffff888031b6c8a0 RBP: 00000000ffffffff R08: ffffffff8f7cdc77 R09: 1ffffffff1ef9b8e R10: dffffc0000000000 R11: fffffbfff1ef9b8f R12: 0000000000000046 R13: ffff888031b6bc80 R14: ffff8880b883a058 R15: 0000000000000006 FS: 0000000000000000(0000) GS:ffff88812613d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9f567b3ad8 CR3: 00000000760fb000 CR4: 0000000000350ef0 Call Trace: __lock_is_held kernel/locking/lockdep.c:5601 [inline] lock_is_held_type+0xa8/0x190 kernel/locking/lockdep.c:5940 lock_is_held include/linux/lockdep.h:249 [inline] lockdep_assert_rq_held kernel/sched/sched.h:1538 [inline] rq_clock_pelt kernel/sched/pelt.h:71 [inline] cfs_rq_clock_pelt kernel/sched/pelt.h:179 [inline] update_load_avg+0xdb/0x1880 kernel/sched/fair.c:4718 enqueue_entity kernel/sched/fair.c:5261 [inline] enqueue_task_fair+0x2d2/0x2920 kernel/sched/fair.c:6976 enqueue_task+0x75/0x420 kernel/sched/core.c:2092 activate_task kernel/sched/core.c:2134 [inline] ttwu_do_activate+0x1f3/0x870 kernel/sched/core.c:3706 ttwu_queue kernel/sched/core.c:3969 [inline] try_to_wake_up+0x721/0x12b0 kernel/sched/core.c:4293 call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403 handle_softirqs+0x286/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2034 [inline] RIP: 0010:vprintk_emit+0x49d/0x590 kernel/printk/printk.c:2422 Code: 0f 84 34 ff ff ff e8 d2 ed 1f 00 fb eb 44 e8 ca ed 1f 00 e8 45 29 a6 09 4d 85 f6 74 94 e8 bb ed 1f 00 fb 48 c7 c7 00 16 f3 8d <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 0b 39 RSP: 0018:ffffc9000b28dea0 EFLAGS: 00000293 RAX: ffffffff81a018d5 RBX: ffffffff81a0172e RCX: ffff888031b6bc80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8df31600 RBP: ffffc9000b28dfb0 R08: ffffffff8f7cdc77 R09: 1ffffffff1ef9b8e R10: dffffc0000000000 R11: fffffbfff1ef9b8f R12: 0000000000000000 R13: 000000000000004b R14: 0000000000000200 R15: 1ffff92001651bd8 _printk+0xcf/0x120 kernel/printk/printk.c:2448 print_hex_dump+0x1a8/0x260 lib/hexdump.c:285 xfs_hex_dump+0x3d/0x50 fs/xfs/xfs_message.c:110 xfs_buf_verifier_error+0x1cc/0x2a0 fs/xfs/xfs_error.c:310 xfs_agf_read_verify+0x16e/0x1f0 fs/xfs/libxfs/xfs_alloc.c:-1 __xfs_buf_ioend+0x342/0x6f0 fs/xfs/xfs_buf.c:1174 xfs_buf_iowait+0x167/0x480 fs/xfs/xfs_buf.c:1381 _xfs_buf_read fs/xfs/xfs_buf.c:643 [inline] xfs_buf_read_map+0x335/0xa50 fs/xfs/xfs_buf.c:709 xfs_trans_read_buf_map+0x1d7/0x8e0 fs/xfs/xfs_trans_buf.c:304 xfs_trans_read_buf fs/xfs/xfs_trans.h:210 [inline] xfs_read_agf+0x281/0x5c0 fs/xfs/libxfs/xfs_alloc.c:3376 xfs_alloc_read_agf+0x17c/0xb70 fs/xfs/libxfs/xfs_alloc.c:3411 xfs_bmap_longest_free_extent+0x77/0x150 fs/xfs/libxfs/xfs_bmap.c:3158 xfs_filestream_pick_ag fs/xfs/xfs_filestream.c:81 [inline] xfs_filestream_create_association fs/xfs/xfs_filestream.c:297 [inline] xfs_filestream_select_ag+0x81b/0x1b00 fs/xfs/xfs_filestream.c:360 xfs_bmap_btalloc_filestreams fs/xfs/libxfs/xfs_bmap.c:3544 [inline] xfs_bmap_btalloc fs/xfs/libxfs/xfs_bmap.c:3661 [inline] xfs_bmapi_allocate+0x1651/0x2e00 fs/xfs/libxfs/xfs_bmap.c:3938 xfs_bmapi_convert_one_delalloc fs/xfs/libxfs/xfs_bmap.c:4447 [inline] xfs_bmapi_convert_delalloc+0x7e2/0x1430 fs/xfs/libxfs/xfs_bmap.c:4503 xfs_map_blocks fs/xfs/xfs_aops.c:445 [inline] xfs_writeback_range+0x674/0xf70 fs/xfs/xfs_aops.c:489 iomap_writeback_range fs/iomap/buffered-io.c:1593 [inline] iomap_writeback_folio+0xe75/0x1c80 fs/iomap/buffered-io.c:1718 iomap_writepages+0x162/0x2d0 fs/iomap/buffered-io.c:1770 xfs_vm_writepages+0x296/0x310 fs/xfs/xfs_aops.c:701 do_writepages+0x32e/0x550 mm/page-writeback.c:2604 __writeback_single_inode+0x145/0xff0 fs/fs-writeback.c:1719 writeback_sb_inodes+0x6c7/0x1010 fs/fs-writeback.c:2015 wb_writeback+0x43b/0xaf0 fs/fs-writeback.c:2195 wb_do_writeback fs/fs-writeback.c:2342 [inline] wb_workfn+0x409/0xef0 fs/fs-writeback.c:2382 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245