INFO: task syz-executor:5825 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:19496 pid:5825 tgid:5825 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 wb_wait_for_completion+0x360/0x680 fs/fs-writeback.c:226 sync_inodes_sb+0x1c9/0xb40 fs/fs-writeback.c:2894 sync_filesystem+0x17a/0x230 fs/sync.c:64 generic_shutdown_super+0x6f/0x2c0 fs/super.c:622 kill_block_super+0x44/0x90 fs/super.c:1722 xfs_kill_sb+0x15/0x50 fs/xfs/xfs_super.c:2297 deactivate_locked_super+0xbc/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1318 task_work_run+0x1d4/0x260 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:44 [inline] exit_to_user_mode_loop+0xff/0x4f0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2e3/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0bb8d90a77 RSP: 002b:00007fffcd1ba158 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f0bb8e13d7d RCX: 00007f0bb8d90a77 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fffcd1ba210 RBP: 00007fffcd1ba210 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fffcd1bb2a0 R13: 00007f0bb8e13d7d R14: 00000000000322b0 R15: 00007fffcd1bb2e0 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/u8:11/3562: #0: ffff8880b863a918 (&rq->__lock ){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:647 #1: ffff8880b8724588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 2 locks held by getty/5584: #0: ffff88814eca50a0 (&tty->ldisc_sem){++++}-{0:0} , at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4} , at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/5825: #0: ffff88802a71c0e0 (&type->s_umount_key#66){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] ffff88802a71c0e0 (&type->s_umount_key#66){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] ffff88802a71c0e0 (&type->s_umount_key#66){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffff888024c3e820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff888024c3e820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40 fs/fs-writeback.c:2892 9 locks held by kworker/u8:15/5987: 2 locks held by syz.4.361/7381: #0: ffff888028ea0420 (sb_writers#3){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1160 #1: ffff88802a71c0e0 (&type->s_umount_key#66){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #1: ffff88802a71c0e0 (&type->s_umount_key#66){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 1 lock held by syz.0.621/8585: #0: ffffffff8df47400 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3816 ============================================= 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 10/25/2025 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] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xf95/0xfe0 kernel/hung_task.c:515 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5987 Comm: kworker/u8:15 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: writeback wb_workfn (flush-7:2) RIP: 0010:__lock_is_held kernel/locking/lockdep.c:5598 [inline] RIP: 0010:lock_is_held_type+0xd4/0x190 kernel/locking/lockdep.c:5940 Code: 75 2a 49 ff c7 49 63 85 28 0b 00 00 48 83 c3 28 49 39 c7 7c d8 eb 11 48 c7 c7 50 1f e1 8d 4c 89 fe e8 30 7a 6c f9 eb cb 31 db 1c 83 fd ff 74 12 31 c0 f6 43 22 03 0f 95 c0 31 db 39 c5 0f 94 RSP: 0018:ffffc90000007ba8 EFLAGS: 00000046 RAX: 0000000000000006 RBX: 0000000000000000 RCX: a55781ea070f5d00 RDX: 00000000d7fe226f RSI: ffffffff8de06cc8 RDI: ffff88802ebe0bf8 RBP: 00000000ffffffff R08: ffffffff81954b89 R09: ffffffff8df419e0 R10: dffffc0000000000 R11: ffffffff81954880 R12: 0000000000000046 R13: ffff88802ebe0000 R14: ffffffff8de06cc8 R15: 0000000000000006 FS: 0000000000000000(0000) GS:ffff888125e3a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe71dbb42f8 CR3: 000000001f794000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:249 [inline] select_task_rq_fair+0x3da/0x3570 kernel/sched/fair.c:8551 select_task_rq kernel/sched/core.c:3497 [inline] try_to_wake_up+0x4d8/0x12b0 kernel/sched/core.c:4206 hrtimer_wakeup+0x4e/0x60 kernel/time/hrtimer.c:2013 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x51c/0xc30 kernel/time/hrtimer.c:1841 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline] __sysvec_apic_timer_interrupt+0x102/0x3e0 arch/x86/kernel/apic/apic.c:1062 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2037 [inline] RIP: 0010:vprintk_emit+0x4d0/0x5f0 kernel/printk/printk.c:2425 Code: 0f 84 34 ff ff ff e8 4f 62 20 00 fb eb 44 e8 47 62 20 00 e8 62 90 b9 09 4d 85 f6 74 94 e8 38 62 20 00 fb 48 c7 c7 a0 58 f3 8d <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 28 26 RSP: 0018:ffffc90005275d40 EFLAGS: 00000293 RAX: ffffffff81a15158 RBX: ffffffff81a14fb1 RCX: ffff88802ebe0000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8df358a0 RBP: ffffc90005275e50 R08: ffffffff8f81f577 R09: 1ffffffff1f03eae R10: dffffc0000000000 R11: fffffbfff1f03eaf R12: 0000000000000000 R13: 0000000000000064 R14: 0000000000000200 R15: 1ffff92000a4ebac _printk+0xcf/0x120 kernel/printk/printk.c:2451 __xfs_printk fs/xfs/xfs_message.c:24 [inline] _xfs_alert_tag+0x1cb/0x2d0 fs/xfs/xfs_message.c:74 xfs_buf_verifier_error+0x150/0x2a0 fs/xfs/xfs_error.c:299 xfs_allocbt_read_verify+0x5f/0xe0 fs/xfs/libxfs/xfs_alloc_btree.c:-1 __xfs_buf_ioend+0x332/0x6d0 fs/xfs/xfs_buf.c:1174 xfs_buf_iowait+0x143/0x440 fs/xfs/xfs_buf.c:1381 _xfs_buf_read fs/xfs/xfs_buf.c:643 [inline] xfs_buf_read_map+0x325/0xa30 fs/xfs/xfs_buf.c:709 xfs_trans_read_buf_map+0x1d7/0x8a0 fs/xfs/xfs_trans_buf.c:304 xfs_trans_read_buf fs/xfs/xfs_trans.h:212 [inline] xfs_btree_read_buf_block+0x290/0x470 fs/xfs/libxfs/xfs_btree.c:1402 xfs_btree_lookup_get_block+0x28d/0x500 fs/xfs/libxfs/xfs_btree.c:1907 xfs_btree_lookup+0x4e1/0x1410 fs/xfs/libxfs/xfs_btree.c:2018 xfs_alloc_lookup fs/xfs/libxfs/xfs_alloc.c:166 [inline] xfs_alloc_lookup_ge fs/xfs/libxfs/xfs_alloc.c:198 [inline] xfs_alloc_cur_setup fs/xfs/libxfs/xfs_alloc.c:966 [inline] xfs_alloc_ag_vextent_near+0x447/0x11d0 fs/xfs/libxfs/xfs_alloc.c:1705 xfs_alloc_vextent_near_bno+0x2e7/0x560 fs/xfs/libxfs/xfs_alloc.c:3962 xfs_bmap_btalloc_filestreams fs/xfs/libxfs/xfs_bmap.c:3566 [inline] xfs_bmap_btalloc fs/xfs/libxfs/xfs_bmap.c:3661 [inline] xfs_bmapi_allocate+0x1af7/0x2e00 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+0x674/0xf30 fs/xfs/xfs_aops.c:489 iomap_writeback_range fs/iomap/buffered-io.c:1724 [inline] iomap_writeback_folio+0x1408/0x23f0 fs/iomap/buffered-io.c:1842 iomap_writepages+0x162/0x2d0 fs/iomap/buffered-io.c:1902 xfs_vm_writepages+0x296/0x310 fs/xfs/xfs_aops.c:701 do_writepages+0x32e/0x550 mm/page-writeback.c:2598 __writeback_single_inode+0x133/0x1240 fs/fs-writeback.c:1737 writeback_sb_inodes+0x93a/0x1870 fs/fs-writeback.c:2030 wb_writeback+0x42b/0xaa0 fs/fs-writeback.c:2216 wb_do_writeback fs/fs-writeback.c:2363 [inline] wb_workfn+0x3f9/0xed0 fs/fs-writeback.c:2403 process_one_work+0x93a/0x15a0 kernel/workqueue.c:3261 process_scheduled_works kernel/workqueue.c:3344 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246