INFO: task syz.0.199:5018 blocked for more than 143 seconds. Not tainted 5.15.179-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.199 state:D stack:19896 pid: 5018 ppid: 4166 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5029 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6375 schedule+0x11b/0x1f0 kernel/sched/core.c:6458 wb_wait_for_completion+0x164/0x290 fs/fs-writeback.c:191 sync_inodes_sb+0x293/0xab0 fs/fs-writeback.c:2770 sync_filesystem+0x16b/0x220 fs/sync.c:64 generic_shutdown_super+0x6b/0x310 fs/super.c:448 kill_block_super+0x7a/0xe0 fs/super.c:1427 deactivate_locked_super+0xa0/0x110 fs/super.c:335 cleanup_mnt+0x44e/0x500 fs/namespace.c:1143 task_work_run+0x129/0x1a0 kernel/task_work.c:188 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0x6a3/0x2480 kernel/exit.c:874 do_group_exit+0x144/0x310 kernel/exit.c:996 get_signal+0xc66/0x14e0 kernel/signal.c:2900 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f1338534169 RSP: 002b:00007f133639d038 EFLAGS: 00000246 ORIG_RAX: 000000000000001c RAX: ffffffffffffff8b RBX: 00007f133874cfa0 RCX: 00007f1338534169 RDX: 0000000000000009 RSI: 000000000060000b RDI: 0000200000000000 RBP: 00007f13385b52a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f133874cfa0 R15: 00007ffc56009ad8 Showing all locks held in the system: 4 locks held by kworker/u4:0/9: #0: ffff888019f98938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90000ce7d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffff88801a38a650 (sb_internal#2){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x20f/0x1180 fs/xfs/libxfs/xfs_bmap.c:4573 #3: ffff8880603ecbe8 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_bmapi_convert_delalloc+0x23c/0x1180 fs/xfs/libxfs/xfs_bmap.c:4578 1 lock held by khungtaskd/27: #0: ffffffff8cb1f4e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/3925: #0: ffff88814d478098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900026362e8 ( &ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158 3 locks held by kworker/1:4/4210: #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000314fd20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8cb23aa8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #2: ffffffff8cb23aa8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:845 3 locks held by kworker/1:5/4213: #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000317fd20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8cb23aa8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #2: ffffffff8cb23aa8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:845 2 locks held by kworker/1:10/4797: #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000324fd20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by kworker/1:19/4987: #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000357fd20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by kworker/u4:8/4991: #0: ffff888017479138 ((wq_completion)events_unbound ){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000356fd20 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by syz.0.199/5018: #0: ffff88801a38a0e0 (&type->s_umount_key#53){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365 #1: ffff8881475f67d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff8881475f67d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xab0 fs/fs-writeback.c:2768 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.179-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe72/0xeb0 kernel/hung_task.c:369 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 11990 Comm: dhcpcd-run-hook Not tainted 5.15.179-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:raw_read_seqcount_latch_retry include/linux/seqlock.h:717 [inline] RIP: 0010:latch_tree_find include/linux/rbtree_latch.h:209 [inline] RIP: 0010:bpf_ksym_find kernel/bpf/core.c:692 [inline] RIP: 0010:is_bpf_text_address+0x1aa/0x260 kernel/bpf/core.c:726 Code: dc 54 f3 ff e9 5f ff ff ff e8 d2 54 f3 ff 31 ed eb 0e e8 c9 54 f3 ff 31 ed eb 09 e8 c0 54 f3 ff 4c 8b 3c 24 8b 05 76 ab f3 0a <44> 39 f8 74 0a e8 ac 54 f3 ff e9 e8 fe ff ff e8 d2 bc b2 08 89 c3 RSP: 0000:ffffc900034df280 EFLAGS: 00000246 RAX: 00000000000001e8 RBX: 0000000000000000 RCX: ffff888026ccbb80 RDX: 0000000000000000 RSI: ffffffff8af9fa60 RDI: ffffffff8af9fa20 RBP: 0000000000000000 R08: ffffffff818d468d R09: fffffbfff2131e19 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: ffffffff816e2db0 R14: 00007f9b05e0e99f R15: 00000000000001e8 FS: 00007f9b05cd4380(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffdaab932d8 CR3: 0000000064e1e000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: kernel_text_address kernel/extable.c:151 [inline] __kernel_text_address+0x94/0x100 kernel/extable.c:105 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323 arch_stack_walk+0xf3/0x140 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122 save_stack+0xf6/0x1e0 mm/page_owner.c:119 __set_page_owner+0x37/0x300 mm/page_owner.c:181 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x3b78/0x3d40 mm/page_alloc.c:4192 __alloc_pages+0x272/0x700 mm/page_alloc.c:5466 alloc_pages_vma+0x39a/0x800 mm/mempolicy.c:2146 wp_page_copy+0x24e/0x2070 mm/memory.c:3056 handle_pte_fault mm/memory.c:4668 [inline] __handle_mm_fault mm/memory.c:4785 [inline] handle_mm_fault+0x2a3d/0x5960 mm/memory.c:4883 do_user_addr_fault arch/x86/mm/fault.c:1357 [inline] handle_page_fault arch/x86/mm/fault.c:1445 [inline] exc_page_fault+0x271/0x700 arch/x86/mm/fault.c:1501 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 RIP: 0033:0x7f9b05e0e99f Code: 00 eb 1c 48 89 96 c0 02 00 00 48 89 96 c8 02 00 00 48 89 83 90 10 00 00 48 89 83 88 10 00 00 4c 89 ea 44 89 f6 bf 01 00 00 00 26 04 00 00 eb 34 48 8b 2d 5b 44 0f 00 64 44 8b 7d 00 84 db 75 RSP: 002b:00007ffdaab932e0 EFLAGS: 00010202 RAX: 00007f9b05cd4640 RBX: 00007f9b06006000 RCX: 00007f9b06007098 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 0000557ffaa4bfd0 R08: 0000000000000000 R09: 0000000000000000 R10: 00007f9b06007088 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000024