INFO: task syz.2.99:6118 blocked for more than 143 seconds. Not tainted 6.10.0-rc6-syzkaller-00210-gd270dd21bee0 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.99 state:D stack:16000 pid:6118 tgid:6086 ppid:5629 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x1796/0x49d0 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6837 io_schedule+0x8d/0x110 kernel/sched/core.c:9043 folio_wait_bit_common+0x882/0x12b0 mm/filemap.c:1307 folio_wait_writeback+0xe7/0x1e0 mm/page-writeback.c:3162 __filemap_fdatawait_range+0x181/0x410 mm/filemap.c:532 filemap_fdatawait_range+0x25/0x40 mm/filemap.c:559 filemap_fdatawait include/linux/pagemap.h:48 [inline] __writeback_single_inode+0x1f0/0x10b0 fs/fs-writeback.c:1661 writeback_single_inode+0x21b/0x7a0 fs/fs-writeback.c:1772 sync_inode_metadata+0xca/0x130 fs/fs-writeback.c:2842 bch2_fsync+0xb6/0x130 fs/bcachefs/fs-io.c:200 generic_write_sync include/linux/fs.h:2794 [inline] bch2_buffered_write fs/bcachefs/fs-io-buffered.c:1128 [inline] bch2_write_iter+0x262e/0x2840 fs/bcachefs/fs-io-buffered.c:1136 new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa72/0xc90 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 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: 0033:0x7fd306975bd9 RSP: 002b:00007fd3077ec048 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fd306b04038 RCX: 00007fd306975bd9 RDX: 0000000000000020 RSI: 00000000200007c0 RDI: 0000000000000004 RBP: 00007fd3069e4aa1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007fd306b04038 R15: 00007ffea07b35c8 Showing all locks held in the system: 3 locks held by kworker/u8:1/12: #0: ffff888015089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3223 [inline] #0: ffff888015089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3329 #1: ffff8880b9528948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:988 #2: ffffffff949c9a80 (&obj_hash[i].lock){-.-.}-{2:2}, at: __debug_check_no_obj_freed lib/debugobjects.c:978 [inline] #2: ffffffff949c9a80 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_check_no_obj_freed+0x234/0x580 lib/debugobjects.c:1019 1 lock held by khungtaskd/30: #0: ffffffff8e333f20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8e333f20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8e333f20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 3 locks held by kworker/0:2/784: #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3223 [inline] #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3329 #1: ffff8880b9428948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:988 #2: ffff888058e1e538 (&idev->mc_lock){+.+.}-{3:3}, at: mld_dad_work+0x3c/0x500 net/ipv6/mcast.c:2258 2 locks held by kworker/u8:7/1057: #0: ffff88801b2b0948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3223 [inline] #0: ffff88801b2b0948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3329 #1: ffffc900040cfd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3224 [inline] #1: ffffc900040cfd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3329 2 locks held by getty/4836: #0: ffff88802b2dc0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f0e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2211 3 locks held by kworker/0:4/5127: #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3223 [inline] #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3329 #1: ffffc9000430fd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3224 [inline] #1: ffffc9000430fd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3329 #2: ffff88804eb8a240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x2d1/0x4130 drivers/net/netdevsim/fib.c:1489 2 locks held by kworker/1:3/5132: #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3223 [inline] #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3329 #1: ffffc90003fbfd00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3224 [inline] #1: ffffc90003fbfd00 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3329 3 locks held by kworker/0:7/5142: #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3223 [inline] #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3329 #1: ffffc9000437fd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3224 [inline] #1: ffffc9000437fd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3329 #2: ffff88807bbbe240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x2d1/0x4130 drivers/net/netdevsim/fib.c:1489 1 lock held by syz.2.99/6087: #0: ffff88807da26420 (sb_writers#22){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x220 fs/splice.c:1163 2 locks held by syz.2.99/6118: #0: ffff8880235759c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x24e/0x310 fs/file.c:1191 #1: ffff88807da26420 (sb_writers#22){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2854 [inline] #1: ffff88807da26420 (sb_writers#22){.+.+}-{0:0}, at: vfs_write+0x227/0xc90 fs/read_write.c:586 2 locks held by syz.0.184/6936: #0: ffff88807da260e0 (&type->s_umount_key#97){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807da260e0 (&type->s_umount_key#97){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff88807da247d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:388 [inline] #1: ffff88807da247d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xb20 fs/fs-writeback.c:2790 2 locks held by syz.0.184/6937: #0: ffff88807da260e0 (&type->s_umount_key#97){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807da260e0 (&type->s_umount_key#97){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff88807da247d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:388 [inline] #1: ffff88807da247d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xb20 fs/fs-writeback.c:2790 2 locks held by syz.2.262/7640: #0: ffff88807da260e0 (&type->s_umount_key#97){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807da260e0 (&type->s_umount_key#97){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff88807da247d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:388 [inline] #1: ffff88807da247d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xb20 fs/fs-writeback.c:2790 1 lock held by syz-executor/7689: #0: ffffffff8e3392f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #0: ffffffff8e3392f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:939 3 locks held by syz-executor/7691: #0: ffff888022940d88 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:510 [inline] #0: ffff888022940d88 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2728 #1: ffff888022940078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x494/0xf60 net/bluetooth/hci_sync.c:5063 #2: ffffffff8f73f008 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1982 [inline] #2: ffffffff8f73f008 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2593 1 lock held by syz-executor/7782: #0: ffffffff8e3392f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #0: ffffffff8e3392f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:939 1 lock held by dhcpcd-run-hook/7902: #0: ffff8880b953e758 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 30 Comm: khungtaskd Not tainted 6.10.0-rc6-syzkaller-00210-gd270dd21bee0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 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+0xfde/0x1020 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 PID: 7782 Comm: syz-executor Not tainted 6.10.0-rc6-syzkaller-00210-gd270dd21bee0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0010:check_kcov_mode kernel/kcov.c:184 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x37/0x70 kernel/kcov.c:207 Code: 80 d4 03 00 65 8b 15 b0 ad 6d 7e f7 c2 00 01 ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 1c 16 00 00 00 74 2c 8b 91 f8 15 00 00 <83> fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc RSP: 0018:ffffc900043bf460 EFLAGS: 00000246 RAX: ffffffff8140f6df RBX: 0000000000000003 RCX: ffff888022490000 RDX: 0000000000000000 RSI: ffffffff8e1a1360 RDI: 0000000000000003 RBP: ffffffff90cf180c R08: 0000000000000003 R09: ffffffff8140f6b2 R10: 0000000000000002 R11: ffff888022490000 R12: ffffffff90274a44 R13: dffffc0000000000 R14: 1ffff92000877ea8 R15: ffffffff90cf1808 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055989d960131 CR3: 000000000e132000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0x6ef/0x2a00 arch/x86/kernel/unwind_orc.c:505 arch_stack_walk+0x151/0x1b0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 save_stack+0xfb/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x75/0x3f0 mm/page_owner.c:297 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1093 [inline] free_unref_page+0xd19/0xea0 mm/page_alloc.c:2588 vfree+0x186/0x2e0 mm/vmalloc.c:3355 kcov_put kernel/kcov.c:429 [inline] kcov_close+0x2b/0x50 kernel/kcov.c:525 __fput+0x24a/0x8a0 fs/file_table.c:422 task_work_run+0x24f/0x310 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa27/0x27e0 kernel/exit.c:876 do_group_exit+0x207/0x2c0 kernel/exit.c:1025 get_signal+0x16a1/0x1740 kernel/signal.c:2909 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x360 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f961a57796c Code: Unable to access opcode bytes at 0x7f961a577942. RSP: 002b:00007ffcee65ba30 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: 0000000000000040 RBX: 00007f961b234620 RCX: 00007f961a57796c RDX: 0000000000000040 RSI: 00007f961b234670 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffcee65ba84 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f961b234670 R15: 0000000000000000