INFO: task kworker/u8:3:51 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-11558-g075dbe9f6e3c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:3 state:D stack:20664 pid:51 tgid:51 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-bcachefs-1) Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1843/0x4ae0 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 io_schedule+0x8d/0x110 kernel/sched/core.c:7552 folio_wait_bit_common+0x882/0x12b0 mm/filemap.c:1309 folio_lock include/linux/pagemap.h:1148 [inline] writeback_get_folio mm/page-writeback.c:2496 [inline] writeback_iter+0x992/0x18d0 mm/page-writeback.c:2590 write_cache_pages+0xb1/0x230 mm/page-writeback.c:2639 bch2_writepages+0x14f/0x380 fs/bcachefs/fs-io-buffered.c:639 do_writepages+0x35d/0x870 mm/page-writeback.c:2683 __writeback_single_inode+0x14f/0x10d0 fs/fs-writeback.c:1658 writeback_sb_inodes+0x80c/0x1370 fs/fs-writeback.c:1954 __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:2025 wb_writeback+0x42f/0xbd0 fs/fs-writeback.c:2136 wb_check_background_flush fs/fs-writeback.c:2206 [inline] wb_do_writeback fs/fs-writeback.c:2294 [inline] wb_workfn+0xc58/0x1090 fs/fs-writeback.c:2321 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 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 INFO: task syz.0.1:5351 blocked for more than 144 seconds. Not tainted 6.11.0-syzkaller-11558-g075dbe9f6e3c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.1 state:D stack:23872 pid:5351 tgid:5321 ppid:5229 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1843/0x4ae0 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 io_schedule+0x8d/0x110 kernel/sched/core.c:7552 folio_wait_bit_common+0x882/0x12b0 mm/filemap.c:1309 folio_wait_writeback+0xe7/0x1e0 mm/page-writeback.c:3189 folio_prepare_writeback mm/page-writeback.c:2455 [inline] writeback_get_folio mm/page-writeback.c:2497 [inline] writeback_iter+0xb18/0x18d0 mm/page-writeback.c:2590 write_cache_pages+0x14d/0x230 mm/page-writeback.c:2639 bch2_writepages+0x14f/0x380 fs/bcachefs/fs-io-buffered.c:639 do_writepages+0x35d/0x870 mm/page-writeback.c:2683 filemap_fdatawrite_wbc+0x125/0x180 mm/filemap.c:398 __filemap_fdatawrite_range mm/filemap.c:431 [inline] file_write_and_wait_range+0x195/0x280 mm/filemap.c:788 bch2_fsync+0x13a/0x360 fs/bcachefs/fs-io.c:199 generic_write_sync include/linux/fs.h:2871 [inline] bch2_write_iter+0x21d9/0x23f0 fs/bcachefs/fs-io-buffered.c:1055 iter_file_splice_write+0xbfa/0x1510 fs/splice.c:743 do_splice_from fs/splice.c:941 [inline] direct_splice_actor+0x11b/0x220 fs/splice.c:1164 splice_direct_to_actor+0x586/0xc80 fs/splice.c:1108 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0x289/0x3e0 fs/splice.c:1233 do_sendfile+0x561/0xe10 fs/read_write.c:1388 __do_sys_sendfile64 fs/read_write.c:1455 [inline] __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1441 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: 0033:0x7fdfcc37df39 RSP: 002b:00007fdfcbdff038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007fdfcc536058 RCX: 00007fdfcc37df39 RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000006 RBP: 00007fdfcc3f0216 R08: 0000000000000000 R09: 0000000000000000 R10: 000000007a680000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fdfcc536058 R15: 00007fff239227e8 Showing all locks held in the system: 3 locks held by kworker/u8:0/11: #0: ffff88814ba09148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88814ba09148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000107d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000107d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcbe808 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4196 1 lock held by khungtaskd/30: #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6701 5 locks held by kworker/u8:2/35: #0: ffff88801baeb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801baeb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000ab7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000ab7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcb1d10 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580 #3: ffffffff8fcbe808 (rtnl_mutex){+.+.}-{3:3}, at: cleanup_net+0x6af/0xcc0 net/core/net_namespace.c:616 #4: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #4: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 3 locks held by kworker/u8:3/51: #0: ffff8881416e2948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff8881416e2948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000bb7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000bb7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffff88805a0100e0 (&type->s_umount_key#74){.+.+}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562 3 locks held by kworker/u8:4/67: #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: ffffc900015b7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900015b7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcbe808 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 1 lock held by dhcpcd/4888: #0: ffffffff8fcbe808 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1aa0 net/ipv4/devinet.c:1097 2 locks held by getty/4973: #0: ffff88814bc4e0a0 (&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/1:7/5270: #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90003f67d00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90003f67d00 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcbe808 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 1 lock held by syz.0.1/5322: #0: ffff88805a010420 (sb_writers#16){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline] #0: ffff88805a010420 (sb_writers#16){.+.+}-{0:0}, at: vfs_writev+0x2d1/0xba0 fs/read_write.c:1062 1 lock held by syz.0.1/5351: #0: ffff88805a010420 (sb_writers#16){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x220 fs/splice.c:1163 3 locks held by kworker/0:6/5334: 2 locks held by bch-copygc/loop/5340: 3 locks held by syz.0.98/6052: #0: ffff88805a0100e0 (&type->s_umount_key#74){.+.+}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805a0100e0 (&type->s_umount_key#74){.+.+}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff88805d104398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:151 [inline] #1: ffff88805d104398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:250 [inline] #1: ffff88805d104398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7de/0xd20 fs/bcachefs/btree_iter.c:3215 #2: ffff88805d1266d0 (&c->gc_lock){.+.+}-{3:3}, at: bch2_btree_update_start+0x682/0x14e0 fs/bcachefs/btree_update_interior.c:1202 3 locks held by syz-executor/6247: #0: ffff888061e0cd80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff888061e0cd80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2698 #1: ffff888061e0c078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x572/0x11a0 net/bluetooth/hci_sync.c:5183 #2: ffffffff8fe2b068 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1972 [inline] #2: ffffffff8fe2b068 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2589 2 locks held by syz.4.134/6399: #0: ffff88805a0100e0 (&type->s_umount_key#74){.+.+}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805a0100e0 (&type->s_umount_key#74){.+.+}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff88805a0127d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:388 [inline] #1: ffff88805a0127d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x26e/0xb50 fs/fs-writeback.c:2797 3 locks held by syz-executor/6498: #0: ffffffff8fd24570 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8fd24428 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:35 [inline] #1: ffffffff8fd24428 (genl_mutex){+.+.}-{3:3}, at: genl_op_lock net/netlink/genetlink.c:60 [inline] #1: ffffffff8fd24428 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x121/0xec0 net/netlink/genetlink.c:1209 #2: ffffffff8fcbe808 (rtnl_mutex){+.+.}-{3:3}, at: ieee80211_register_hw+0x312b/0x3e10 net/mac80211/main.c:1584 1 lock held by syz-executor/6588: #0: ffffffff8fcbe808 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcbe808 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 3 locks held by syz.3.177/6602: #0: ffff88805314cd80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff88805314cd80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2698 #1: ffff88805314c078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x572/0x11a0 net/bluetooth/hci_sync.c:5183 #2: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #2: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 3 locks held by syz.2.183/6627: #0: ffff88807e584d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff88807e584d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2698 #1: ffff88807e584078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x572/0x11a0 net/bluetooth/hci_sync.c:5183 #2: ffffffff8fe2b068 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1972 [inline] #2: ffffffff8fe2b068 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2589 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-11558-g075dbe9f6e3c #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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5340 Comm: bch-copygc/loop Not tainted 6.11.0-syzkaller-11558-g075dbe9f6e3c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__kasan_check_write+0x4/0x20 mm/kasan/shadow.c:37 Code: 31 d2 e9 6f e6 ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <89> f6 48 8b 0c 24 ba 01 00 00 00 e9 3c e6 ff ff 66 2e 0f 1f 84 00 RSP: 0018:ffffc900041a6a58 EFLAGS: 00000256 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff8bc4dbf5 RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffc900041a6b00 RBP: ffffc900041a6b70 R08: ffff88805d104617 R09: 1ffff1100ba208c2 R10: dffffc0000000000 R11: ffffed100ba208c3 R12: 1ffff92000834d60 R13: dffffc0000000000 R14: ffff88805d104610 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555571e8b808 CR3: 000000000e734000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_long_try_cmpxchg_release include/linux/atomic/atomic-instrumented.h:4480 [inline] __mutex_unlock_slowpath+0x21d/0x750 kernel/locking/mutex.c:929 bch2_btree_write_buffer_flush_locked+0x180/0x59f0 fs/bcachefs/btree_write_buffer.c:285 bch2_btree_write_buffer_flush_nocheck_rw fs/bcachefs/btree_write_buffer.c:544 [inline] bch2_btree_write_buffer_tryflush+0x16a/0x1c0 fs/bcachefs/btree_write_buffer.c:558 bch2_evacuate_bucket+0xe30/0x34e0 fs/bcachefs/move.c:697 bch2_copygc+0x3a03/0x4650 fs/bcachefs/movinggc.c:234 bch2_copygc_thread+0x737/0xc20 fs/bcachefs/movinggc.c:375 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