INFO: task kworker/u8:4:61 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-10622-gaa486552a110 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:4 state:D stack:20920 pid:61 tgid:61 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-bcachefs-2) 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.3.4:5353 blocked for more than 145 seconds. Not tainted 6.11.0-syzkaller-10622-gaa486552a110 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.4 state:D stack:26160 pid:5353 tgid:5300 ppid:5221 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+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 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 new_sync_write fs/read_write.c:590 [inline] vfs_write+0xa6d/0xc90 fs/read_write.c:683 ksys_pwrite64 fs/read_write.c:798 [inline] __do_sys_pwrite64 fs/read_write.c:808 [inline] __se_sys_pwrite64 fs/read_write.c:805 [inline] __x64_sys_pwrite64+0x1aa/0x230 fs/read_write.c:805 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: 0033:0x7f909417df39 RSP: 002b:00007f9094fdb038 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007f9094336058 RCX: 00007f909417df39 RDX: 0000000000000001 RSI: 0000000020000140 RDI: 000000000000000b RBP: 00007f90941f0216 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000f896 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f9094336058 R15: 00007ffe4d45f738 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937ee0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937ee0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937ee0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6701 3 locks held by kworker/u8:3/52: #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: ffffc90000bd7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000bd7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcbf408 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 3 locks held by kworker/u8:4/61: #0: ffff88801e2ca948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801e2ca948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc900015c7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900015c7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffff888027c340e0 (&type->s_umount_key#58){++++}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562 5 locks held by kworker/u8:9/3048: #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: ffffc90009e8fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90009e8fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcb2910 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580 #3: ffffffff8fcbf408 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xe9/0xaa0 net/core/dev.c:11930 #4: ffffffff8e93d478 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #4: ffffffff8e93d478 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 1 lock held by dhcpcd/4886: #0: ffffffff8fcbf408 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1aa0 net/ipv4/devinet.c:1097 2 locks held by getty/4976: #0: ffff88802e74e0a0 (&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 2 locks held by syz-executor/5214: #0: ffff8880310e80e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff8880310e80e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff8880310e80e0 (&type->s_umount_key#58){++++}-{3:3}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffff888055200278 (&c->state_lock){+.+.}-{3:3}, at: __bch2_fs_stop+0xfd/0x540 fs/bcachefs/super.c:618 1 lock held by syz.3.4/5301: #0: ffff888027c34420 (sb_writers#15){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline] #0: ffff888027c34420 (sb_writers#15){.+.+}-{0:0}, at: vfs_write+0x224/0xc90 fs/read_write.c:679 1 lock held by syz.3.4/5353: #0: ffff888027c34420 (sb_writers#15){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline] #0: ffff888027c34420 (sb_writers#15){.+.+}-{0:0}, at: vfs_write+0x224/0xc90 fs/read_write.c:679 2 locks held by bch-copygc/loop/5333: 3 locks held by bch-reclaim/loo/5391: 1 lock held by syz-executor/5689: #0: ffffffff8e93d478 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #0: ffffffff8e93d478 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976 1 lock held by syz-executor/6063: #0: ffffffff8fcbf408 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcbf408 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6121: #0: ffffffff8fcbf408 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcbf408 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6125: #0: ffffffff8fcbf408 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcbf408 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-10622-gaa486552a110 #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: 5333 Comm: bch-copygc/loop Not tainted 6.11.0-syzkaller-10622-gaa486552a110 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:instrument_atomic_read include/linux/instrumented.h:68 [inline] RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] RIP: 0010:btree_trans_verify_sorted_refs+0x387/0x560 fs/bcachefs/btree_iter.c:2760 Code: 00 00 00 44 0f b7 7d 00 48 8b 44 24 28 42 80 3c 28 00 74 08 4c 89 f7 e8 e7 ad e3 fd 4d 8b 36 4c 89 f8 48 c1 e8 06 49 8d 3c c6 08 00 00 00 e8 3f b0 e3 fd 31 ed 4d 0f a3 3e 41 0f 92 c6 40 0f RSP: 0018:ffffc90004646530 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff888078fe4018 RCX: ffff88807a361e00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888078fe41b8 RBP: ffff888078fe63ca R08: ffffffff84179178 R09: 1ffff1100f1fc837 R10: dffffc0000000000 R11: ffffed100f1fc838 R12: 0000000000000001 R13: dffffc0000000000 R14: ffff888078fe41b8 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f06d97c8f70 CR3: 0000000024e36000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: btree_path_list_add fs/bcachefs/btree_iter.c:2866 [inline] btree_path_alloc+0x7f7/0xa60 fs/bcachefs/btree_iter.c:1691 btree_path_clone fs/bcachefs/btree_iter.c:1229 [inline] __bch2_btree_path_make_mut+0x196/0x6c0 fs/bcachefs/btree_iter.c:1244 bch2_btree_path_make_mut fs/bcachefs/btree_iter.h:214 [inline] __bch2_btree_path_set_pos+0x382/0x1710 fs/bcachefs/btree_iter.c:1262 bch2_btree_path_set_pos fs/bcachefs/btree_iter.h:229 [inline] bch2_btree_iter_peek_upto+0x533d/0x6f00 fs/bcachefs/btree_iter.c:2394 bch2_btree_iter_peek_upto_type fs/bcachefs/btree_iter.h:685 [inline] bch2_get_next_backpointer+0x8bb/0x1320 fs/bcachefs/backpointers.c:246 bch2_evacuate_bucket+0x1075/0x34e0 fs/bcachefs/move.c:708 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