INFO: task syz.0.1:5332 blocked for more than 149 seconds. Not tainted 6.11.0-next-20240926-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.1 state:D stack:23904 pid:5332 tgid:5315 ppid:5233 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 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:1310 folio_wait_writeback+0xe7/0x1e0 mm/page-writeback.c:3189 truncate_inode_pages_range+0xafd/0xfc0 mm/truncate.c:398 bchfs_fallocate+0x2d1/0x730 fs/bcachefs/fs-io.c:718 bch2_fallocate_dispatch+0x3ac/0x540 fs/bcachefs/fs-io.c:771 vfs_fallocate+0x623/0x7a0 fs/open.c:333 do_vfs_ioctl+0x2583/0x2e40 fs/ioctl.c:886 __do_sys_ioctl fs/ioctl.c:905 [inline] __se_sys_ioctl+0x81/0x170 fs/ioctl.c:893 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: 0033:0x7fb7eef7df39 RSP: 002b:00007fb7efdf4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fb7ef136058 RCX: 00007fb7eef7df39 RDX: 0000000020000180 RSI: 0000000040305839 RDI: 0000000000000008 RBP: 00007fb7eeff0216 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fb7ef136058 R15: 00007ffc98626438 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937f20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937f20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937f20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720 2 locks held by kworker/u8:2/35: #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: ffff8880b8728948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:989 4 locks held by kworker/u8:5/1307: #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc9000458fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000458fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcc8690 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580 #3: ffffffff8fcd5188 (rtnl_mutex){+.+.}-{3:3}, at: ieee80211_unregister_hw+0x55/0x2c0 net/mac80211/main.c:1662 2 locks held by kworker/u8:8/2938: #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: ffffc90009597d00 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90009597d00 ((reaper_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 2 locks held by kworker/u8:11/3083: #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: ffffc90009d87d00 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90009d87d00 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 1 lock held by dhcpcd/4902: #0: ffffffff8fcd5188 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1aa0 net/ipv4/devinet.c:1097 2 locks held by getty/4990: #0: ffff88802e89e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by kworker/0:3/5267: 1 lock held by syz.0.1/5316: #0: ffff88807bbca420 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2949 [inline] #0: ffff88807bbca420 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x224/0xc90 fs/read_write.c:679 2 locks held by syz.0.1/5332: #0: ffff88807bbca420 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2949 [inline] #0: ffff88807bbca420 (sb_writers#13){.+.+}-{0:0}, at: vfs_fallocate+0x59d/0x7a0 fs/open.c:332 #1: ffff88805cd688c0 (&sb->s_type->i_mutex_key#21){++++}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #1: ffff88805cd688c0 (&sb->s_type->i_mutex_key#21){++++}-{3:3}, at: bch2_fallocate_dispatch+0x1e2/0x540 fs/bcachefs/fs-io.c:762 3 locks held by bch-copygc/loop/5325: 2 locks held by syz-executor/5524: 2 locks held by syz-executor/6130: #0: ffffffff8fcd5188 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd5188 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 #1: ffffffff8e93d4b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #1: ffffffff8e93d4b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 1 lock held by syz.1.134/6194: #0: ffffffff8e93d4b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #0: ffffffff8e93d4b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976 1 lock held by syz.3.135/6196: #0: ffffffff8fcd5188 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x86e/0x1340 net/core/dev_ioctl.c:807 1 lock held by syz.4.139/6207: #0: ffffffff8fcd5188 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x48c/0x2400 drivers/net/tun.c:3121 1 lock held by syz.4.139/6209: #0: ffffffff8fcd5188 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x48c/0x2400 drivers/net/tun.c:3121 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-next-20240926-syzkaller #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: 5325 Comm: bch-copygc/loop Not tainted 6.11.0-next-20240926-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__bch2_btree_path_set_pos+0x36e/0x1710 fs/bcachefs/btree_iter.c:1262 Code: e8 57 d1 7b fd 83 e3 40 75 16 e8 ad cd 7b fd eb 35 85 db 0f 84 97 13 00 00 e8 9e cd 7b fd eb 05 e8 97 cd 7b fd 48 8b 4c 24 30 <8b> 44 24 18 0f b6 d0 48 8b 7c 24 48 44 89 fe e8 ae f5 ff ff 89 44 RSP: 0018:ffffc900043066c0 EFLAGS: 00000293 RAX: ffffffff84191559 RBX: 0000000000000040 RCX: ffffffff840fbeb5 RDX: 0000000000000000 RSI: 0000000000000040 RDI: 0000000000000000 RBP: ffffc900043067f8 R08: ffffffff84191539 R09: ffffffff841914fe R10: 0000000000000002 R11: ffff888027931e00 R12: ffff88807ed341c8 R13: ffff88807ed34010 R14: 1ffff1100fda6802 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff87d46fc0 CR3: 000000000e734000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: bch2_btree_path_set_pos fs/bcachefs/btree_iter.h:231 [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:687 [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