INFO: task syz-executor:6148 blocked for more than 143 seconds. Not tainted 6.15.0-rc6-syzkaller-00047-ge9565e23cd89 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:17576 pid:6148 tgid:6148 ppid:1 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:148 kthread_stop+0x194/0x5f0 kernel/kthread.c:791 bch2_copygc_stop+0x4f/0x150 fs/bcachefs/movinggc.c:435 __bch2_fs_read_only+0x47/0x4b0 fs/bcachefs/super.c:259 bch2_fs_read_only+0xd34/0x14c0 fs/bcachefs/super.c:352 __bch2_fs_stop+0x106/0x5a0 fs/bcachefs/super.c:628 generic_shutdown_super+0x135/0x2c0 fs/super.c:642 bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2620 deactivate_locked_super+0xb9/0x130 fs/super.c:473 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1431 task_work_run+0x1d1/0x260 kernel/task_work.c:227 resume_user_mode_work+0x5e/0x80 include/linux/resume_user_mode.h:50 exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x9a/0x120 kernel/entry/common.c:218 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa43e58fc97 RSP: 002b:00007fffaf1768b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fa43e61089d RCX: 00007fa43e58fc97 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fffaf176970 RBP: 00007fffaf176970 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fffaf177a00 R13: 00007fa43e61089d R14: 0000000000042fd8 R15: 00007fffaf177a40 INFO: task bch-reclaim/loo:11328 blocked for more than 144 seconds. Not tainted 6.15.0-rc6-syzkaller-00047-ge9565e23cd89 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:bch-reclaim/loo state:D stack:26856 pid:11328 tgid:11328 ppid:2 task_flags:0x200840 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746 btree_write_buffer_flush_seq+0x1829/0x19a0 fs/bcachefs/btree_write_buffer.c:569 bch2_btree_write_buffer_journal_flush+0x69/0xb0 fs/bcachefs/btree_write_buffer.c:586 journal_flush_pins+0x8e0/0xe90 fs/bcachefs/journal_reclaim.c:593 __bch2_journal_reclaim+0x781/0xd10 fs/bcachefs/journal_reclaim.c:724 bch2_journal_reclaim_thread+0x177/0x4f0 fs/bcachefs/journal_reclaim.c:766 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 3 locks held by kworker/u8:1/13: 1 lock held by khungtaskd/31: #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 3 locks held by kworker/0:2/975: 2 locks held by getty/5579: #0: ffff8880302df0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036cb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by kworker/0:3/5825: #0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000478fc60 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000478fc60 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #2: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998 2 locks held by syz-executor/6148: #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505 #1: ffff88805ce00278 (&c->state_lock){++++}-{4:4}, at: __bch2_fs_stop+0xfe/0x5a0 fs/bcachefs/super.c:627 3 locks held by bch-reclaim/loo/11328: #0: ffff88805ce4ad28 (&j->reclaim_lock){+.+.}-{4:4}, at: bch2_journal_reclaim_thread+0x16b/0x4f0 fs/bcachefs/journal_reclaim.c:765 #1: ffff88805ce04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #1: ffff88805ce04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #1: ffff88805ce04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x806/0xda0 fs/bcachefs/btree_iter.c:3385 #2: ffff88805ce045d0 (&wb->flushing.lock){+.+.}-{4:4}, at: btree_write_buffer_flush_seq+0x1829/0x19a0 fs/bcachefs/btree_write_buffer.c:569 3 locks held by bch-copygc/loop/11329: #0: ffff88805ce04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #0: ffff88805ce04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #0: ffff88805ce04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3202 #1: ffff88805ce045d0 (&wb->flushing.lock){+.+.}-{4:4}, at: btree_write_buffer_flush_seq+0x1829/0x19a0 fs/bcachefs/btree_write_buffer.c:569 #2: ffff88805ce26590 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x68f/0x14c0 fs/bcachefs/btree_update_interior.c:1179 1 lock held by syz.9.420/14388: #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz.9.420/14391: #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz.9.420/14392: #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz.9.420/14393: #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz.9.420/14396: #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz.9.420/14398: #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz.9.420/14401: #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz.9.420/14404: #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz-executor/16537: #0: ffffffff8f2e5008 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:633 [inline] #0: ffffffff8f2e5008 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3390 5 locks held by syz-executor/16791: #0: ffff888067e40d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff888067e40d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x1fe/0x500 net/bluetooth/hci_core.c:2678 #1: ffff888067e40078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5213 #2: ffffffff8f44a9c8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2064 [inline] #2: ffffffff8f44a9c8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 net/bluetooth/hci_conn.c:2534 #3: ffff888057396338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 net/bluetooth/l2cap_core.c:1761 #4: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #4: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998 1 lock held by syz.0.517/16861: #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 2 locks held by syz.7.522/17046: #0: ffff888011d96420 (sb_writers#3){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1157 #1: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #1: ffff88805cd380e0 (&type->s_umount_key#73){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 4 locks held by syz.3.525/17339: 2 locks held by syz.3.525/17385: #0: ffff888030e46420 (sb_writers#28){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556 #1: ffff8880562e2a58 (&type->i_mutex_dir_key#18/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline] #1: ffff8880562e2a58 (&type->i_mutex_dir_key#18/1){+.+.}-{4:4}, at: filename_create+0x1f9/0x470 fs/namei.c:4132 2 locks held by syz.3.525/17386: #0: ffff888030e46420 (sb_writers#28){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556 #1: ffff8880562e2a58 (&type->i_mutex_dir_key#18){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff8880562e2a58 (&type->i_mutex_dir_key#18){++++}-{4:4}, at: open_last_lookups fs/namei.c:3797 [inline] #1: ffff8880562e2a58 (&type->i_mutex_dir_key#18){++++}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4036 2 locks held by syz.3.525/17387: #0: ffff888030e46420 (sb_writers#28){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556 #1: ffff8880562e2a58 (&type->i_mutex_dir_key#18/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline] #1: ffff8880562e2a58 (&type->i_mutex_dir_key#18/1){+.+.}-{4:4}, at: lock_rename fs/namei.c:3265 [inline] #1: ffff8880562e2a58 (&type->i_mutex_dir_key#18/1){+.+.}-{4:4}, at: do_renameat2+0x3dd/0xc50 fs/namei.c:5216 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-00047-ge9565e23cd89 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 15102 Comm: kworker/u8:10 Not tainted 6.15.0-rc6-syzkaller-00047-ge9565e23cd89 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:check_preemption_disabled+0x17/0x120 lib/smp_processor_id.c:14 Code: 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 48 83 ec 10 65 48 8b 05 4e fe 22 07 48 89 44 24 08 <65> 8b 05 56 fe 22 07 65 8b 0d 4b fe 22 07 f7 c1 ff ff ff 7f 74 23 RSP: 0018:ffffc90003d7f988 EFLAGS: 00000286 RAX: 524273c349592900 RBX: ffff88802df40000 RCX: ffff888062361e00 RDX: 0000000000000000 RSI: ffffffff8bc104c0 RDI: ffffffff8bc10480 RBP: ffff8880319751e0 R08: ffff888062361e00 R09: 0000000000000002 R10: 0000000000000001 R11: 0000000000000000 R12: dffffc0000000000 R13: ffff88802df40000 R14: ffff88801da808c0 R15: ffffffff86f9568f FS: 0000000000000000(0000) GS:ffff8881260fb000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005584d43ba9f8 CR3: 000000007a4d6000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:736 trace_kmem_cache_free include/trace/events/kmem.h:114 [inline] kmem_cache_free+0x5e/0x3f0 mm/slub.c:4743 nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline] nsim_dev_trap_report_work+0x7cf/0xb80 drivers/net/netdevsim/dev.c:851 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245