INFO: task bch-reclaim/loo:6037 blocked for more than 144 seconds. Not tainted 6.15.0-rc1-next-20250411-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:bch-reclaim/loo state:D stack:15272 pid:6037 tgid:6037 ppid:2 task_flags:0x200040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b9a/0x5250 kernel/sched/core.c:6769 __schedule_loop kernel/sched/core.c:6847 [inline] schedule+0x163/0x360 kernel/sched/core.c:6862 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6919 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x805/0x10c0 kernel/locking/mutex.c:746 bch2_journal_reclaim_thread+0x160/0x580 fs/bcachefs/journal_reclaim.c:761 kthread+0x7b7/0x940 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: 1 lock held by khungtaskd/31: #0: ffffffff8ed3f180 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ed3f180 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8ed3f180 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764 3 locks held by kworker/u8:2/36: #0: ffff88801bef6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801bef6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90000ad7c60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000ad7c60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff900f6710 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17c/0xd60 net/core/net_namespace.c:608 2 locks held by getty/5585: #0: ffff8880319090a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900033632f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222 6 locks held by syz-executor/5834: #0: ffff8880607480e0 (&type->s_umount_key#60){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff8880607480e0 (&type->s_umount_key#60){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff8880607480e0 (&type->s_umount_key#60){+.+.}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:506 #1: ffff88805e380278 (&c->state_lock){+.+.}-{4:4}, at: __bch2_fs_stop+0xff/0x5b0 fs/bcachefs/super.c:646 #2: ffff88805e3cad28 (&j->reclaim_lock){+.+.}-{4:4}, at: journal_flush_done+0x85/0x820 fs/bcachefs/journal_reclaim.c:872 #3: ffff88805e384218 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #3: ffff88805e384218 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #3: ffff88805e384218 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7ed/0xd40 fs/bcachefs/btree_iter.c:3419 #4: ffff88805e3845c0 (&wb->flushing.lock){+.+.}-{4:4}, at: btree_write_buffer_flush_seq+0x1aec/0x1ca0 fs/bcachefs/btree_write_buffer.c:569 #5: ffff88805e3a6590 (&c->gc_lock){.+.+}-{4:4}, at: bch2_btree_update_start+0x68a/0x16c0 fs/bcachefs/btree_update_interior.c:1179 3 locks held by kworker/u8:10/5977: #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc900049c7c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc900049c7c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff90103248 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 1 lock held by bch-reclaim/loo/6037: #0: ffff88805e3cad28 (&j->reclaim_lock){+.+.}-{4:4}, at: bch2_journal_reclaim_thread+0x160/0x580 fs/bcachefs/journal_reclaim.c:761 3 locks held by syz-executor/7372: #0: ffffffff8f896560 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8f896560 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8f896560 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:570 #1: ffffffff90103248 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff90103248 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff90103248 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xd68/0x1fe0 net/core/rtnetlink.c:4067 #2: ffffffff8ed446b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #2: ffffffff8ed446b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x454/0x830 kernel/rcu/tree_exp.h:998 2 locks held by syz-executor/7409: #0: ffffffff906088a0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff906088a0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff906088a0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:570 #1: ffffffff90103248 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff90103248 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff90103248 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xd68/0x1fe0 net/core/rtnetlink.c:4067 2 locks held by syz.3.248/7449: #0: ffff88807c956208 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:866 [inline] #0: ffff88807c956208 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline] #0: ffff88807c956208 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: sock_close+0x90/0x240 net/socket.c:1391 #1: ffffffff8ed446b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #1: ffffffff8ed446b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x384/0x830 kernel/rcu/tree_exp.h:998 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc1-next-20250411-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 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+0x1058/0x10a0 kernel/hung_task.c:437 kthread+0x7b7/0x940 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5883 Comm: kworker/1:4 Not tainted 6.15.0-rc1-next-20250411-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: rcu_gp process_srcu RIP: 0010:delay_tsc+0x5c/0xe0 arch/x86/lib/delay.c:79 Code: 90 48 89 d5 48 c1 e5 20 48 09 c5 48 29 dd 4c 39 f5 73 67 bf 01 00 00 00 e8 f1 c1 5e f5 65 8b 05 ea 15 38 07 85 c0 74 2f f3 90 01 00 00 00 e8 3a c0 5e f5 e8 a5 56 01 00 41 39 c7 75 20 0f 01 RSP: 0018:ffffc90004917988 EFLAGS: 00000286 RAX: 0000000080000000 RBX: 000000abe8be1423 RCX: 0000000000000001 RDX: 00000000000000ab RSI: ffffffff8ca1ee20 RDI: 0000000000000001 RBP: 0000000000002408 R08: ffff8880b8741787 R09: 1ffff110170e82f0 R10: dffffc0000000000 R11: ffffffff8c31e9f0 R12: 0000000000004515 R13: ffff8880b87417a0 R14: 0000000000002af9 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888125080000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9fb1979ab8 CR3: 0000000035534000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: udelay include/asm-generic/delay.h:64 [inline] try_check_zero+0x38a/0x3f0 kernel/rcu/srcutree.c:1116 srcu_advance_state kernel/rcu/srcutree.c:1752 [inline] process_srcu+0x36a/0x14b0 kernel/rcu/srcutree.c:1861 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd50 kernel/workqueue.c:3400 kthread+0x7b7/0x940 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