INFO: task syz.1.56:6472 blocked for more than 143 seconds. Not tainted 6.15.0-rc3-syzkaller-00342-g5bc1018675ec #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.56 state:D stack:26088 pid:6472 tgid:6387 ppid:5830 task_flags:0x400040 flags:0x00000004 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 rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write_nested+0x1b5/0x200 kernel/locking/rwsem.c:1694 inode_lock_nested include/linux/fs.h:902 [inline] do_unlinkat+0x1bf/0x560 fs/namei.c:4630 __do_sys_unlink fs/namei.c:4689 [inline] __se_sys_unlink fs/namei.c:4687 [inline] __x64_sys_unlink+0x47/0x50 fs/namei.c:4687 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb53178e969 RSP: 002b:00007fb532510038 EFLAGS: 00000246 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 00007fb5319b6080 RCX: 00007fb53178e969 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000080 RBP: 00007fb531810ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fb5319b6080 R15: 00007ffdd535dc68 INFO: task syz.1.56:6488 blocked for more than 144 seconds. Not tainted 6.15.0-rc3-syzkaller-00342-g5bc1018675ec #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.56 state:D stack:28776 pid:6488 tgid:6387 ppid:5830 task_flags:0x400040 flags:0x00000004 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 rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1578 inode_lock include/linux/fs.h:867 [inline] open_last_lookups fs/namei.c:3797 [inline] path_openat+0x8da/0x3830 fs/namei.c:4036 do_filp_open+0x1fa/0x410 fs/namei.c:4066 do_sys_openat2+0x121/0x1c0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_open fs/open.c:1452 [inline] __se_sys_open fs/open.c:1448 [inline] __x64_sys_open+0x11e/0x150 fs/open.c:1448 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb53178e969 RSP: 002b:00007fb52f5f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007fb5319b6160 RCX: 00007fb53178e969 RDX: 0000000000000000 RSI: 0000000000109042 RDI: 0000200000000000 RBP: 00007fb531810ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fb5319b6160 R15: 00007ffdd535dc68 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: #0: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #0: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998 2 locks held by kworker/u8:1/13: #0: ffff8880b89399d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605 #1: ffff8880b8923b08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987 1 lock held by khungtaskd/31: #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 5 locks held by kworker/u8:2/36: #0: ffff88801aef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801aef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 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+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8f2d49d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x145/0xbd0 net/core/net_namespace.c:608 #3: ffffffff8f2e1508 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xdc/0x890 net/core/dev.c:12524 #4: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #4: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998 3 locks held by kworker/u8:5/1137: #0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc90003cffc60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003cffc60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8f2e1508 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 1 lock held by dhcpcd/5485: #0: ffffffff8f2e1508 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f2e1508 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x323/0x1b50 net/ipv4/devinet.c:1121 2 locks held by getty/5573: #0: ffff8880331000a0 (&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 5 locks held by syz.1.56/6388: #0: ffff88807abb4420 (sb_writers#22){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556 #1: ffff8880336a1810 (&sb->s_type->i_mutex_key#28){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff8880336a1810 (&sb->s_type->i_mutex_key#28){++++}-{4:4}, at: open_last_lookups fs/namei.c:3797 [inline] #1: ffff8880336a1810 (&sb->s_type->i_mutex_key#28){++++}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4036 #2: ffff8880336a1bf8 (&inode->ei_update_lock){+.+.}-{4:4}, at: __bch2_create+0x2f2/0xb90 fs/bcachefs/fs.c:567 #3: ffff888077004228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #3: ffff888077004228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #3: ffff888077004228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3202 #4: ffff888077026590 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x68f/0x14c0 fs/bcachefs/btree_update_interior.c:1179 2 locks held by syz.1.56/6472: #0: ffff88807abb4420 (sb_writers#22){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556 #1: ffff8880336a1810 (&sb->s_type->i_mutex_key#28/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline] #1: ffff8880336a1810 (&sb->s_type->i_mutex_key#28/1){+.+.}-{4:4}, at: do_unlinkat+0x1bf/0x560 fs/namei.c:4630 2 locks held by syz.1.56/6488: #0: ffff88807abb4420 (sb_writers#22){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556 #1: ffff8880336a1810 (&sb->s_type->i_mutex_key#28){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff8880336a1810 (&sb->s_type->i_mutex_key#28){++++}-{4:4}, at: open_last_lookups fs/namei.c:3797 [inline] #1: ffff8880336a1810 (&sb->s_type->i_mutex_key#28){++++}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4036 6 locks held by bch-copygc/loop/6452: 2 locks held by syz-executor/8915: #0: ffffffff8f7de650 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8f7de650 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8f7de650 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8f2e1508 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f2e1508 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8f2e1508 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4064 2 locks held by syz.2.327/9064: 2 locks held by syz.9.328/9071: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc3-syzkaller-00342-g5bc1018675ec #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 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: 6452 Comm: bch-copygc/loop Not tainted 6.15.0-rc3-syzkaller-00342-g5bc1018675ec #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210 Code: 89 fb e8 23 00 00 00 48 8b 3d 6c c6 d5 0b 48 89 de 5b e9 33 3d 55 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 e0 71 92 65 8b 15 38 22 RSP: 0018:ffffc90003e7e9e8 EFLAGS: 00000246 RAX: ffffffff841df7e7 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88802f979e00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffc90003e7e8e7 R09: 0000000000000000 R10: ffffc90003e7e8c0 R11: fffff520007cfd1d R12: 00000000ffffffff R13: ffff888053ab82b8 R14: 1ffff1100a757057 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888126102000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4e0efff000 CR3: 000000007ef92000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: bch2_btree_path_verify_locks+0x718/0xba0 fs/bcachefs/btree_locking.c:872 bch2_btree_path_traverse_one+0x1b4f/0x2430 fs/bcachefs/btree_iter.c:1224 bch2_btree_path_traverse fs/bcachefs/btree_iter.h:248 [inline] __bch2_btree_iter_peek fs/bcachefs/btree_iter.c:2243 [inline] bch2_btree_iter_peek_max+0x988/0x5260 fs/bcachefs/btree_iter.c:2347 bch2_btree_iter_peek fs/bcachefs/btree_iter.h:409 [inline] __bch2_move_data_phys+0xa31/0x1b10 fs/bcachefs/move.c:797 bch2_evacuate_bucket+0x1b8/0x2b0 fs/bcachefs/move.c:946 bch2_copygc+0x323b/0x3cf0 fs/bcachefs/movinggc.c:240 bch2_copygc_thread+0x8c9/0xd40 fs/bcachefs/movinggc.c:405 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