INFO: task syz.2.41:5700 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-08836-gf8eb5bd9a818 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.41 state:D stack:18912 pid:5700 tgid:5699 ppid:5451 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1843/0x4ae0 kernel/sched/core.c:6674 __schedule_loop kernel/sched/core.c:6751 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6766 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6823 rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1178 __down_write_common kernel/locking/rwsem.c:1306 [inline] __down_write kernel/locking/rwsem.c:1315 [inline] down_write+0x1d7/0x220 kernel/locking/rwsem.c:1580 inode_lock include/linux/fs.h:815 [inline] do_truncate fs/open.c:63 [inline] do_ftruncate+0x44e/0x580 fs/open.c:181 do_sys_ftruncate fs/open.c:199 [inline] __do_sys_ftruncate fs/open.c:207 [inline] __se_sys_ftruncate fs/open.c:205 [inline] __x64_sys_ftruncate+0x95/0xf0 fs/open.c:205 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: 0033:0x7fcca177def9 RSP: 002b:00007fcca262c038 EFLAGS: 00000246 ORIG_RAX: 000000000000004d RAX: ffffffffffffffda RBX: 00007fcca1935f80 RCX: 00007fcca177def9 RDX: 0000000000000000 RSI: 0000000000002ff8 RDI: 0000000000000004 RBP: 00007fcca17f0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fcca1935f80 R15: 00007fffe3c3b008 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/u8:2/35: #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: ffffc90000ab7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000ab7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcb97c8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 3 locks held by kworker/u8:3/52: #0: ffff88802da5f148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88802da5f148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000bd7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000bd7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcb97c8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4196 5 locks held by kworker/u8:7/2497: #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: ffffc90009027d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90009027d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcaccd0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580 #3: ffffffff8fcb97c8 (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:297 [inline] #4: ffffffff8e93d478 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976 1 lock held by klogd/4661: #0: ffff8880b863ea58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:593 2 locks held by dhcpcd/4886: #0: ffff88807a9256c8 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: __netlink_dump_start+0x119/0x790 net/netlink/af_netlink.c:2404 #1: ffffffff8fcb97c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #1: ffffffff8fcb97c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_dumpit+0x99/0x200 net/core/rtnetlink.c:6505 2 locks held by getty/4981: #0: ffff88802e1740a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002efe2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by syz.2.41/5700: #0: ffff88807aac8420 (sb_writers#22){.+.+}-{0:0}, at: do_ftruncate+0x28b/0x580 fs/open.c:178 #1: ffff8880777988a8 (&sb->s_type->i_mutex_key#29){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #1: ffff8880777988a8 (&sb->s_type->i_mutex_key#29){+.+.}-{3:3}, at: do_truncate fs/open.c:63 [inline] #1: ffff8880777988a8 (&sb->s_type->i_mutex_key#29){+.+.}-{3:3}, at: do_ftruncate+0x44e/0x580 fs/open.c:181 5 locks held by syz.2.41/5739: #0: ffff88807aac8420 (sb_writers#22){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 #1: ffff8880777988a8 (&sb->s_type->i_mutex_key#29){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #1: ffff8880777988a8 (&sb->s_type->i_mutex_key#29){+.+.}-{3:3}, at: do_truncate+0x20c/0x310 fs/open.c:63 #2: ffff88805b600a18 (&c->snapshot_create_lock){.+.+}-{3:3}, at: bch2_truncate+0x16c/0x2c0 fs/bcachefs/io_misc.c:290 #3: ffff88805b6042c0 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:151 [inline] #3: ffff88805b6042c0 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:250 [inline] #3: ffff88805b6042c0 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7de/0xd20 fs/bcachefs/btree_iter.c:3200 #4: ffff88805b626690 (&c->gc_lock){.+.+}-{3:3}, at: bch2_btree_update_start+0x682/0x14e0 fs/bcachefs/btree_update_interior.c:1197 2 locks held by bch-reclaim/loo/5725: 5 locks held by syz.1.77/6252: #0: ffff8880235146b0 (&bdev->bd_fsfreeze_mutex){+.+.}-{3:3}, at: bdev_freeze+0x2a/0x220 block/bdev.c:248 #1: ffff88806527a420 (sb_writers#21){++++}-{0:0}, at: sb_wait_write fs/super.c:1896 [inline] #1: ffff88806527a420 (sb_writers#21){++++}-{0:0}, at: freeze_super+0x4e9/0xee0 fs/super.c:2085 #2: ffff88806527a0e0 (&type->s_umount_key#77){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #2: ffff88806527a0e0 (&type->s_umount_key#77){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #2: ffff88806527a0e0 (&type->s_umount_key#77){++++}-{3:3}, at: freeze_super+0x4f1/0xee0 fs/super.c:2086 #3: ffff88806527a518 (sb_pagefaults#3){+.+.}-{0:0}, at: sb_wait_write fs/super.c:1896 [inline] #3: ffff88806527a518 (sb_pagefaults#3){+.+.}-{0:0}, at: freeze_super+0x519/0xee0 fs/super.c:2090 #4: ffff88806527a610 (sb_internal#4){++++}-{0:0}, at: sb_wait_write fs/super.c:1896 [inline] #4: ffff88806527a610 (sb_internal#4){++++}-{0:0}, at: freeze_super+0x7cc/0xee0 fs/super.c:2104 1 lock held by syz.1.224/6949: #0: ffff88806527a0e0 (&type->s_umount_key#77){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88806527a0e0 (&type->s_umount_key#77){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 1 lock held by syz-executor/6950: #0: ffffffff8fcb97c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcb97c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 2 locks held by syz-executor/6977: #0: ffffffff8fcaccd0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:490 #1: ffffffff8fcb97c8 (rtnl_mutex){+.+.}-{3:3}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3885 1 lock held by syz.2.230/6997: #0: ffff88806527a0e0 (&type->s_umount_key#77){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88806527a0e0 (&type->s_umount_key#77){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 1 lock held by syz-executor/7001: #0: ffffffff8fcb97c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcb97c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/7010: #0: ffffffff8fcb97c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcb97c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-08836-gf8eb5bd9a818 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5725 Comm: bch-reclaim/loo Not tainted 6.11.0-syzkaller-08836-gf8eb5bd9a818 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:get_current arch/x86/include/asm/current.h:49 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216 Code: 8b 3d d4 0e 9b 0c 48 89 de 5b e9 d3 a8 5a 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0c 25 80 d7 03 00 65 8b 15 f0 23 6f 7e 81 e2 00 01 ff 00 RSP: 0018:ffffc900031a7490 EFLAGS: 00000246 RAX: ffffffff84194853 RBX: 1ffff1100ad51008 RCX: ffff8880264f5a00 RDX: ffff8880264f5a00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffff84194849 R09: 1ffff1100b6c0035 R10: dffffc0000000000 R11: ffffed100b6c0036 R12: 0000000000000040 R13: 0000000000000040 R14: ffff888056a88042 R15: ffff888056a88000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3603a67d60 CR3: 000000000e734000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trans_set_unlocked fs/bcachefs/btree_locking.h:205 [inline] bch2_trans_unlock+0x333/0x470 fs/bcachefs/btree_locking.c:812 bch2_btree_write_buffer_flush_locked+0x156/0x59f0 fs/bcachefs/btree_write_buffer.c:280 btree_write_buffer_flush_seq+0x1a43/0x1bc0 fs/bcachefs/btree_write_buffer.c:510 bch2_btree_write_buffer_journal_flush+0x4e/0x80 fs/bcachefs/btree_write_buffer.c:525 journal_flush_pins+0x5f7/0xb20 fs/bcachefs/journal_reclaim.c:565 __bch2_journal_reclaim+0x77d/0xe40 fs/bcachefs/journal_reclaim.c:697 bch2_journal_reclaim_thread+0x174/0x560 fs/bcachefs/journal_reclaim.c:739 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