INFO: task syz.2.25:5459 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-10045-g97d8894b6f4c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.25 state:D stack:24352 pid:5459 tgid:5422 ppid:5227 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 io_schedule+0x8d/0x110 kernel/sched/core.c:7551 folio_wait_bit_common+0x882/0x12b0 mm/filemap.c:1309 folio_wait_writeback+0xe7/0x1e0 mm/page-writeback.c:3189 truncate_inode_pages_range+0xafd/0xfc0 mm/truncate.c:398 truncate_inode_pages mm/truncate.c:423 [inline] truncate_pagecache mm/truncate.c:727 [inline] truncate_setsize+0xcf/0xf0 mm/truncate.c:752 bchfs_truncate+0x6df/0xc70 fs/bcachefs/fs-io.c:441 notify_change+0xbca/0xe90 fs/attr.c:503 do_truncate+0x220/0x310 fs/open.c:65 handle_truncate fs/namei.c:3395 [inline] do_open fs/namei.c:3778 [inline] path_openat+0x2e1e/0x3590 fs/namei.c:3933 do_filp_open+0x235/0x490 fs/namei.c:3960 do_sys_openat2+0x13e/0x1d0 fs/open.c:1415 do_sys_open fs/open.c:1430 [inline] __do_sys_creat fs/open.c:1506 [inline] __se_sys_creat fs/open.c:1500 [inline] __x64_sys_creat+0x123/0x170 fs/open.c:1500 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: 0033:0x7fa5cbd7def9 RSP: 002b:00007fa5ccb1b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 00007fa5cbf36058 RCX: 00007fa5cbd7def9 RDX: 0000000000000000 RSI: 0000000000000105 RDI: 0000000020004b40 RBP: 00007fa5cbdf0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fa5cbf36058 R15: 00007ffff91c5558 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 5 locks held by kworker/u8:3/52: #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: ffffc90000bd7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000bd7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcaec50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580 #3: ffffffff8fcbb748 (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 3 locks held by kworker/u8:4/62: #0: ffff8880b863ea58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:593 #1: ffffc900015e7d00 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900015e7d00 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffff8880b862a718 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x112/0x240 kernel/time/timer.c:1051 3 locks held by kworker/u8:7/2937: #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: ffffc900092a7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900092a7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcbb748 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 1 lock held by dhcpcd/4885: #0: ffffffff8fcbb748 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1aa0 net/ipv4/devinet.c:1097 2 locks held by getty/4977: #0: ffff8880322120a0 (&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 1 lock held by syz.2.25/5423: #0: ffff88806cdaa420 (sb_writers#22){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2930 [inline] #0: ffff88806cdaa420 (sb_writers#22){.+.+}-{0:0}, at: vfs_writev+0x2d1/0xba0 fs/read_write.c:1062 2 locks held by syz.2.25/5459: #0: ffff88806cdaa420 (sb_writers#22){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 #1: ffff88805d900148 (&sb->s_type->i_mutex_key#28){++++}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #1: ffff88805d900148 (&sb->s_type->i_mutex_key#28){++++}-{3:3}, at: do_truncate+0x20c/0x310 fs/open.c:63 1 lock held by syz-executor/6518: #0: ffffffff8fcbb748 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fcbb748 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 2 locks held by syz.4.195/6740: #0: ffff88806cdaa0e0 (&type->s_umount_key#103){.+.+}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88806cdaa0e0 (&type->s_umount_key#103){.+.+}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff88806cdaa938 (&s->s_sync_lock){+.+.}-{3:3}, at: wait_sb_inodes fs/fs-writeback.c:2619 [inline] #1: ffff88806cdaa938 (&s->s_sync_lock){+.+.}-{3:3}, at: sync_inodes_sb+0x32e/0xb50 fs/fs-writeback.c:2802 2 locks held by syz.1.201/6829: #0: ffff88806cdaa0e0 (&type->s_umount_key#103){.+.+}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88806cdaa0e0 (&type->s_umount_key#103){.+.+}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff88806cdaa938 (&s->s_sync_lock){+.+.}-{3:3}, at: wait_sb_inodes fs/fs-writeback.c:2619 [inline] #1: ffff88806cdaa938 (&s->s_sync_lock){+.+.}-{3:3}, at: sync_inodes_sb+0x32e/0xb50 fs/fs-writeback.c:2802 1 lock held by syz-executor/7024: #0: ffffffff8fcbb748 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fcbb748 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 1 lock held by syz-executor/7450: #0: ffffffff8fcbb748 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcbb748 (rtnl_mutex){+.+.}-{3:3}, at: __rtnl_newlink net/core/rtnetlink.c:3720 [inline] #0: ffffffff8fcbb748 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_newlink+0xab7/0x20a0 net/core/rtnetlink.c:3743 3 locks held by syz.1.352/7636: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-10045-g97d8894b6f4c #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: 7636 Comm: syz.1.352 Not tainted 6.11.0-syzkaller-10045-g97d8894b6f4c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0033:0x7f8594241cd8 Code: 85 ed 74 33 66 0f 1f 44 00 00 48 39 f0 72 1b 4d 8b 07 49 89 c1 49 29 f1 47 0f b6 0c 08 45 84 c9 74 08 45 88 0c 00 49 8b 47 10 <48> 83 c0 01 49 89 47 10 83 e9 01 73 d3 41 81 fe 00 01 00 00 0f 85 RSP: 002b:00007f85952294a0 EFLAGS: 00000246 RAX: 00000000000c8222 RBX: 00007f8595229540 RCX: 000000000000004a RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00007f85952295e0 RBP: 0000000000000102 R08: 00007f8589a00000 R09: 0000000000000000 R10: 0000000000000000 R11: 00007f8595229550 R12: 0000000000000001 R13: 00007f8594404f00 R14: 0000000000000000 R15: 00007f85952295e0 FS: 00007f859522a6c0 GS: 0000000000000000