INFO: task syz.2.3:5339 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-11728-gad46e8f95e93 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.3 state:D stack:25904 pid:5339 tgid:5313 ppid:5228 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1843/0x4ae0 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752 fdget_pos+0x24e/0x320 fs/file.c:1187 ksys_write+0x7e/0x2b0 fs/read_write.c:727 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: 0033:0x7feb9ef7dff9 RSP: 002b:00007feb9e9de038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007feb9f136058 RCX: 00007feb9ef7dff9 RDX: 0000000000000118 RSI: 0000000020000280 RDI: 0000000000000005 RBP: 00007feb9eff0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007feb9f136058 R15: 00007ffe78fa94d8 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6701 3 locks held by kworker/u8:2/33: #0: ffff88814b8af148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88814b8af148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000a97d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000a97d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcbef48 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4196 2 locks held by getty/4988: #0: ffff88802e8470a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by kworker/0:3/5238: #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90003e2fd00 ((fqdir_free_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90003e2fd00 ((fqdir_free_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8e93d200 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:4561 2 locks held by syz.2.3/5314: #0: ffff88802cd59eb8 (&f->f_pos_lock){+.+.}-{3:3}, at: fdget_pos+0x24e/0x320 fs/file.c:1187 #1: ffff888059d52420 (sb_writers#16){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline] #1: ffff888059d52420 (sb_writers#16){.+.+}-{0:0}, at: vfs_write+0x224/0xc90 fs/read_write.c:679 1 lock held by syz.2.3/5339: #0: ffff88802cd59eb8 (&f->f_pos_lock){+.+.}-{3:3}, at: fdget_pos+0x24e/0x320 fs/file.c:1187 2 locks held by bch-copygc/loop/5334: 2 locks held by syz.0.91/5784: #0: ffff888059d520e0 (&type->s_umount_key#102){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff888059d520e0 (&type->s_umount_key#102){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff888059d52938 (&s->s_sync_lock){+.+.}-{3:3}, at: wait_sb_inodes fs/fs-writeback.c:2619 [inline] #1: ffff888059d52938 (&s->s_sync_lock){+.+.}-{3:3}, at: sync_inodes_sb+0x32e/0xb50 fs/fs-writeback.c:2802 2 locks held by syz.0.91/5787: #0: ffff888059d520e0 (&type->s_umount_key#102){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff888059d520e0 (&type->s_umount_key#102){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff888059d52938 (&s->s_sync_lock){+.+.}-{3:3}, at: wait_sb_inodes fs/fs-writeback.c:2619 [inline] #1: ffff888059d52938 (&s->s_sync_lock){+.+.}-{3:3}, at: sync_inodes_sb+0x32e/0xb50 fs/fs-writeback.c:2802 2 locks held by syz.0.91/5788: #0: ffff888059d520e0 (&type->s_umount_key#102){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff888059d520e0 (&type->s_umount_key#102){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff888059d52938 (&s->s_sync_lock){+.+.}-{3:3}, at: wait_sb_inodes fs/fs-writeback.c:2619 [inline] #1: ffff888059d52938 (&s->s_sync_lock){+.+.}-{3:3}, at: sync_inodes_sb+0x32e/0xb50 fs/fs-writeback.c:2802 2 locks held by syz-executor/6156: #0: ffff88805ec660e0 (&type->s_umount_key#74){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88805ec660e0 (&type->s_umount_key#74){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88805ec660e0 (&type->s_umount_key#74){++++}-{3:3}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8e93d200 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:4561 1 lock held by syz-executor/6486: #0: ffffffff8fcbef48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcbef48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 3 locks held by syz.2.202/6560: #0: ffff888059d520e0 (&type->s_umount_key#102){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff888059d520e0 (&type->s_umount_key#102){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff88805cf04398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:151 [inline] #1: ffff88805cf04398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:250 [inline] #1: ffff88805cf04398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7de/0xd20 fs/bcachefs/btree_iter.c:3215 #2: ffff88805cf266d0 (&c->gc_lock){.+.+}-{3:3}, at: bch2_btree_update_start+0x682/0x14e0 fs/bcachefs/btree_update_interior.c:1202 3 locks held by kworker/u8:9/6573: #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: ffffc9000425fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000425fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcbef48 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 8 locks held by syz-executor/6649: #0: ffff88807b51e420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline] #0: ffff88807b51e420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x224/0xc90 fs/read_write.c:679 #1: ffff88807251d888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #2: ffff888144f15a58 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f55cfc8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 #4: ffff8880751fd0e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff8880751fd0e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff8880751fd0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293 #5: ffff8880751fc250 (&devlink->lock_key#6){+.+.}-{3:3}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1672 #6: ffffffff8fcbef48 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x71/0x5c0 drivers/net/netdevsim/netdev.c:773 #7: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #7: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976 1 lock held by syz-executor/6689: #0: ffffffff8fcbef48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcbef48 (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-11728-gad46e8f95e93 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 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: 5334 Comm: bch-copygc/loop Not tainted 6.11.0-syzkaller-11728-gad46e8f95e93 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:should_print_err fs/bcachefs/bcachefs.h:327 [inline] RIP: 0010:bch2_evacuate_bucket+0xe33/0x34e0 fs/bcachefs/move.c:698 Code: 00 4c 89 e0 48 c1 e8 03 80 3c 10 00 48 8b 5c 24 18 74 08 4c 89 e7 e8 ac d1 bd fd 4d 8b 34 24 48 89 df e8 30 14 e3 ff 41 89 c7 <31> ff 89 c6 e8 44 46 57 fd 45 85 ff 48 8b 5c 24 28 74 51 31 ff 44 RSP: 0000:ffffc90004a47020 EFLAGS: 00000286 RAX: 0000000000000000 RBX: ffff88807a0b8000 RCX: ffff888029dc5a00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90004a47520 R08: ffffffff84208751 R09: 1ffff1100b9e0065 R10: dffffc0000000000 R11: ffffed100b9e0066 R12: ffffc90004a47410 R13: ffffc90004a473a0 R14: 0000000010000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6c3fdbd000 CR3: 000000000e734000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: bch2_copygc+0x3a03/0x4650 fs/bcachefs/movinggc.c:234 bch2_copygc_thread+0x737/0xc20 fs/bcachefs/movinggc.c:375 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