INFO: task kworker/u8:1:12 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-10547-g684a64bf32b6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:1 state:D stack:21200 pid:12 tgid:12 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-bcachefs-9) 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 io_schedule+0x8d/0x110 kernel/sched/core.c:7552 folio_wait_bit_common+0x882/0x12b0 mm/filemap.c:1309 folio_lock include/linux/pagemap.h:1148 [inline] writeback_get_folio mm/page-writeback.c:2496 [inline] writeback_iter+0x992/0x18d0 mm/page-writeback.c:2590 write_cache_pages+0xb1/0x230 mm/page-writeback.c:2639 bch2_writepages+0x14f/0x380 fs/bcachefs/fs-io-buffered.c:639 do_writepages+0x35d/0x870 mm/page-writeback.c:2683 __writeback_single_inode+0x14f/0x10d0 fs/fs-writeback.c:1658 writeback_sb_inodes+0x80c/0x1370 fs/fs-writeback.c:1954 __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:2025 wb_writeback+0x42f/0xbd0 fs/fs-writeback.c:2136 wb_check_background_flush fs/fs-writeback.c:2206 [inline] wb_do_writeback fs/fs-writeback.c:2294 [inline] wb_workfn+0xc58/0x1090 fs/fs-writeback.c:2321 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 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 INFO: task syz.3.38:5623 blocked for more than 144 seconds. Not tainted 6.11.0-syzkaller-10547-g684a64bf32b6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.38 state:D stack:22928 pid:5623 tgid:5573 ppid:5221 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 io_schedule+0x8d/0x110 kernel/sched/core.c:7552 folio_wait_bit_common+0x882/0x12b0 mm/filemap.c:1309 folio_wait_writeback+0xe7/0x1e0 mm/page-writeback.c:3189 folio_prepare_writeback mm/page-writeback.c:2455 [inline] writeback_get_folio mm/page-writeback.c:2497 [inline] writeback_iter+0xb18/0x18d0 mm/page-writeback.c:2590 write_cache_pages+0xb1/0x230 mm/page-writeback.c:2639 bch2_writepages+0x14f/0x380 fs/bcachefs/fs-io-buffered.c:639 do_writepages+0x35d/0x870 mm/page-writeback.c:2683 filemap_fdatawrite_wbc+0x125/0x180 mm/filemap.c:398 __filemap_fdatawrite_range mm/filemap.c:431 [inline] filemap_write_and_wait_range+0x192/0x280 mm/filemap.c:685 bch2_extend fs/bcachefs/fs-io.c:378 [inline] bchfs_truncate+0x64b/0xc70 fs/bcachefs/fs-io.c:431 notify_change+0xbca/0xe90 fs/attr.c:503 do_truncate+0x220/0x310 fs/open.c:65 vfs_truncate+0x2e1/0x3b0 fs/open.c:111 do_sys_truncate+0xdb/0x190 fs/open.c:134 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: 0033:0x7f347477def9 RSP: 002b:00007f3475510038 EFLAGS: 00000246 ORIG_RAX: 000000000000004c RAX: ffffffffffffffda RBX: 00007f3474936130 RCX: 00007f347477def9 RDX: 0000000000000000 RSI: 000000000000f000 RDI: 0000000020000080 RBP: 00007f34747f0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f3474936130 R15: 00007ffcab4f5c58 Showing all locks held in the system: 3 locks held by kworker/0:1/9: #0: ffff88801ac81148 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac81148 ((wq_completion)events_long){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc900000e7d00 ((work_completion)(&c->read_only_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900000e7d00 ((work_completion)(&c->read_only_work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffff888063780278 (&c->state_lock){+.+.}-{3:3}, at: bch2_fs_read_only_work+0x25/0x40 fs/bcachefs/super.c:391 2 locks held by kworker/u8:0/11: 3 locks held by kworker/u8:1/12: #0: ffff8881432e2948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff8881432e2948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000117d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000117d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffff88801bb160e0 (&type->s_umount_key#55){++++}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562 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/u8:9/2553: #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: ffffc900091e7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900091e7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcb2910 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580 #3: ffff88807d6d9428 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_destruct+0x110/0x2e0 drivers/net/wireguard/device.c:249 #4: ffffffff8e93d478 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #4: ffffffff8e93d478 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 2 locks held by getty/4974: #0: ffff88802e84f0a0 (&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 1 lock held by syz.3.38/5574: #0: ffff88801bb16420 (sb_writers#15){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x220 fs/splice.c:1163 2 locks held by syz.3.38/5623: #0: ffff88801bb16420 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 #1: ffff88805af2a6a0 (&sb->s_type->i_mutex_key#22){++++}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #1: ffff88805af2a6a0 (&sb->s_type->i_mutex_key#22){++++}-{3:3}, at: do_truncate+0x20c/0x310 fs/open.c:63 3 locks held by bch-copygc/loop/5610: 1 lock held by syz.3.111/6158: #0: ffff88801bb160e0 (&type->s_umount_key#55){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88801bb160e0 (&type->s_umount_key#55){++++}-{3:3}, at: super_lock+0x196/0x400 fs/super.c:120 2 locks held by syz-executor/6254: #0: ffff888048b700e0 (&type->s_umount_key#55){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff888048b700e0 (&type->s_umount_key#55){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888048b700e0 (&type->s_umount_key#55){++++}-{3:3}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffff888063780278 (&c->state_lock){+.+.}-{3:3}, at: __bch2_fs_stop+0xfd/0x540 fs/bcachefs/super.c:618 1 lock held by syz-executor/6517: #0: ffffffff8e93d478 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #0: ffffffff8e93d478 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 1 lock held by syz.3.147/6538: #0: ffff88801bb160e0 (&type->s_umount_key#55){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88801bb160e0 (&type->s_umount_key#55){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 1 lock held by syz.3.147/6539: #0: ffff88801bb160e0 (&type->s_umount_key#55){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88801bb160e0 (&type->s_umount_key#55){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 1 lock held by syz.2.176/6675: #0: ffff88801bb160e0 (&type->s_umount_key#55){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88801bb160e0 (&type->s_umount_key#55){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 7 locks held by syz-executor/6755: #0: ffff88802e310420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline] #0: ffff88802e310420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x224/0xc90 fs/read_write.c:679 #1: ffff888078473488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #2: ffff888143b6f4b8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f55e488 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 #4: ffff88807cdfa0e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff88807cdfa0e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff88807cdfa0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293 #5: ffff88807cdff250 (&devlink->lock_key#11){+.+.}-{3:3}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1672 #6: ffffffff8e93d340 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:4561 1 lock held by syz.3.196/6767: #0: ffff88801bb160e0 (&type->s_umount_key#55){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88801bb160e0 (&type->s_umount_key#55){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-10547-g684a64bf32b6 #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: 5610 Comm: bch-copygc/loop Not tainted 6.11.0-syzkaller-10547-g684a64bf32b6 #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:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x8/0x90 kernel/kcov.c:300 Code: cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 4c 8b 04 24 <65> 48 8b 14 25 80 d7 03 00 65 8b 05 80 1f 6f 7e 25 00 01 ff 00 74 RSP: 0018:ffffc90009ea6630 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff84444505 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff88807dd94380 R08: ffffffff84153cc5 R09: 1ffff1100f91ec00 R10: dffffc0000000000 R11: ffffed100f91ec01 R12: 0000000000000198 R13: ffff88807dd9437a R14: ffff88807dd941c8 R15: 1ffff1100fbb286f FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe179a3f000 CR3: 000000007cacc000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: btree_path_copy fs/bcachefs/btree_iter.c:1221 [inline] btree_path_clone fs/bcachefs/btree_iter.c:1230 [inline] __bch2_btree_path_make_mut+0x285/0x6c0 fs/bcachefs/btree_iter.c:1244 bch2_btree_path_make_mut fs/bcachefs/btree_iter.h:214 [inline] __bch2_btree_path_set_pos+0x382/0x1710 fs/bcachefs/btree_iter.c:1262 bch2_btree_path_set_pos fs/bcachefs/btree_iter.h:229 [inline] bch2_btree_iter_peek_upto+0x533d/0x6f00 fs/bcachefs/btree_iter.c:2394 bch2_btree_iter_peek_upto_type fs/bcachefs/btree_iter.h:685 [inline] bch2_get_next_backpointer+0x8bb/0x1320 fs/bcachefs/backpointers.c:246 bch2_evacuate_bucket+0x1075/0x34e0 fs/bcachefs/move.c:708 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