INFO: task syz-executor:5822 blocked for more than 143 seconds. Not tainted 6.15.0-rc1-syzkaller-00065-g3b07108ada81 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:20488 pid:5822 tgid:5822 ppid:1 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b33/0x51f0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x163/0x360 kernel/sched/core.c:6860 io_schedule+0x8d/0x110 kernel/sched/core.c:7742 folio_wait_bit_common+0x83f/0xf00 mm/filemap.c:1317 folio_wait_writeback+0xb0/0x100 mm/page-writeback.c:3149 __filemap_fdatawait_range+0x17e/0x2b0 mm/filemap.c:539 filemap_fdatawait_keep_errors+0x31/0xd0 mm/filemap.c:633 wait_sb_inodes fs/fs-writeback.c:2714 [inline] sync_inodes_sb+0x8bf/0xb50 fs/fs-writeback.c:2836 sync_filesystem+0x176/0x230 fs/sync.c:64 generic_shutdown_super+0x72/0x2d0 fs/super.c:621 bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2303 deactivate_locked_super+0xc4/0x130 fs/super.c:473 cleanup_mnt+0x422/0x4c0 fs/namespace.c:1435 task_work_run+0x251/0x310 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x13f/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb3c038e497 RSP: 002b:00007ffc5408d6e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fb3c040e51c RCX: 00007fb3c038e497 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc5408d7a0 RBP: 00007ffc5408d7a0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc5408e830 R13: 00007fb3c040e51c R14: 0000000000014325 R15: 00007ffc5408e870 INFO: task bch-rebalance/l:5938 blocked for more than 144 seconds. Not tainted 6.15.0-rc1-syzkaller-00065-g3b07108ada81 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:bch-rebalance/l state:D stack:17928 pid:5938 tgid:5938 ppid:2 task_flags:0x200040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b33/0x51f0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x163/0x360 kernel/sched/core.c:6860 bch2_move_ratelimit+0xcde/0x13a0 fs/bcachefs/move.c:522 do_rebalance fs/bcachefs/rebalance.c:527 [inline] bch2_rebalance_thread+0x1694/0x1fa0 fs/bcachefs/rebalance.c:588 kthread+0x7b7/0x940 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 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: 3 locks held by kworker/u8:0/12: #0: ffff88801bef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801bef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90000117c60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000117c60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff900de5d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17c/0xd60 net/core/net_namespace.c:608 1 lock held by khungtaskd/31: #0: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764 2 locks held by kworker/u8:2/36: #0: ffff88802e982148 ((wq_completion)btree_update){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88802e982148 ((wq_completion)btree_update){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90000ad7c60 ((work_completion)(&c->btree_interior_update_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000ad7c60 ((work_completion)(&c->btree_interior_update_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 2 locks held by kworker/1:1H/60: #0: ffff8880126f9948 ((wq_completion)bcachefs_btree_io){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff8880126f9948 ((wq_completion)bcachefs_btree_io){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc9000136fc60 ((work_completion)(&wb->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000136fc60 ((work_completion)(&wb->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 5 locks held by kworker/u8:4/64: 3 locks held by kworker/0:2/978: #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90003a5fc60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003a5fc60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffff88807fdcb240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x316/0x3f10 drivers/net/netdevsim/fib.c:1490 4 locks held by udevd/5200: #0: ffff888045919668 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb4/0xda0 fs/seq_file.c:182 #1: ffff888060a16c88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x53/0x3b0 fs/kernfs/file.c:154 #2: ffff888033ef9a58 (kn->active#5){++++}-{0:0}, at: kernfs_seq_start+0x72/0x3b0 fs/kernfs/file.c:155 #3: ffff88807fdce0e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #3: ffff88807fdce0e8 (&dev->mutex){....}-{4:4}, at: uevent_show+0x17d/0x340 drivers/base/core.c:2730 2 locks held by getty/5579: #0: ffff8880318530a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000334b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222 2 locks held by syz-executor/5822: #0: ffff888032b5a0e0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff888032b5a0e0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888032b5a0e0 (&type->s_umount_key#57){++++}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffff888032b5a948 (&s->s_sync_lock){+.+.}-{4:4}, at: wait_sb_inodes fs/fs-writeback.c:2653 [inline] #1: ffff888032b5a948 (&s->s_sync_lock){+.+.}-{4:4}, at: sync_inodes_sb+0x330/0xb50 fs/fs-writeback.c:2836 2 locks held by kworker/u9:8/5842: #0: ffff8880272f6148 ((wq_completion)bcachefs#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff8880272f6148 ((wq_completion)bcachefs#2){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc9000441fc60 ((work_completion)(&wp->index_update_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000441fc60 ((work_completion)(&wp->index_update_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 2 locks held by kworker/u9:10/5844: #0: ffff8880272f6148 ((wq_completion)bcachefs#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff8880272f6148 ((wq_completion)bcachefs#2){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc9000443fc60 ((work_completion)(&wp->index_update_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000443fc60 ((work_completion)(&wp->index_update_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 3 locks held by kworker/0:4/5878: #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc9000521fc60 ((work_completion)(&(&devlink->rwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000521fc60 ((work_completion)(&(&devlink->rwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff8ed434f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #2: ffffffff8ed434f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x384/0x830 kernel/rcu/tree_exp.h:998 1 lock held by syz.2.127/7177: #0: ffff888032b5a0e0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888032b5a0e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120 1 lock held by syz.2.127/7178: #0: ffff888032b5a0e0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888032b5a0e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120 1 lock held by syz.0.148/7406: #0: ffff888032b5a0e0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff888032b5a0e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x19b/0x400 fs/super.c:120 1 lock held by syz.4.183/7676: #0: ffff888032b5a0e0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888032b5a0e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120 1 lock held by syz.4.183/7696: #0: ffff888032b5a0e0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888032b5a0e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120 2 locks held by syz-executor/8232: #0: ffffffff900eb108 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff900eb108 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff900eb108 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xd68/0x1fe0 net/core/rtnetlink.c:4064 #1: ffff888077478d30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2751 [inline] #1: ffff888077478d30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline] #1: ffff888077478d30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: do_setlink+0x415/0x43a0 net/core/rtnetlink.c:3051 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc1-syzkaller-00065-g3b07108ada81 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 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+0x1058/0x10a0 kernel/hung_task.c:437 kthread+0x7b7/0x940 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 8232 Comm: syz-executor Not tainted 6.15.0-rc1-syzkaller-00065-g3b07108ada81 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:io_serial_out+0x7e/0xc0 drivers/tty/serial/8250/8250_port.c:416 Code: fc 89 e9 41 d3 e7 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 fc 58 9b fc 44 03 3b 44 89 f0 44 89 fa ee <5b> 41 5c 41 5e 41 5f 5d c3 cc cc cc cc 89 e9 80 e1 07 38 c1 7c a7 RSP: 0018:ffffc90004a7e350 EFLAGS: 00000002 RAX: 0000000000000034 RBX: ffffffff9aa4d980 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000020 RBP: 0000000000000000 R08: ffffffff858f92eb R09: 1ffff11004a4f046 R10: dffffc0000000000 R11: ffffffff858f92a0 R12: dffffc0000000000 R13: 0000000000000034 R14: 0000000000000034 R15: 00000000000003f8 FS: 000055557b107500(0000) GS:ffff8881250c9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2c340d35c0 CR3: 000000003b3de000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:-1 [inline] serial8250_console_write+0x1434/0x1e00 drivers/tty/serial/8250/8250_port.c:3456 console_emit_next_record kernel/printk/printk.c:3138 [inline] console_flush_all+0x86b/0xec0 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0x151/0x3b0 kernel/printk/printk.c:3325 vprintk_emit+0x761/0xa40 kernel/printk/printk.c:2450 dev_vprintk_emit+0x358/0x420 drivers/base/core.c:4891 dev_printk_emit+0xdf/0x130 drivers/base/core.c:4902 __netdev_printk+0x3e0/0x4d0 net/core/dev.c:12401 netdev_info+0x12d/0x180 net/core/dev.c:12456 netif_change_name+0x913/0xa20 net/core/dev.c:1412 do_setlink+0xe16/0x43a0 net/core/rtnetlink.c:3132 rtnl_changelink net/core/rtnetlink.c:3769 [inline] __rtnl_newlink net/core/rtnetlink.c:3928 [inline] rtnl_newlink+0x17e2/0x1fe0 net/core/rtnetlink.c:4065 rtnetlink_rcv_msg+0x80f/0xd70 net/core/rtnetlink.c:6955 netlink_rcv_skb+0x208/0x480 net/netlink/af_netlink.c:2534 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x7f8/0x9a0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x8c3/0xcd0 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:727 __sys_sendto+0x365/0x4c0 net/socket.c:2180 __do_sys_sendto net/socket.c:2187 [inline] __se_sys_sendto net/socket.c:2183 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2183 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2c3338effc Code: 2a 5f 02 00 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 70 5f 02 00 48 8b RSP: 002b:00007ffedb9364e0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f2c340d35c0 RCX: 00007f2c3338effc RDX: 0000000000000030 RSI: 00007f2c340d3610 RDI: 0000000000000006 RBP: 0000000000000000 R08: 00007ffedb936534 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000006 R13: 0000000000000000 R14: 00007f2c340d3610 R15: 0000000000000000