INFO: task syz-executor:6093 blocked for more than 143 seconds. Not tainted 6.14.0-syzkaller-01103-g2df0c02dab82 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21480 pid:6093 tgid:6093 ppid:1 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5367 [inline] __schedule+0x1ac3/0x5090 kernel/sched/core.c:6748 __schedule_loop kernel/sched/core.c:6825 [inline] schedule+0x163/0x360 kernel/sched/core.c:6840 schedule_timeout+0xb1/0x290 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x360/0x630 kernel/sched/completion.c:148 kthread_stop+0x1a1/0x640 kernel/kthread.c:791 bch2_copygc_stop+0x4f/0x150 fs/bcachefs/movinggc.c:413 __bch2_fs_read_only+0x47/0x450 fs/bcachefs/super.c:265 bch2_fs_read_only+0xc80/0x1360 fs/bcachefs/super.c:356 __bch2_fs_stop+0x107/0x5b0 fs/bcachefs/super.c:634 generic_shutdown_super+0x139/0x2d0 fs/super.c:642 bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2312 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: 0033:0x7ff09478e497 RSP: 002b:00007ffedac863f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007ff09480e08c RCX: 00007ff09478e497 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffedac864b0 RBP: 00007ffedac864b0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffedac87540 R13: 00007ff09480e08c R14: 000000000001d736 R15: 00007ffedac87580 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8eb3a760 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8eb3a760 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8eb3a760 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6761 3 locks held by kworker/1:1/47: #0: ffff88801ac80d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801ac80d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90000b77c60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000b77c60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffff888050b58240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x316/0x3f10 drivers/net/netdevsim/fib.c:1490 2 locks held by getty/5581: #0: ffff888035d610a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x53d/0x16b0 drivers/tty/n_tty.c:2211 1 lock held by udevd/6025: 2 locks held by syz-executor/6093: #0: ffff88805e2be0e0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88805e2be0e0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88805e2be0e0 (&type->s_umount_key#57){++++}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffff888050e80278 (&c->state_lock){+.+.}-{4:4}, at: __bch2_fs_stop+0xff/0x5b0 fs/bcachefs/super.c:633 1 lock held by syz.6.260/8393: #0: ffff88805e2be0e0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805e2be0e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120 1 lock held by syz.4.261/8415: #0: ffff88805e2be0e0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805e2be0e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120 1 lock held by syz-executor/8659: #0: ffffffff8eb3fc78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #0: ffffffff8eb3fc78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x454/0x830 kernel/rcu/tree_exp.h:998 1 lock held by dhcpcd/8959: #0: ffff88807b509a08 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff88807b509a08 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline] #0: ffff88807b509a08 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: sock_close+0x90/0x240 net/socket.c:1398 1 lock held by syz.9.345/9173: #0: ffff88805e2be0e0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805e2be0e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120 3 locks held by syz-executor/9545: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-syzkaller-01103-g2df0c02dab82 #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:236 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:399 kthread+0x7a9/0x920 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: 9695 Comm: syz.2.381 Not tainted 6.14.0-syzkaller-01103-g2df0c02dab82 #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 9c f3 a4 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:ffffc900049ee8d0 EFLAGS: 00000002 RAX: 0000000000000038 RBX: ffffffff9a7bf300 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: 000000000000a8e3 RDI: 000000000000a8e4 RBP: 0000000000000000 R08: ffffffff8583ef8b R09: 1ffff11004983046 R10: dffffc0000000000 R11: ffffffff8583ef40 R12: dffffc0000000000 R13: 0000000000000038 R14: 0000000000000038 R15: 00000000000003f8 FS: 00007f2838be46c0(0000) GS:ffff88812535a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2837fa7bac CR3: 0000000024fa4000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial8250_console_write+0x1434/0x1e00 drivers/tty/serial/8250/8250_port.c:3465 console_emit_next_record kernel/printk/printk.c:3120 [inline] console_flush_all+0x86b/0xec0 kernel/printk/printk.c:3208 __console_flush_and_unlock kernel/printk/printk.c:3267 [inline] console_unlock+0x151/0x3b0 kernel/printk/printk.c:3307 vprintk_emit+0x732/0xa10 kernel/printk/printk.c:2432 _printk+0xd5/0x120 kernel/printk/printk.c:2457 set_capacity_and_notify+0x215/0x2d0 block/genhd.c:93 loop_set_size+0x44/0xb0 drivers/block/loop.c:234 loop_configure+0xa93/0xf60 drivers/block/loop.c:1106 lo_ioctl+0x8a1/0x2870 blkdev_ioctl+0x5df/0x710 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:892 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: 0033:0x7f2837d8cd6b Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007f2838be3dc0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f2837d8cd6b RDX: 0000000000000003 RSI: 0000000000004c00 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000044b R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 00007f2838be3ef0 R14: 00007f2838be3eb0 R15: 00007f282d600000