INFO: task syz.1.17:6748 blocked for more than 143 seconds. Not tainted 6.15.0-rc6-syzkaller-g82f2b0b97b36 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.17 state:D stack:21192 pid:6748 tgid:6746 ppid:6585 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 __closure_sync+0x163/0x220 lib/closure.c:146 closure_sync include/linux/closure.h:195 [inline] bch2_set_nr_journal_buckets_loop+0x131d/0x16d0 fs/bcachefs/journal.c:1278 bch2_dev_journal_alloc fs/bcachefs/journal.c:1321 [inline] bch2_fs_journal_alloc+0x13d/0x280 fs/bcachefs/journal.c:1333 bch2_run_recovery_pass+0xdf/0x1d0 fs/bcachefs/recovery_passes.c:227 bch2_run_recovery_passes+0x2a0/0xdb0 fs/bcachefs/recovery_passes.c:280 bch2_fs_recovery+0x2399/0x37b0 fs/bcachefs/recovery.c:937 bch2_fs_start+0x70b/0xae0 fs/bcachefs/super.c:1096 bch2_fs_get_tree+0xad7/0x13b0 fs/bcachefs/fs.c:2505 vfs_get_tree+0x8f/0x2b0 fs/super.c:1759 do_new_mount+0x24a/0xa40 fs/namespace.c:3881 do_mount fs/namespace.c:4221 [inline] __do_sys_mount fs/namespace.c:4432 [inline] __se_sys_mount+0x317/0x410 fs/namespace.c:4409 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1ea55874ca RSP: 002b:00007f1ea6335e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f1ea6335ef0 RCX: 00007f1ea55874ca RDX: 0000000020000500 RSI: 0000000020005900 RDI: 00007f1ea6335eb0 RBP: 0000000020000500 R08: 00007f1ea6335ef0 R09: 0000000001000000 R10: 0000000001000000 R11: 0000000000000246 R12: 0000000020005900 R13: 00007f1ea6335eb0 R14: 0000000000005907 R15: 00000000200001c0 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: #0: ffffffff8dde4e28 (wq_pool_mutex){+.+.}-{4:4}, at: pwq_release_workfn+0x3dc/0x870 kernel/workqueue.c:5091 1 lock held by ksoftirqd/0/15: #0: ffff8880b88399d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605 1 lock held by khungtaskd/31: #0: ffffffff8df3d860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3d860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3d860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 2 locks held by getty/5586: #0: ffff8880308940a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036c32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 2 locks held by syz.3.288/9863: 2 locks held by syz.5.289/9865: 3 locks held by syz.4.290/9867: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-g82f2b0b97b36 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 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+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x70e/0x8a0 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 9857 Comm: syz.0.287 Not tainted 6.15.0-rc6-syzkaller-g82f2b0b97b36 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:io_serial_out+0x7c/0xc0 drivers/tty/serial/8250/8250_port.c:416 Code: 21 89 fc 44 89 f9 d3 e5 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 ec f0 e8 fc 41 03 2e 89 d8 89 ea ee <5b> 41 5c 41 5e 41 5f 5d c3 cc cc cc cc cc 44 89 f9 80 e1 07 38 c1 RSP: 0018:ffffc90003c06f10 EFLAGS: 00000002 RAX: 0000000000000037 RBX: 0000000000000037 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000020 RBP: 00000000000003f8 R08: ffff888023ee0237 R09: 1ffff110047dc046 R10: dffffc0000000000 R11: ffffffff8536ac30 R12: dffffc0000000000 R13: ffffffff99817c46 R14: ffffffff99b1c9c0 R15: 0000000000000000 FS: 00007fb5d92786c0(0000) GS:ffff8881260fb000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007efe93f1f000 CR3: 0000000033be0000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_port_out include/linux/serial_core.h:796 [inline] serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3306 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:-1 [inline] serial8250_console_write+0x140d/0x1ba0 drivers/tty/serial/8250/8250_port.c:3456 console_emit_next_record kernel/printk/printk.c:3138 [inline] console_flush_all+0x725/0xc40 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xc4/0x270 kernel/printk/printk.c:3325 vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450 bch2_print_maybe_redirect fs/bcachefs/super.c:110 [inline] __bch2_print+0x176/0x220 fs/bcachefs/super.c:129 bch2_fs_online+0xe1/0x4b0 fs/bcachefs/super.c:697 bch2_fs_alloc fs/bcachefs/super.c:973 [inline] bch2_fs_open+0x27db/0x2820 fs/bcachefs/super.c:2210 bch2_fs_get_tree+0x45d/0x13b0 fs/bcachefs/fs.c:2489 vfs_get_tree+0x8f/0x2b0 fs/super.c:1759 do_new_mount+0x24a/0xa40 fs/namespace.c:3881 do_mount fs/namespace.c:4221 [inline] __do_sys_mount fs/namespace.c:4432 [inline] __se_sys_mount+0x317/0x410 fs/namespace.c:4409 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb5d83874ca Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb5d9277e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fb5d9277ef0 RCX: 00007fb5d83874ca RDX: 0000000020000500 RSI: 0000000020005900 RDI: 00007fb5d9277eb0 RBP: 0000000020000500 R08: 00007fb5d9277ef0 R09: 0000000001000000 R10: 0000000001000000 R11: 0000000000000246 R12: 0000000020005900 R13: 00007fb5d9277eb0 R14: 0000000000005907 R15: 00000000200001c0