INFO: task syz.5.5076:27171 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.5076 state:D stack:27960 pid:27171 tgid:27162 ppid:15382 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5352 [inline] __schedule+0x165c/0x5560 kernel/sched/core.c:6964 __schedule_loop kernel/sched/core.c:7047 [inline] schedule+0x164/0x360 kernel/sched/core.c:7062 schedule_timeout+0xc3/0x2c0 kernel/time/sleep_timeout.c:75 ___down_common kernel/locking/semaphore.c:289 [inline] __down_common+0x3d0/0x850 kernel/locking/semaphore.c:314 down+0x80/0xd0 kernel/locking/semaphore.c:100 console_lock+0x58/0x90 kernel/printk/printk.c:2896 class_console_lock_constructor include/linux/console.h:736 [inline] con_install+0x97/0x770 drivers/tty/vt/vt.c:3690 tty_driver_install_tty drivers/tty/tty_io.c:1295 [inline] tty_init_dev+0xd7/0x4d0 drivers/tty/tty_io.c:1407 tty_open_by_driver drivers/tty/tty_io.c:2073 [inline] tty_open+0x862/0xd70 drivers/tty/tty_io.c:2120 chrdev_open+0x4cd/0x5e0 fs/char_dev.c:411 do_dentry_open+0x785/0x14e0 fs/open.c:949 vfs_open+0x3b/0x340 fs/open.c:1081 do_open fs/namei.c:4693 [inline] path_openat+0x2e08/0x3860 fs/namei.c:4852 do_file_open+0x23e/0x4a0 fs/namei.c:4881 do_sys_openat2+0x113/0x200 fs/open.c:1366 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1383 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcedcb5cfce RSP: 002b:00007fcedadabb28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fcedadac6c0 RCX: 00007fcedcb5cfce RDX: 0000000000000002 RSI: 00007fcedadabc00 RDI: ffffffffffffff9c RBP: 00007fcedcc32c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fcedce16218 R14: 00007fcedce16180 R15: 00007ffc26e370e8 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e75d7e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e75d7e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e75d7e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5594: #0: ffff88803774f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211 3 locks held by syz.5.696/8894: 2 locks held by syz.9.4966/26831: 2 locks held by syz.5.5076/27171: #0: ffffffff8effac20 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline] #0: ffffffff8effac20 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x22d/0xd70 drivers/tty/tty_io.c:2120 #1: ffff88807b8b51b0 (&tty->legacy_mutex){+.+.}-{4:4}, at: tty_init_dev+0x74/0x4d0 drivers/tty/tty_io.c:1406 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xfd3/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 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: 8894 Comm: syz.5.696 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:match_held_lock+0x7b/0xb0 kernel/locking/lockdep.c:5337 Code: c7 c2 30 53 c6 93 48 29 d0 48 c1 f8 03 48 ba 29 5c 8f c2 f5 28 5c 8f 48 0f af d0 bb 01 00 00 00 48 39 ca 74 02 31 db 89 d8 5b <41> 5e e9 4e e7 02 00 cc 90 e8 a7 d1 fa f8 85 c0 74 1c 83 3d 40 a7 RSP: 0018:ffffc9001080efa8 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff88805d8f8bc8 RCX: 0000000000000046 RDX: ffff88805d8f8000 RSI: ffff888057642ed8 RDI: ffff88805d8f8bc8 RBP: 00000000ffffffff R08: ffffffff8201922d R09: ffffffff8e75d7e0 R10: ffffc9001080f0e0 R11: fffff52002101e1f R12: 0000000000000246 R13: ffff88805d8f8000 R14: ffff888057642ed8 R15: 0000000000000003 FS: 00007f02ad4836c0(0000) GS:ffff888125448000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055a855f48660 CR3: 0000000035606000 CR4: 00000000003526f0 DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083 DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: __lock_is_held kernel/locking/lockdep.c:5601 [inline] lock_is_held_type+0x89/0x150 kernel/locking/lockdep.c:5940 lock_is_held include/linux/lockdep.h:249 [inline] xa_entry include/linux/xarray.h:1226 [inline] xas_descend lib/xarray.c:208 [inline] xas_load+0x1b5/0x5b0 lib/xarray.c:246 filemap_get_entry+0x181/0x3f0 mm/filemap.c:1901 __filemap_get_folio_mpol+0x6d/0xb00 mm/filemap.c:1947 __filemap_get_folio include/linux/pagemap.h:774 [inline] filemap_grab_folio include/linux/pagemap.h:854 [inline] nilfs_grab_buffer+0xae/0x490 fs/nilfs2/page.c:56 nilfs_mdt_submit_block+0xb5/0x840 fs/nilfs2/mdt.c:123 nilfs_mdt_read_block+0x46/0x320 fs/nilfs2/mdt.c:178 nilfs_mdt_get_block+0x13f/0xb00 fs/nilfs2/mdt.c:254 nilfs_cpfile_get_checkpoint_block fs/nilfs2/cpfile.c:181 [inline] nilfs_cpfile_delete_checkpoints+0x2b2/0xce0 fs/nilfs2/cpfile.c:487 nilfs_ioctl_delete_checkpoints fs/nilfs2/ioctl.c:680 [inline] nilfs_ioctl_prepare_clean_segments+0x158/0x800 fs/nilfs2/ioctl.c:781 nilfs_clean_segments+0x18c/0xa50 fs/nilfs2/segment.c:2525 nilfs_ioctl_clean_segments fs/nilfs2/ioctl.c:916 [inline] nilfs_ioctl+0x261f/0x2780 fs/nilfs2/ioctl.c:1346 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f02ac59c799 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f02ad483028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f02ac815fa0 RCX: 00007f02ac59c799 RDX: 0000200000000640 RSI: 0000000040786e88 RDI: 0000000000000007 RBP: 00007f02ac632c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f02ac816038 R14: 00007f02ac815fa0 R15: 00007ffd96be2618