INFO: task syz-executor:5828 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21256 pid:5828 tgid:5828 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 bit_wait+0x11/0xd0 kernel/sched/wait_bit.c:240 __wait_on_bit+0xb9/0x310 kernel/sched/wait_bit.c:52 out_of_line_wait_on_bit+0x123/0x170 kernel/sched/wait_bit.c:67 wait_on_bit include/linux/wait_bit.h:77 [inline] gfs2_glock_wait+0xbd/0x2a0 fs/gfs2/glock.c:1335 gfs2_glock_nq_init fs/gfs2/glock.h:252 [inline] __gfs2_lookup+0x117/0x270 fs/gfs2/inode.c:984 __lookup_slow+0x297/0x3d0 fs/namei.c:1816 lookup_slow+0x53/0x70 fs/namei.c:1833 walk_component+0x2d2/0x400 fs/namei.c:2151 lookup_last fs/namei.c:2652 [inline] path_lookupat+0x163/0x430 fs/namei.c:2676 filename_lookup+0x212/0x570 fs/namei.c:2705 user_path_at+0x3a/0x60 fs/namei.c:3215 ksys_umount fs/namespace.c:2061 [inline] __do_sys_umount fs/namespace.c:2069 [inline] __se_sys_umount fs/namespace.c:2067 [inline] __x64_sys_umount+0xee/0x160 fs/namespace.c:2067 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb2063902f7 RSP: 002b:00007ffeb300e618 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 00007fb206411d7d RCX: 00007fb2063902f7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffeb300e6d0 RBP: 00007ffeb300e6d0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffeb300f7c0 R13: 00007fb206411d7d R14: 0000000000078f91 R15: 00007ffeb3011980 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3d2e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3d2e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df3d2e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/u8:8/3028: #0: ffff8880b883a058 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:646 #1: ffff8880b8824048 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 2 locks held by getty/5586: #0: ffff888032fab0a0 (&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+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5828: #0: ffff888058233648 (&type->i_mutex_dir_key#10){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:995 [inline] #0: ffff888058233648 (&type->i_mutex_dir_key#10){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1832 2 locks held by udevd/5843: 3 locks held by kworker/0:4/5887: 2 locks held by syz.0.1178/11267: #0: ffff8880583fe988 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline] #0: ffff8880583fe988 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline] #0: ffff8880583fe988 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1455 #1: ffffffff8df42d78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #1: ffffffff8df42d78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline] watchdog+0xf60/0xfa0 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 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: 6071 Comm: kworker/u8:11 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: 0x0 (events_unbound) RIP: 0010:srso_alias_safe_ret+0x0/0x7 arch/x86/lib/retpoline.S:210 Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc <48> 8d 64 24 08 c3 cc e8 f4 ff ff ff 0f 0b cc cc cc cc cc cc cc cc RSP: 0018:ffffc9000b057c50 EFLAGS: 00000093 RAX: ffffffff818bbc52 RBX: 1ffff1100340f00c RCX: 0000000000000000 RDX: ffff88807e9f9e40 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff5200160af68 R12: ffff88801a078060 R13: dffffc0000000000 R14: ffff888057e4e278 R15: 0000000000000088 FS: 0000000000000000(0000) GS:ffff88812613e000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7cef9b3ad8 CR3: 000000007fbc7000 CR4: 0000000000350ef0 Call Trace: srso_alias_return_thunk+0x5/0xfbef5 arch/x86/lib/retpoline.S:220 worker_clr_flags kernel/workqueue.c:1005 [inline] worker_thread+0x7b2/0xda0 kernel/workqueue.c:3419 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 vkms_vblank_simulate: vblank timer overrun