INFO: task syz-executor.0:4507 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.0 state:D stack:21808 pid: 4507 ppid: 1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 bit_wait+0xd/0xc0 kernel/sched/wait_bit.c:199 __wait_on_bit kernel/sched/wait_bit.c:49 [inline] out_of_line_wait_on_bit+0x173/0x230 kernel/sched/wait_bit.c:64 wait_on_bit include/linux/wait_bit.h:76 [inline] gfs2_glock_wait+0xd9/0x1c0 fs/gfs2/glock.c:1282 gfs2_glock_nq_init fs/gfs2/glock.h:246 [inline] __gfs2_lookup+0x12d/0x290 fs/gfs2/inode.c:883 __lookup_slow+0x29d/0x410 fs/namei.c:1671 lookup_slow+0x53/0x70 fs/namei.c:1688 walk_component+0x319/0x460 fs/namei.c:1984 lookup_last fs/namei.c:2439 [inline] path_lookupat+0x169/0x440 fs/namei.c:2463 filename_lookup+0x214/0x540 fs/namei.c:2492 user_path_at_empty+0x40/0x190 fs/namei.c:2891 user_path_at include/linux/namei.h:57 [inline] ksys_umount fs/namespace.c:1786 [inline] __do_sys_umount fs/namespace.c:1794 [inline] __se_sys_umount fs/namespace.c:1792 [inline] __x64_sys_umount+0xf9/0x170 fs/namespace.c:1792 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f9fd924ba57 RSP: 002b:00007ffe13d102f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 00007f9fd92ab3ef RCX: 00007f9fd924ba57 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe13d103b0 RBP: 00007ffe13d103b0 R08: 00007ffe13d113b0 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe13d114a0 R13: 00007f9fd92ab3ef R14: 0000555580f95450 R15: 0000000000000002 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c31eaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/3944: #0: ffff88814c850098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900026562e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158 1 lock held by syz-executor.0/4507: #0: ffff888068598ee0 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: inode_lock_shared include/linux/fs.h:797 [inline] #0: ffff888068598ee0 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: lookup_slow+0x46/0x70 fs/namei.c:1687 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] NMI backtrace for cpu 0 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:729