INFO: task syz-executor:8471 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:20584 pid:8471 tgid:8471 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5254 [inline] __schedule+0x17c4/0x4d60 kernel/sched/core.c:6862 __schedule_loop kernel/sched/core.c:6944 [inline] schedule+0x165/0x360 kernel/sched/core.c:6959 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:1257 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: 0033:0x7f09f69902f7 RSP: 002b:00007ffc74ee2318 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 00007f09f6a11d7d RCX: 00007f09f69902f7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc74ee23d0 RBP: 00007ffc74ee23d0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc74ee34c0 R13: 00007f09f6a11d7d R14: 0000000000074999 R15: 00007ffc74ee5680 Showing all locks held in the system: 1 lock held by rcu_exp_gp_kthr/18: #0: ffff8880b863a018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:646 1 lock held by khungtaskd/31: #0: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5592: #0: ffff888033c400a0 (&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/8471: #0: ffff88805985a908 (&type->i_mutex_dir_key#24){.+.+}-{4:4}, at: inode_lock_shared include/linux/fs.h:995 [inline] #0: ffff88805985a908 (&type->i_mutex_dir_key#24){.+.+}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1832 2 locks held by syz-executor/10899: #0: ffff8880509480e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff8880509480e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff8880509480e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505 #1: ffffffff8df43178 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #1: ffffffff8df43178 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 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:337 [inline] watchdog+0xfa9/0xff0 kernel/hung_task.c:500 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: 11356 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:unwind_get_return_address+0x51/0x90 arch/x86/kernel/unwind_orc.c:369 Code: 3b 00 74 3a 48 83 c3 48 49 89 df 49 c1 ef 03 43 80 3c 37 00 74 08 48 89 df e8 0b 9f b2 00 48 8b 3b e8 83 e7 18 00 85 c0 74 14 <43> 80 3c 37 00 74 08 48 89 df e8 f0 9e b2 00 48 8b 03 eb 02 31 c0 RSP: 0018:ffffc9000b11f208 EFLAGS: 00000202 RAX: 0000000000000001 RBX: ffffc9000b11f270 RCX: b529cc39aef61900 RDX: ffffc9000b11f201 RSI: dffffc0000000000 RDI: ffffffff81ac595c RBP: ffffc9000b11f2b0 R08: ffffc9000b11f2b0 R09: 0000000000000000 R10: ffffc9000b11f278 R11: fffff52001623e51 R12: ffff8880299f1e40 R13: 1ffff92001623e70 R14: dffffc0000000000 R15: 1ffff92001623e4e FS: 000055557dc90500(0000) GS:ffff888125f29000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc6857b3ad8 CR3: 0000000032cc2000 CR4: 00000000003526f0 Call Trace: arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf5/0x1f0 mm/page_owner.c:165 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:320 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] free_unref_folios+0xd22/0x1460 mm/page_alloc.c:3005 folios_put_refs+0x584/0x670 mm/swap.c:1002 folio_batch_release include/linux/pagevec.h:101 [inline] shmem_undo_range+0x49e/0x14b0 mm/shmem.c:1120 shmem_truncate_range mm/shmem.c:1232 [inline] shmem_evict_inode+0x272/0xa70 mm/shmem.c:1360 evict+0x504/0x9c0 fs/inode.c:810 __dentry_kill+0x209/0x660 fs/dcache.c:669 dput+0x19f/0x2b0 fs/dcache.c:911 __fput+0x68e/0xa70 fs/file_table.c:476 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xe9/0x130 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5915b8dc2a Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 43 91 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 a3 91 02 00 8b 44 24 RSP: 002b:00007fffc15bf880 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007f5915b8dc2a RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007fffc15bf8dc R08: 0000000000000000 R09: 00007fffc15bf5e7 R10: 0000000000000000 R11: 0000000000000293 R12: 000000000000005a R13: 0000000000000011 R14: 00000000000988a2 R15: 00007fffc15bf930