INFO: task syz-executor:5868 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:21736 pid:5868 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5380 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699 schedule+0xbd/0x170 kernel/sched/core.c:6773 bit_wait+0x11/0xd0 kernel/sched/wait_bit.c:199 __wait_on_bit+0xac/0x2d0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x123/0x170 kernel/sched/wait_bit.c:64 wait_on_bit include/linux/wait_bit.h:76 [inline] gfs2_glock_wait+0xbd/0x2a0 fs/gfs2/glock.c:1380 gfs2_glock_nq_init fs/gfs2/glock.h:252 [inline] __gfs2_lookup+0x118/0x270 fs/gfs2/inode.c:905 __lookup_slow+0x281/0x3b0 fs/namei.c:1702 lookup_slow+0x53/0x70 fs/namei.c:1719 walk_component+0x2be/0x3f0 fs/namei.c:2010 lookup_last fs/namei.c:2467 [inline] path_lookupat+0x169/0x440 fs/namei.c:2491 filename_lookup+0x1f4/0x510 fs/namei.c:2520 user_path_at_empty+0x42/0x60 fs/namei.c:2917 user_path_at include/linux/namei.h:57 [inline] ksys_umount fs/namespace.c:1921 [inline] __do_sys_umount fs/namespace.c:1929 [inline] __se_sys_umount fs/namespace.c:1927 [inline] __x64_sys_umount+0xf5/0x170 fs/namespace.c:1927 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f79db590a77 RSP: 002b:00007fff741e57a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 00007f79db613d7d RCX: 00007f79db590a77 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff741e5860 RBP: 00007fff741e5860 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff741e6950 R13: 00007f79db613d7d R14: 000055558c83b4a8 R15: 00007fff741e8b10 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: #0: ffff8880b8e3c018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 1 lock held by khungtaskd/29: #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 1 lock held by dhcpcd/5428: #0: ffff8880b8f3c018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 2 locks held by getty/5523: #0: ffff88802d2010a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000327e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217 1 lock held by syz-executor/5868: #0: ffff88805f161588 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: inode_lock_shared include/linux/fs.h:814 [inline] #0: ffff88805f161588 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: lookup_slow+0x46/0x70 fs/namei.c:1718 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf41/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 6569 Comm: syz.1.222 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x10/0x60 kernel/kcov.c:216 Code: 89 fb e8 13 00 00 00 48 8b 3d 9c 92 c4 0c 48 89 de 5b e9 43 9d 56 00 cc cc cc f3 0f 1e fa 48 8b 04 24 65 48 8b 0d f0 24 7e 7e <65> 8b 15 f1 24 7e 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 RSP: 0018:ffffc90004987770 EFLAGS: 00000202 RAX: ffffffff81e7cc24 RBX: ffffffff81e7cbe2 RCX: ffff888027548000 RDX: ffff888027548000 RSI: ffffffff8afc6f60 RDI: ffffffff8afc6f20 RBP: 0000000000000001 R08: dffffc0000000000 R09: 1ffffffff21b28a0 R10: dffffc0000000000 R11: fffffbfff21b28a1 R12: 00fff00000000000 R13: dffffc0000000000 R14: ffffea0001d23340 R15: ffffea0001d23340 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f79a2fe7dac CR3: 000000000cb30000 CR4: 00000000003506e0 Call Trace: rcu_read_lock include/linux/rcupdate.h:787 [inline] page_ext_get+0x64/0x2b0 mm/page_ext.c:508 __page_table_check_zero+0x138/0x4b0 mm/page_table_check.c:148 page_table_check_free include/linux/page_table_check.h:41 [inline] free_pages_prepare mm/page_alloc.c:1155 [inline] free_unref_page_prepare+0x7e1/0x8e0 mm/page_alloc.c:2336 free_unref_page_list+0xbe/0x860 mm/page_alloc.c:2475 release_pages+0x1fa0/0x2220 mm/swap.c:1022 tlb_batch_pages_flush mm/mmu_gather.c:98 [inline] tlb_flush_mmu_free mm/mmu_gather.c:293 [inline] tlb_flush_mmu+0x368/0x4f0 mm/mmu_gather.c:300 tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:392 exit_mmap+0x3f0/0xb50 mm/mmap.c:3315 __mmput+0x118/0x3c0 kernel/fork.c:1355 exit_mm+0x1da/0x2c0 kernel/exit.c:569 do_exit+0x88e/0x23c0 kernel/exit.c:870 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024 __do_sys_exit_group kernel/exit.c:1035 [inline] __se_sys_exit_group kernel/exit.c:1033 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1033 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f79a2d8f749 Code: Unable to access opcode bytes at 0x7f79a2d8f71f. RSP: 002b:00007ffcb9edf9a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f79a2d8f749 RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffcb9edfa0c R08: 00000002b9edfa9f R09: 00000000000927c0 R10: 0000000000000001 R11: 0000000000000246 R12: 00000000000000cb R13: 00000000000927c0 R14: 000000000003874d R15: 00007ffcb9edfa60