INFO: task syz.8.792:10012 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.8.792 state:D stack:24816 pid:10012 tgid:10011 ppid:9306 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x16dc/0x5500 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 do_uevent+0x2c3/0x570 fs/dlm/lockspace.c:206 new_lockspace fs/dlm/lockspace.c:583 [inline] __dlm_new_lockspace+0x1aa4/0x2060 fs/dlm/lockspace.c:638 user_cluster_connect+0x231/0xcc0 fs/ocfs2/stack_user.c:976 ocfs2_cluster_connect+0x445/0x720 fs/ocfs2/stackglue.c:355 ocfs2_cluster_connect_agnostic+0x6e/0x90 fs/ocfs2/stackglue.c:385 user_dlm_register+0xd2/0x210 fs/ocfs2/dlmfs/userdlm.c:669 dlmfs_mkdir+0x13c/0x340 fs/ocfs2/dlmfs/dlmfs.c:434 vfs_mkdir+0x402/0x620 fs/namei.c:5276 filename_mkdirat+0x289/0x520 fs/namei.c:5309 __do_sys_mkdir fs/namei.c:5336 [inline] __se_sys_mkdir+0x34/0x150 fs/namei.c:5333 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9b7ec2e0d9 RSP: 002b:00007f9b7ce86028 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007f9b7eeb5fa0 RCX: 00007f9b7ec2e0d9 RDX: 0000000000000000 RSI: 00000000000001ff RDI: 0000200000000640 RBP: 00007f9b7ecc5024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9b7eeb6038 R14: 00007f9b7eeb5fa0 R15: 00007ffef55d2eb8 Showing all locks held in the system: 1 lock held by khungtaskd/37: #0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5341: #0: ffff8880325a80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211 5 locks held by kworker/u8:86/9192: 3 locks held by syz.8.792/10012: #0: ffff88803a196500 (sb_writers#21){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494 #1: ffff8880446e5600 (&sb->s_type->i_mutex_key#33/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline] #1: ffff8880446e5600 (&sb->s_type->i_mutex_key#33/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline] #1: ffff8880446e5600 (&sb->s_type->i_mutex_key#33/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline] #1: ffff8880446e5600 (&sb->s_type->i_mutex_key#33/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4955 #2: ffffffff99bcf498 (&ls_lock){+.+.}-{4:4}, at: __dlm_new_lockspace+0xa3/0x2060 fs/dlm/lockspace.c:632 1 lock held by dlm_recoverd/10019: #0: ffff8880251c0d20 (&ls->ls_in_recovery){+.+.}-{4:4}, at: dlm_recoverd+0xba/0x23e0 fs/dlm/recoverd.c:400 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122 nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65 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+0xfd7/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 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: 9192 Comm: kworker/u8:86 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: bat_events batadv_tt_purge RIP: 0010:__lock_acquire+0x6a3/0x2ce0 kernel/locking/lockdep.c:5207 Code: ba 08 00 00 00 e8 7d 44 00 00 31 ed 85 c0 0f 84 19 0d 00 00 83 3d 6c 41 08 18 00 75 13 48 63 44 24 20 48 0f a3 05 3d b1 04 12 <0f> 83 5d 1e 00 00 49 8b 9e f8 0b 00 00 48 83 3c 24 00 75 1e 48 83 RSP: 0018:ffffc9000ca2f7a0 EFLAGS: 00000047 RAX: 000000000000000b RBX: ffff888032552ba0 RCX: ffffffff93471d68 RDX: 0000000000000008 RSI: ffff888032552b80 RDI: ffff888032551f00 RBP: 0000000000000000 R08: ffffffff8188621c R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8e1c3000 R12: 0000000000000003 R13: ffff888032552b80 R14: ffff888032551f00 R15: 0000000000000003 FS: 0000000000000000(0000) GS:ffff888125c3a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005582ae365a38 CR3: 000000000dfb0000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 rcu_lock_acquire include/linux/rcupdate.h:300 [inline] rcu_read_lock include/linux/rcupdate.h:840 [inline] __local_bh_disable_ip+0x205/0x420 kernel/softirq.c:174 local_bh_disable include/linux/bottom_half.h:20 [inline] spin_lock_bh include/linux/spinlock_rt.h:89 [inline] batadv_tt_local_purge+0x131/0x380 net/batman-adv/translation-table.c:1364 batadv_tt_purge+0x35/0x9f0 net/batman-adv/translation-table.c:3565 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245