INFO: task syz.4.14:4408 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.14 state:D stack:24720 pid:4408 ppid:4275 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5246 [inline] __schedule+0x107f/0x4030 kernel/sched/core.c:6563 schedule+0xb9/0x180 kernel/sched/core.c:6639 do_uevent+0x1e9/0x490 fs/dlm/lockspace.c:210 new_lockspace fs/dlm/lockspace.c:659 [inline] __dlm_new_lockspace+0x1d6a/0x22b0 fs/dlm/lockspace.c:719 device_create_lockspace+0xc4/0x350 fs/dlm/user.c:426 device_write+0x893/0xea0 fs/dlm/user.c:618 vfs_write+0x2dc/0x9a0 fs/read_write.c:582 ksys_write+0x14d/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f482079e019 RSP: 002b:00007f48216a7028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f4820a25fa0 RCX: 00007f482079e019 RDX: 0000000000000078 RSI: 0000200000000400 RDI: 0000000000000007 RBP: 00007f482083500c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4820a26038 R14: 00007f4820a25fa0 R15: 00007ffed27ab7d8 Showing all locks held in the system: 6 locks held by kworker/u4:1/11: #0: ffff8880b8e3ad18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x25/0x130 kernel/sched/core.c:538 #1: ffff8880b8e27888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x400/0x740 kernel/sched/psi.c:999 #2: ffff88807a0a87a8 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: wiphy_lock include/net/cfg80211.h:5693 [inline] #2: ffff88807a0a87a8 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: cfg80211_wiphy_work+0x31/0x260 net/wireless/core.c:420 #3: ffff88805df04d40 (&wdev->mtx){+.+.}-{3:3}, at: sdata_lock net/mac80211/ieee80211_i.h:1114 [inline] #3: ffff88805df04d40 (&wdev->mtx){+.+.}-{3:3}, at: ieee80211_ibss_work+0xa8/0x1100 net/mac80211/ibss.c:1680 #4: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #4: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #4: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: ieee80211_sta_active_ibss+0xb1/0x320 net/mac80211/ibss.c:654 #5: ffff8880b8e3e9e0 (&c->lock){-.-.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] #5: ffff8880b8e3e9e0 (&c->lock){-.-.}-{2:2}, at: put_cpu_partial+0x6e/0x250 mm/slub.c:2639 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2e4f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8cb2ed10 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/27: #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6527 3 locks held by kworker/u4:3/47: 2 locks held by getty/4027: #0: ffff88802fa44098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41e/0x1360 drivers/tty/n_tty.c:2198 1 lock held by syz.4.14/4408: #0: ffffffff96d4d888 (&ls_lock){+.+.}-{3:3}, at: __dlm_new_lockspace+0xad/0x22b0 fs/dlm/lockspace.c:713 1 lock held by dlm_recoverd/4412: #0: ffff88801fe84ca0 (&ls->ls_in_recovery){+.+.}-{3:3}, at: dlm_recoverd+0xa6/0x1df0 fs/dlm/recoverd.c:312 ============================================= 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 07/24/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf0e/0xf50 kernel/hung_task.c:377 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 47 Comm: kworker/u4:3 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: bat_events batadv_nc_worker RIP: 0010:rcu_is_watching+0x6c/0xa0 kernel/rcu/tree.c:723 Code: c3 08 58 03 00 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 75 2f 8b 03 65 ff 0d 85 46 96 7e 74 0c 83 e0 04 c1 e8 02 5b <41> 5e 41 5f c3 e8 a2 5a 94 ff eb ed 48 c7 c7 00 3a b3 8c 48 89 de RSP: 0018:ffffc90000b87bc8 EFLAGS: 00000202 RAX: 0000000000000001 RBX: 0000000000000001 RCX: 1a821d092b83cd00 RDX: ffff88801a6a5a00 RSI: ffffffff8adf5dc0 RDI: ffffffff8adf5d80 RBP: ffff88801cb914d0 R08: dffffc0000000000 R09: 1ffffffff2162048 R10: dffffc0000000000 R11: fffffbfff2162049 R12: dffffc0000000000 R13: ffffffff89f9688e R14: ffffffff8c65f980 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055b731d65168 CR3: 000000000c88e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock include/linux/rcupdate.h:792 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0x108/0x600 net/batman-adv/network-coding.c:719 process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292 worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295