INFO: task syz-executor:8113 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:22504 pid:8113 tgid:8113 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1480/0x50a0 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7241 rt_mutex_slowlock_block+0x5ba/0x6d0 kernel/locking/rtmutex.c:1647 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline] rt_mutex_slowlock+0x2a8/0x6b0 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:534 [inline] mutex_lock_nested+0x16a/0x1d0 kernel/locking/rtmutex_api.c:552 add_one_compat_dev+0xf0/0x650 drivers/infiniband/core/device.c:979 rdma_dev_init_net+0x238/0x2f0 drivers/infiniband/core/device.c:1221 ops_init+0x35c/0x5c0 net/core/net_namespace.c:137 setup_net+0x110/0x330 net/core/net_namespace.c:446 copy_net_ns+0x3e3/0x570 net/core/net_namespace.c:581 create_new_namespaces+0x3e7/0x6a0 kernel/nsproxy.c:130 unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:226 ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3171 __do_sys_unshare kernel/fork.c:3242 [inline] __se_sys_unshare kernel/fork.c:3240 [inline] __x64_sys_unshare+0x38/0x50 kernel/fork.c:3240 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9cf35b0f47 RSP: 002b:00007ffdc97fc138 EFLAGS: 00000202 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007f9cf3805f40 RCX: 00007f9cf35b0f47 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 00007f9cf38067b8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008 R13: 0000000000000003 R14: 00007ffdc97fc408 R15: 0000000000000000 Showing all locks held in the system: 5 locks held by kworker/u8:0/12: 1 lock held by ktimers/1/29: #0: ffff8880b883b6d8 (&rq->__lock){-...}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:647 2 locks held by kworker/1:0/31: 1 lock held by khungtaskd/38: #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:2/44: 3 locks held by kworker/u8:3/45: 6 locks held by kworker/u8:4/69: 3 locks held by kworker/u8:5/152: 3 locks held by kworker/0:2/191: 7 locks held by kworker/u8:6/1008: 3 locks held by kworker/u8:7/1053: 2 locks held by kworker/u8:8/1163: 6 locks held by kworker/u8:10/1510: #0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc9000534fb80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000534fb80 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffffffff8e88e320 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x7b0 net/core/net_namespace.c:670 #3: ffff88802ecb30d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #3: ffff88802ecb30d8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff88802ecb30d8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x10a/0x3d0 net/devlink/core.c:506 #4: ffff88802ecb4300 (&devlink->lock_key){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline] #4: ffff88802ecb4300 (&devlink->lock_key){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #4: ffff88802ecb4300 (&devlink->lock_key){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x11c/0x3d0 net/devlink/core.c:506 #5: ffffffff8e89b438 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0xed/0x680 drivers/net/netdevsim/netdev.c:1175 3 locks held by kworker/u8:12/2221: #0: ffff88814d96b138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88814d96b138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc900058efb80 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc900058efb80 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffffffff8e89b438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8e89b438 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4734 1 lock held by syslogd/5147: 5 locks held by udevd/5165: #0: ffffffff8d66d4d0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1528 [inline] #0: ffffffff8d66d4d0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x131/0x4b0 kernel/fork.c:1581 #1: ffff8880365f1070 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:353 [inline] #1: ffff8880365f1070 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x125/0x1b40 mm/mmap.c:1726 #2: ffff8880339e7670 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:343 [inline] #2: ffff8880339e7670 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x20d/0x1b40 mm/mmap.c:1733 #3: ffff88802fa313c0 (&mapping->i_mmap_rwsem){++++}-{4:4}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:647 #4: ffff8880b8943808 (&s->lock_key#135){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline] #4: ffff8880b8943808 (&s->lock_key#135){+.+.}-{3:3}, at: ___slab_alloc+0x12f/0x1400 mm/slub.c:4516 3 locks held by dhcpcd/5460: 2 locks held by getty/5551: #0: ffff8880340650a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x44f/0x1460 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/5804: 3 locks held by kworker/u8:15/6019: #0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc900052efb80 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc900052efb80 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffffffff8e89b438 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 4 locks held by kworker/u8:16/6163: 2 locks held by kworker/0:10/6213: 5 locks held by kworker/1:11/6459: 2 locks held by kworker/u8:17/6583: 2 locks held by kworker/0:13/7520: 2 locks held by kworker/0:15/7801: #0: ffff8880b883b6d8 (&rq->__lock){-...}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:647 #1: ffff8880b8824688 (psi_seq){-...}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffff8880b8824688 (psi_seq){-...}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 5 locks held by syz.2.785/8059: 1 lock held by syz.3.793/8084: 6 locks held by kworker/u8:18/8103: 4 locks held by syz-executor/8113: #0: ffffffff8e88e320 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x3cc/0x570 net/core/net_namespace.c:577 #1: ffffffff8e5ff040 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x1f5/0x2f0 drivers/infiniband/core/device.c:1215 #2: ffffffff8e5ff280 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x22d/0x2f0 drivers/infiniband/core/device.c:1220 #3: ffff888038c91118 (&device->compat_devs_mutex){+.+.}-{4:4}, at: add_one_compat_dev+0xf0/0x650 drivers/infiniband/core/device.c:979 1 lock held by syz-executor/8116: 4 locks held by syz-executor/8117: #0: ffffffff8e88e320 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x3cc/0x570 net/core/net_namespace.c:577 #1: ffffffff8e5ff040 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x1f5/0x2f0 drivers/infiniband/core/device.c:1215 #2: ffffffff8e5ff280 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x22d/0x2f0 drivers/infiniband/core/device.c:1220 #3: ffff888038c91118 (&device->compat_devs_mutex){+.+.}-{4:4}, at: add_one_compat_dev+0xf0/0x650 drivers/infiniband/core/device.c:979 3 locks held by kworker/u8:19/8132: 4 locks held by syz-executor/8140: 1 lock held by syz-executor/8144: 4 locks held by syz-executor/8148: 2 locks held by syz-executor/8153: 1 lock held by dhcpcd/8155: 2 locks held by kworker/u8:21/8157: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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] __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:346 [inline] watchdog+0xf95/0xfe0 kernel/hung_task.c:515 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 16 Comm: ktimers/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:_raw_spin_unlock_irqrestore+0xc/0x110 kernel/locking/spinlock.c:193 Code: 3d 00 00 cc 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 48 89 e5 41 57 41 56 <41> 54 53 48 83 e4 e0 48 83 ec 60 48 89 f3 49 89 fe 65 48 8b 05 9b RSP: 0000:ffffc90000157a00 EFLAGS: 00000002 RAX: 0000000000000002 RBX: ffffc90000157a68 RCX: ffffffff98bc1403 RDX: 0000000000000001 RSI: 0000000000000a06 RDI: ffff8880b88285e0 RBP: ffffc90000157a10 R08: ffff8880b8828637 R09: 1ffff110171050c6 R10: dffffc0000000000 R11: ffffed10171050c7 R12: 1ffff9200002af4d R13: 0000000000000a06 R14: ffff8880b88285e0 R15: ffffc90000157a60 FS: 0000000000000000(0000) GS:ffff888126d12000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007face9a94028 CR3: 0000000035d80000 CR4: 00000000003526f0 raw_spin_unlock_irqrestore_wake include/linux/sched/wake_q.h:94 [inline] rtlock_slowlock kernel/locking/rtmutex.c:1896 [inline] rtlock_lock kernel/locking/spinlock_rt.c:43 [inline] __rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline] rt_spin_lock+0x16d/0x3e0 kernel/locking/spinlock_rt.c:57 spin_lock include/linux/spinlock_rt.h:44 [inline] hrtimer_cpu_base_lock_expiry kernel/time/hrtimer.c:1376 [inline] hrtimer_run_softirq+0x7c/0x2e0 kernel/time/hrtimer.c:1854 handle_softirqs+0x226/0x6d0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] run_ktimerd+0xcf/0x190 kernel/softirq.c:1138 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246