INFO: task syz.2.21:6059 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.21 state:D stack:24576 pid:6059 tgid:6010 ppid:5797 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0x1553/0x5240 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7289 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760 rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244 inode_lock_nested include/linux/fs.h:1073 [inline] lock_rename fs/namei.c:3762 [inline] __start_renaming+0x148/0x410 fs/namei.c:3858 filename_renameat2+0x38c/0x9c0 fs/namei.c:6125 __do_sys_renameat2 fs/namei.c:6179 [inline] __se_sys_renameat2+0x5a/0x2c0 fs/namei.c:6174 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3028c2c819 RSP: 002b:00007f3026e65028 EFLAGS: 00000246 ORIG_RAX: 000000000000013c RAX: ffffffffffffffda RBX: 00007f3028ea6090 RCX: 00007f3028c2c819 RDX: ffffffffffffff9c RSI: 0000200000000440 RDI: ffffffffffffff9c RBP: 00007f3028cc2c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000200000000140 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3028ea6128 R14: 00007f3028ea6090 R15: 00007ffd52715138 Showing all locks held in the system: 6 locks held by kworker/u8:0/12: #0: ffff88801aee1138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #0: ffff88801aee1138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359 #1: ffffc90000117c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline] #1: ffffc90000117c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359 #2: ffffffff8f14e800 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:675 #3: ffff88805eda3160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #3: ffff88805eda3160 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff88805eda3160 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x11b/0x3f0 net/devlink/core.c:504 #4: ffff88803cf58300 (&devlink->lock_key#5){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:274 [inline] #4: ffff88803cf58300 (&devlink->lock_key#5){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #4: ffff88803cf58300 (&devlink->lock_key#5){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x12d/0x3f0 net/devlink/core.c:504 #5: ffffffff8f15cfb8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0xed/0x680 drivers/net/netdevsim/netdev.c:1180 1 lock held by khungtaskd/38: #0: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/u8:2/43: 2 locks held by kworker/u8:3/57: 2 locks held by kworker/u8:6/152: #0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359 #1: ffffc90003a37c40 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline] #1: ffffc90003a37c40 ((reaper_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359 4 locks held by kworker/u8:11/1210: #0: ffff88801aee4138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #0: ffff88801aee4138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359 #1: ffffc900059dfc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline] #1: ffffc900059dfc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359 #2: ffff88803a73c0d0 (&type->s_umount_key#86){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565 #3: ffff88805e8cbc68 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108 2 locks held by kworker/u8:14/4542: #0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359 #1: ffffc90010dffc40 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline] #1: ffffc90010dffc40 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359 2 locks held by getty/5553: #0: ffff888032bb40a0 (&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+0x462/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by udevd/5790: 1 lock held by udevd/6006: 4 locks held by syz.2.21/6011: 2 locks held by syz.2.21/6059: #0: ffff88803a73c480 (sb_writers#22){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 #1: ffff88805e8cc038 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline] #1: ffff88805e8cc038 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: lock_rename fs/namei.c:3762 [inline] #1: ffff88805e8cc038 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: __start_renaming+0x148/0x410 fs/namei.c:3858 2 locks held by syz-executor/7838: #0: ffffffff8f14e800 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4f7/0x730 net/core/net_namespace.c:577 #1: ffffffff8f15cfb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock_killable include/linux/rtnetlink.h:145 [inline] #1: ffffffff8f15cfb8 (rtnl_mutex){+.+.}-{4:4}, at: register_netdev+0x18/0x60 net/core/dev.c:11554 2 locks held by syz.3.295/7862: ============================================= 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 03/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [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+0xfd9/0x1030 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 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: 43 Comm: kworker/u8:2 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:58 [inline] RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:409 [inline] RIP: 0010:deref_stack_reg+0xa5/0x230 arch/x86/kernel/unwind_orc.c:419 Code: 00 00 00 fc ff df 4c 89 74 24 08 4d 8b 77 10 4c 89 fd 48 c1 ed 03 0f b6 44 35 00 84 c0 0f 85 3c 01 00 00 41 83 3f 00 0f 95 c0 <4c> 39 c3 0f 96 c1 20 c1 4d 39 c6 0f 97 c0 20 c8 3c 01 75 18 49 8d RSP: 0018:ffffc90000b57080 EFLAGS: 00000202 RAX: 0000000000000001 RBX: ffffc90000b50000 RCX: 0000000000000000 RDX: ffffc90000b571e8 RSI: dffffc0000000000 RDI: ffffc90000b571a8 RBP: 1ffff9200016ae35 R08: ffffc90000b57ce8 R09: 0000000000000000 R10: ffffc90000b571f8 R11: fffff5200016ae41 R12: 1ffff9200016ae36 R13: 1ffff9200016ae37 R14: ffffc90000b58000 R15: ffffc90000b571a8 FS: 0000000000000000(0000) GS:ffff888126335000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f737e37f000 CR3: 000000003eaee000 CR4: 00000000003526f0 Call Trace: unwind_next_frame+0x18c6/0x23c0 arch/x86/kernel/unwind_orc.c:-1 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 save_stack+0x124/0x230 mm/page_owner.c:165 __set_page_owner+0x8d/0x4b0 mm/page_owner.c:341 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x231/0x280 mm/page_alloc.c:1889 prep_new_page mm/page_alloc.c:1897 [inline] get_page_from_freelist+0x28bb/0x2950 mm/page_alloc.c:3962 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250 alloc_slab_page mm/slub.c:3292 [inline] allocate_slab+0x77/0x660 mm/slub.c:3481 new_slab mm/slub.c:3539 [inline] refill_objects+0x334/0x3c0 mm/slub.c:7175 refill_sheaf mm/slub.c:2812 [inline] __pcs_replace_empty_main+0x35c/0x710 mm/slub.c:4615 alloc_from_pcs mm/slub.c:4717 [inline] slab_alloc_node mm/slub.c:4851 [inline] kmem_cache_alloc_node_noprof+0x4f4/0x6e0 mm/slub.c:4918 __alloc_skb+0x1d0/0x7d0 net/core/skbuff.c:702 alloc_skb include/linux/skbuff.h:1383 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:819 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:876 [inline] nsim_dev_trap_report_work+0x29f/0xbc0 drivers/net/netdevsim/dev.c:922 process_one_work kernel/workqueue.c:3276 [inline] process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3440 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245