INFO: task syz.0.5335:1733 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.0.5335 state:D stack:27000 pid:1733 tgid:1731 ppid:23782 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383 rwsem_down_read_slowpath+0x6ba/0x920 kernel/locking/rwsem.c:1114 __down_read_common kernel/locking/rwsem.c:1291 [inline] __down_read kernel/locking/rwsem.c:1304 [inline] down_read+0x9c/0x330 kernel/locking/rwsem.c:1576 __super_lock fs/super.c:60 [inline] super_lock+0x2d6/0x3d0 fs/super.c:122 __iterate_supers+0x120/0x240 fs/super.c:866 quota_sync_all fs/quota/quota.c:69 [inline] __do_sys_quotactl fs/quota/quota.c:938 [inline] __se_sys_quotactl+0x3a0/0x9a0 fs/quota/quota.c:917 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: 0033:0x7f8de1b9de59 RSP: 002b:00007f8de29e8028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 00007f8de1e25fa0 RCX: 00007f8de1b9de59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000102 RBP: 00007f8de1c33e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8de1e26038 R14: 00007f8de1e25fa0 R15: 00007ffd2c7c9458 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 5 locks held by kworker/u8:6/145: #0: ffff8880b873b160 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:667 #1: ffff8880b8724440 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x57/0x7d0 kernel/sched/psi.c:933 #2: ffff8880b8726058 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline] #2: ffff8880b8726058 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1a9/0xed0 kernel/time/timer.c:1085 #3: ffffffff9a9aedb0 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0xb7/0x420 lib/debugobjects.c:873 #4: ffff8880b8726058 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline] #4: ffff8880b8726058 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1a9/0xed0 kernel/time/timer.c:1085 1 lock held by dhcpcd/5280: 2 locks held by getty/5374: #0: ffff8880351e10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211 3 locks held by kworker/u8:11/6110: #0: ffff888031604940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff888031604940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc90005117c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc90005117c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff9002ca80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff9002ca80 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x116/0x15c0 net/ipv6/addrconf.c:4229 2 locks held by syz-executor/32732: 7 locks held by kworker/u8:1/731: #0: ffff88801c28e140 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88801c28e140 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc9000520fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc9000520fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff9001dec8 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf5/0x810 net/core/net_namespace.c:673 #3: ffff888034b9d128 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline] #3: ffff888034b9d128 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:124 [inline] #3: ffff888034b9d128 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x129/0x420 net/devlink/core.c:557 #4: ffff888033662258 (&devlink->lock_key#69){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:292 [inline] #4: ffff888033662258 (&devlink->lock_key#69){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:125 [inline] #4: ffff888033662258 (&devlink->lock_key#69){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x142/0x420 net/devlink/core.c:557 #5: ffffffff9002ca80 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0x173/0x800 drivers/net/netdevsim/netdev.c:1191 #6: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #6: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961 3 locks held by kworker/u8:4/989: #0: ffff88801b064140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88801b064140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc90004c1fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc90004c1fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff9002ca80 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313 1 lock held by syz.0.5335/1733: #0: ffff8880511a20d8 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff8880511a20d8 (&type->s_umount_key#54){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz-executor/2110: #0: ffffffff9002ca80 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:641 [inline] #0: ffffffff9002ca80 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3506 2 locks held by syz-executor/2246: #0: ffffffff9057c830 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] ffffffff9057c830 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] ffffffff9057c830 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff9002ca80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff9002ca80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff9002ca80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a3/0x1bd0 net/core/rtnetlink.c:4158 2 locks held by syz-executor/2402: #0: ffffffff9001dec8 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4e2/0x720 net/core/net_namespace.c:575 #1: ffffffff9002ca80 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x2d5/0x820 net/ipv4/ip_tunnel.c:1149 2 locks held by syz.4.5418/2456: #0: ffffffff9009d2e8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff9002ca80 (rtnl_mutex){+.+.}-{4:4}, at: nl80211_pre_doit+0x5e/0x890 net/wireless/nl80211.c:19287 2 locks held by syz.8.5419/2464: #0: ffffffff9001dec8 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4e2/0x720 net/core/net_namespace.c:575 #1: ffffffff9002ca80 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x8b/0x290 net/ipv4/nexthop.c:4017 1 lock held by syz-executor/2463: #0: ffffffff9002ca80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff9002ca80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff9002ca80 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a3/0x1bd0 net/core/rtnetlink.c:4158 1 lock held by syz.3.5421/2478: #0: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #0: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 101 PID: 5280 Comm: dhcpcd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026 RIP: 0010:entry_SYSRETQ_unsafe_stack+0xa/0xd Code: 89 c7 eb 08 48 89 c7 48 0f ba ef 3f 48 81 cf 00 08 00 00 48 81 cf 00 10 00 00 0f 22 df 58 5f 5c 0f 01 f8 0f 00 2d 77 fe ff ff <48> 0f 07 cc 90 90 90 56 48 8b 74 24 08 48 89 7c 24 08 52 51 50 41 RSP: 0018:00007ffed3107cc8 EFLAGS: 00000042 RAX: 00000000000014a0 RBX: 00007ffed3107ce0 RCX: 00007f6ccd040917 RDX: 00007ffed3108110 RSI: 000055d6bceec168 RDI: 0000000000000007 RBP: 000055d6bceec168 R08: 0000000000000030 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000217 R12: 00007ffed3108110 R13: 000055d6da32dec0 R14: 000055d6da4fb2b0 R15: 000055d6da322360 FS: 00007f6cccf66780(0000) GS:ffff888125056000(0000) knlGS:ffff888125056000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa4d93ff000 CR3: 000000007b5cd000 CR4: 0000000000350ef0 Call Trace: