INFO: task kworker/1:0:25 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-12113-ge7ed34365879 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:0 state:D stack:21008 pid:25 tgid:25 ppid:2 flags:0x00004000 Workqueue: events ovs_dp_masks_rebalance Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752 ovs_lock net/openvswitch/datapath.c:108 [inline] ovs_dp_masks_rebalance+0x2f/0xe0 net/openvswitch/datapath.c:2527 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task kworker/1:1:51 blocked for more than 144 seconds. Not tainted 6.11.0-syzkaller-12113-ge7ed34365879 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:1 state:D stack:21680 pid:51 tgid:51 ppid:2 flags:0x00004000 Workqueue: events ovs_dp_masks_rebalance Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752 ovs_lock net/openvswitch/datapath.c:108 [inline] ovs_dp_masks_rebalance+0x2f/0xe0 net/openvswitch/datapath.c:2527 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task kworker/1:7:5359 blocked for more than 145 seconds. Not tainted 6.11.0-syzkaller-12113-ge7ed34365879 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:7 state:D stack:21104 pid:5359 tgid:5359 ppid:2 flags:0x00004000 Workqueue: events ovs_dp_masks_rebalance Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752 ovs_lock net/openvswitch/datapath.c:108 [inline] ovs_dp_masks_rebalance+0x2f/0xe0 net/openvswitch/datapath.c:2527 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 3 locks held by kworker/1:0/25: #0: ffff88801ac78948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac78948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc900001f7d00 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900001f7d00 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff90004f68 (ovs_mutex){+.+.}-{3:3}, at: ovs_lock net/openvswitch/datapath.c:108 [inline] #2: ffffffff90004f68 (ovs_mutex){+.+.}-{3:3}, at: ovs_dp_masks_rebalance+0x2f/0xe0 net/openvswitch/datapath.c:2527 1 lock held by khungtaskd/30: #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720 4 locks held by kworker/u8:2/35: 3 locks held by kworker/1:1/51: #0: ffff88801ac78948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac78948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000bb7d00 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000bb7d00 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff90004f68 (ovs_mutex){+.+.}-{3:3}, at: ovs_lock net/openvswitch/datapath.c:108 [inline] #2: ffffffff90004f68 (ovs_mutex){+.+.}-{3:3}, at: ovs_dp_masks_rebalance+0x2f/0xe0 net/openvswitch/datapath.c:2527 3 locks held by kworker/u8:4/68: #0: ffff88801ac81148 ( (wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] (wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc900015f7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900015f7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 2 locks held by getty/4986: #0: ffff88802e7ef0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by syz-executor/5240: 3 locks held by kworker/1:4/5296: 7 locks held by kworker/1:6/5358: 3 locks held by kworker/1:7/5359: #0: ffff88801ac78948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac78948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc9000312fd00 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000312fd00 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff90004f68 (ovs_mutex){+.+.}-{3:3}, at: ovs_lock net/openvswitch/datapath.c:108 [inline] #2: ffffffff90004f68 (ovs_mutex){+.+.}-{3:3}, at: ovs_dp_masks_rebalance+0x2f/0xe0 net/openvswitch/datapath.c:2527 1 lock held by syz.3.1910/9470: #0: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 2 locks held by syz.4.1920/9494: #0: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 #1: ffffffff8e7d1dd0 (cpu_hotplug_lock){++++}-{0:0}, at: flush_all_backlogs net/core/dev.c:6021 [inline] #1: ffffffff8e7d1dd0 (cpu_hotplug_lock){++++}-{0:0}, at: unregister_netdevice_many_notify+0x5ea/0x1da0 net/core/dev.c:11380 1 lock held by syz.1.1927/9506: #0: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 1 lock held by syz.2.1939/9531: #0: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 1 lock held by syz.0.1947/9547: #0: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 1 lock held by syz.5.1959/9577: #0: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 2 locks held by syz-executor/9621: #0: ffffffff8fcc4c10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:490 #1: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: wg_netns_pre_exit+0x1f/0x1e0 drivers/net/wireguard/device.c:414 2 locks held by syz-executor/9627: #0: ffffffff8fcc4c10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:490 #1: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_init_net+0x20e/0x720 net/ipv4/ip_tunnel.c:1159 2 locks held by syz-executor/9630: #0: ffffffff8fcc4c10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:490 #1: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_init_net+0x20e/0x720 net/ipv4/ip_tunnel.c:1159 2 locks held by syz-executor/9633: #0: ffffffff8fcc4c10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:490 #1: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_init_net+0x20e/0x720 net/ipv4/ip_tunnel.c:1159 2 locks held by syz-executor/9636: #0: ffffffff8fcc4c10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:490 #1: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_init_net+0x20e/0x720 net/ipv4/ip_tunnel.c:1159 2 locks held by syz-executor/9639: #0: ffffffff8fcc4c10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:490 #1: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_init_net+0x20e/0x720 net/ipv4/ip_tunnel.c:1159 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-12113-ge7ed34365879 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5358 Comm: kworker/1:6 Not tainted 6.11.0-syzkaller-12113-ge7ed34365879 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events nsim_dev_trap_report_work RIP: 0010:rcu_lockdep_current_cpu_online+0x32/0x120 kernel/rcu/tree.c:4773 Code: 53 65 8b 0d 88 b6 88 7e b0 01 f7 c1 00 00 f0 00 0f 85 d5 00 00 00 83 3d cb c5 a1 0e 00 0f 84 c8 00 00 00 65 ff 05 66 b6 88 7e a9 42 4a 0a 89 c3 83 f8 08 0f 83 c6 00 00 00 49 be 00 00 00 00 RSP: 0018:ffffc90000a17fd0 EFLAGS: 00000286 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000080000102 RDX: ffff888027823c00 RSI: ffffffff8c60f840 RDI: ffffffff8c60f800 RBP: ffff8880321840b8 R08: ffffffff8997fb86 R09: ffffc90000a18330 R10: ffffc90000a18320 R11: fffff52000143032 R12: ffff888057c84000 R13: ffff8880321840cf R14: 1ffff11006430819 R15: 1ffff11006430817 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe6d74656c0 CR3: 000000000e734000 CR4: 0000000000350ef0 Call Trace: rcu_read_lock_held_common kernel/rcu/update.c:113 [inline] rcu_read_lock_held+0x1e/0x50 kernel/rcu/update.c:349 __in6_dev_get include/net/addrconf.h:330 [inline] ip6_ignore_linkdown include/net/addrconf.h:421 [inline] find_match+0xf9/0xc10 net/ipv6/route.c:744 __find_rr_leaf+0x275/0x8e0 net/ipv6/route.c:832 find_rr_leaf net/ipv6/route.c:853 [inline] rt6_select net/ipv6/route.c:897 [inline] fib6_table_lookup+0x413/0xbb0 net/ipv6/route.c:2195 ip6_pol_route+0x273/0x15d0 net/ipv6/route.c:2231 pol_lookup_func include/net/ip6_fib.h:616 [inline] fib6_rule_lookup+0x58c/0x790 net/ipv6/fib6_rules.c:117 ip6_route_input_lookup net/ipv6/route.c:2300 [inline] ip6_route_input+0x859/0xd90 net/ipv6/route.c:2596 ip6_rcv_finish+0x144/0x180 net/ipv6/ip6_input.c:77 NF_HOOK+0x3a6/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5662 [inline] __netif_receive_skb+0x1ea/0x650 net/core/dev.c:5775 process_backlog+0x662/0x15b0 net/core/dev.c:6107 __napi_poll+0xcd/0x490 net/core/dev.c:6771 napi_poll net/core/dev.c:6840 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6962 handle_softirqs+0x2c7/0x980 kernel/softirq.c:554 do_softirq+0x11b/0x1e0 kernel/softirq.c:455 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382 spin_unlock_bh include/linux/spinlock.h:396 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline] nsim_dev_trap_report_work+0x75d/0xaa0 drivers/net/netdevsim/dev.c:850 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244