INFO: task kworker/u4:1:10 blocked for more than 143 seconds. Not tainted 5.15.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:1 state:D stack:25424 pid: 10 ppid: 2 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6287 schedule+0xd3/0x270 kernel/sched/core.c:6366 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6425 __mutex_lock_common kernel/locking/mutex.c:669 [inline] __mutex_lock+0xa34/0x12f0 kernel/locking/mutex.c:729 tc_action_net_exit include/net/act_api.h:155 [inline] gate_exit_net+0x22/0x370 net/sched/act_gate.c:624 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:591 process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Showing all locks held in the system: 4 locks held by kworker/u4:1/10: #0: ffff888015ff2938 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888015ff2938 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888015ff2938 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff888015ff2938 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff888015ff2938 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff888015ff2938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268 #1: ffffc90000cf7db0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 #2: ffffffff8d0d05d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xb00 net/core/net_namespace.c:553 #3: ffffffff8d0e3b68 (rtnl_mutex){+.+.}-{3:3}, at: tc_action_net_exit include/net/act_api.h:155 [inline] #3: ffffffff8d0e3b68 (rtnl_mutex){+.+.}-{3:3}, at: gate_exit_net+0x22/0x370 net/sched/act_gate.c:624 1 lock held by khungtaskd/26: #0: ffffffff8b97fea0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 1 lock held by in:imklog/6404: #0: ffff88807397f9f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 2 locks held by agetty/6498: #0: ffff88807d7b3098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffffc9000122c2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113 3 locks held by kworker/u4:5/8506: #0: ffff8881403a4138 ((wq_completion)cfg80211){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881403a4138 ((wq_completion)cfg80211){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff8881403a4138 ((wq_completion)cfg80211){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff8881403a4138 ((wq_completion)cfg80211){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff8881403a4138 ((wq_completion)cfg80211){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff8881403a4138 ((wq_completion)cfg80211){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268 #1: ffffc90016b8fdb0 ((work_completion)(&(&rdev->dfs_update_channels_wk)->work)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 #2: ffffffff8d0e3b68 (rtnl_mutex){+.+.}-{3:3}, at: cfg80211_dfs_channels_update_work+0x91/0x5f0 net/wireless/mlme.c:842 3 locks held by kworker/1:12/18590: #0: ffff888010c65d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010c65d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888010c65d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff888010c65d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff888010c65d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff888010c65d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268 #1: ffffc90004387db0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 #2: ffffffff8d0e3b68 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x83/0xe10 net/wireless/reg.c:2423 3 locks held by kworker/0:9/22068: #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268 #1: ffffc900061c7db0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 #2: ffffffff8d0e3b68 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xb/0x60 net/core/link_watch.c:251 3 locks held by kworker/0:11/22071: #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268 #1: ffffc900060f7db0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 #2: ffffffff8d0e3b68 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74 3 locks held by kworker/0:13/22073: #0: ffff8881476d5538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881476d5538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff8881476d5538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff8881476d5538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff8881476d5538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff8881476d5538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268 #1: ffffc90006227db0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 #2: ffffffff8d0e3b68 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xa3/0x1340 net/ipv6/addrconf.c:4047 2 locks held by kworker/1:0/26865: 3 locks held by kworker/1:7/28325: #0: ffff8881476d5538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881476d5538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff8881476d5538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff8881476d5538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff8881476d5538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff8881476d5538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268 #1: ffffc9000404fdb0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 #2: ffffffff8d0e3b68 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xa3/0x1340 net/ipv6/addrconf.c:4047 1 lock held by syz-executor.3/29169: #0: ffffffff8d0e3b68 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:684 [inline] #0: ffffffff8d0e3b68 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x180 drivers/net/tun.c:3397 2 locks held by syz-executor.4/29168: #0: ffffffff8d0e3b68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d0e3b68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3be/0xb80 net/core/rtnetlink.c:5569 #1: ffffffff8b989228 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #1: ffffffff8b989228 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4fc/0x620 kernel/rcu/tree_exp.h:837 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 26 Comm: khungtaskd Not tainted 5.15.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xc1d/0xf50 kernel/hung_task.c:295 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 26865 Comm: kworker/1:0 Not tainted 5.15.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events iterate_cleanup_work RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:127 [inline] RIP: 0010:check_preemption_disabled+0x4d/0x140 lib/smp_processor_id.c:19 Code: e3 ff ff ff 7f 31 ff 89 de 0f 1f 44 00 00 85 db 74 11 0f 1f 44 00 00 44 89 e0 5b 5d 41 5c 41 5d 41 5e c3 0f 1f 44 00 00 9c 5b <81> e3 00 02 00 00 31 ff 48 89 de 0f 1f 44 00 00 48 85 db 74 d3 0f RSP: 0018:ffffc9000336fb30 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000046 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffff89e42ba0 R08: 0000000000000001 R09: ffffffff8fcfaa57 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001 R13: ffffffff898bfc40 R14: 00000000ffffffff R15: ffff88803ba4a6a0 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c01131e000 CR3: 000000000b68e000 CR4: 00000000001506e0 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:438 [inline] lock_is_held_type+0xd5/0x140 kernel/locking/lockdep.c:5669 lock_is_held include/linux/lockdep.h:283 [inline] ___might_sleep+0x21/0x2c0 kernel/sched/core.c:9504 get_next_corpse net/netfilter/nf_conntrack_core.c:2253 [inline] nf_ct_iterate_cleanup+0x16d/0x450 net/netfilter/nf_conntrack_core.c:2275 nf_ct_iterate_cleanup_net net/netfilter/nf_conntrack_core.c:2363 [inline] nf_ct_iterate_cleanup_net+0x236/0x400 net/netfilter/nf_conntrack_core.c:2347 iterate_cleanup_work+0x45/0x130 net/netfilter/nf_nat_masquerade.c:216 process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess), 4 bytes skipped: 0: 7f 31 jg 0x33 2: ff 89 de 0f 1f 44 decl 0x441f0fde(%rcx) 8: 00 00 add %al,(%rax) a: 85 db test %ebx,%ebx c: 74 11 je 0x1f e: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 13: 44 89 e0 mov %r12d,%eax 16: 5b pop %rbx 17: 5d pop %rbp 18: 41 5c pop %r12 1a: 41 5d pop %r13 1c: 41 5e pop %r14 1e: c3 retq 1f: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 24: 9c pushfq 25: 5b pop %rbx * 26: 81 e3 00 02 00 00 and $0x200,%ebx <-- trapping instruction 2c: 31 ff xor %edi,%edi 2e: 48 89 de mov %rbx,%rsi 31: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 36: 48 85 db test %rbx,%rbx 39: 74 d3 je 0xe 3b: 0f .byte 0xf