INFO: task syz-executor.5:18546 blocked for more than 143 seconds. Not tainted 6.3.0-rc7-syzkaller-02223-gfbc1449d385d #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:24648 pid:18546 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5307 [inline] __schedule+0xc91/0x5770 kernel/sched/core.c:6625 schedule+0xde/0x1a0 kernel/sched/core.c:6701 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6760 rwsem_down_write_slowpath+0x3e2/0x1220 kernel/locking/rwsem.c:1178 __down_write_common kernel/locking/rwsem.c:1306 [inline] __down_write kernel/locking/rwsem.c:1315 [inline] down_write+0x1d2/0x200 kernel/locking/rwsem.c:1574 unregister_netdevice_notifier+0x22/0x180 net/core/dev.c:1757 devlink_free+0x2cb/0x460 net/devlink/core.c:269 nsim_drv_remove+0x158/0x1d0 drivers/net/netdevsim/dev.c:1687 device_remove+0xc8/0x170 drivers/base/dd.c:540 __device_release_driver drivers/base/dd.c:1240 [inline] device_release_driver_internal+0x443/0x610 drivers/base/dd.c:1263 bus_remove_device+0x22c/0x420 drivers/base/bus.c:574 device_del+0x48a/0xb80 drivers/base/core.c:3775 device_unregister+0x1e/0xc0 drivers/base/core.c:3805 nsim_bus_dev_del drivers/net/netdevsim/bus.c:310 [inline] del_device_store+0x34e/0x4a0 drivers/net/netdevsim/bus.c:219 bus_attr_store+0x76/0xa0 drivers/base/bus.c:170 sysfs_kf_write+0x114/0x170 fs/sysfs/file.c:136 kernfs_fop_write_iter+0x3f1/0x600 fs/kernfs/file.c:334 call_write_iter include/linux/fs.h:1851 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x9f6/0xe20 fs/read_write.c:584 ksys_write+0x12b/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f942003deef RSP: 002b:00007ffd3c1f4420 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f942003deef RDX: 0000000000000001 RSI: 00007ffd3c1f4470 RDI: 0000000000000005 RBP: 0000000000000005 R08: 0000000000000000 R09: 00007ffd3c1f43c0 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f94200e78b6 R13: 00007ffd3c1f4470 R14: 0000000000000000 R15: 00007ffd3c1f4b40 Showing all locks held in the system: 6 locks held by kworker/u4:1/11: #0: ffff8880b993c298 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2f/0x120 kernel/sched/core.c:539 #1: ffff88802bb653f0 (&mm->cid_lock){....}-{2:2}, at: mm_cid_get kernel/sched/sched.h:3280 [inline] #1: ffff88802bb653f0 (&mm->cid_lock){....}-{2:2}, at: switch_mm_cid kernel/sched/sched.h:3302 [inline] #1: ffff88802bb653f0 (&mm->cid_lock){....}-{2:2}, at: prepare_task_switch kernel/sched/core.c:5117 [inline] #1: ffff88802bb653f0 (&mm->cid_lock){....}-{2:2}, at: context_switch kernel/sched/core.c:5258 [inline] #1: ffff88802bb653f0 (&mm->cid_lock){....}-{2:2}, at: __schedule+0x2802/0x5770 kernel/sched/core.c:6625 #2: ffff888075f2cd40 (&wdev->mtx){+.+.}-{3:3}, at: sdata_lock net/mac80211/ieee80211_i.h:1129 [inline] #2: ffff888075f2cd40 (&wdev->mtx){+.+.}-{3:3}, at: ieee80211_ibss_work+0x94/0x14a0 net/mac80211/ibss.c:1680 #3: ffffffff8c7955c0 (rcu_read_lock){....}-{1:2}, at: sdata_assert_lock net/mac80211/ieee80211_i.h:1146 [inline] #3: ffffffff8c7955c0 (rcu_read_lock){....}-{1:2}, at: ieee80211_sta_active_ibss+0x86/0x390 net/mac80211/ibss.c:652 #4: ffff8880b9929478 (krc.lock){..-.}-{2:2}, at: krc_this_cpu_lock kernel/rcu/tree.c:2856 [inline] #4: ffff8880b9929478 (krc.lock){..-.}-{2:2}, at: add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3243 [inline] #4: ffff8880b9929478 (krc.lock){..-.}-{2:2}, at: kvfree_call_rcu+0xd7/0xad0 kernel/rcu/tree.c:3328 #5: ffffffff8c7955c0 (rcu_read_lock){....}-{1:2}, at: __queue_work+0xca/0x1120 kernel/workqueue.c:1444 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8c794a70 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:510 1 lock held by rcu_tasks_trace/13: #0: ffffffff8c794770 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:510 1 lock held by khungtaskd/28: #0: ffffffff8c7955c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x340 kernel/locking/lockdep.c:6495 2 locks held by getty/4757: #0: ffff88802bb3a098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x26/0x80 drivers/tty/tty_ldisc.c:244 #1: ffffc900015a02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xef4/0x13e0 drivers/tty/n_tty.c:2177 2 locks held by kworker/u4:9/6568: 4 locks held by kworker/u4:13/12323: 6 locks held by syz-executor.5/18546: #0: ffff88802bd82460 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12b/0x250 fs/read_write.c:637 #1: ffff888024cd9c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x285/0x600 fs/kernfs/file.c:325 #2: ffff888146eff3a8 (kn->active#51){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2a9/0x600 fs/kernfs/file.c:326 #3: ffffffff8d7e65a8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xc9/0x4a0 drivers/net/netdevsim/bus.c:209 #4: ffff8880486c70e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:832 [inline] #4: ffff8880486c70e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1063 [inline] #4: ffff8880486c70e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa4/0x610 drivers/base/dd.c:1260 #5: ffffffff8e0e7d10 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x22/0x180 net/core/dev.c:1757 1 lock held by syz-executor.5/18656: #0: ffffffff8e0e7d10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4cb/0x8e0 net/core/net_namespace.c:486 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.3.0-rc7-syzkaller-02223-gfbc1449d385d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 nmi_cpu_backtrace+0x29c/0x350 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x2a4/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xe16/0x1090 kernel/hung_task.c:379 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 12323 Comm: kworker/u4:13 Not tainted 6.3.0-rc7-syzkaller-02223-gfbc1449d385d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Workqueue: netns cleanup_net RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x8/0x20 kernel/kcov.c:304 Code: 00 00 f3 0f 1e fa 48 8b 0c 24 0f b7 d6 0f b7 f7 bf 03 00 00 00 e9 b8 fe ff ff 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 48 8b 0c 24 <89> f2 89 fe bf 05 00 00 00 e9 9a fe ff ff 66 2e 0f 1f 84 00 00 00 RSP: 0018:ffffc9000317fab0 EFLAGS: 00000202 RAX: 1ffff11003106efa RBX: ffff8880188377d0 RCX: ffffffff88473e27 RDX: ffff888018800000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: dffffc0000000000 R08: 0000000000000004 R09: 0000000000006efa R10: 0000000000040000 R11: 0000000000000000 R12: ffffc9000317fb90 R13: 0000000000006efa R14: 0000000000000001 R15: 0000000000009c00 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c006ac4eb8 CR3: 000000000c571000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: get_next_corpse net/netfilter/nf_conntrack_core.c:2369 [inline] nf_ct_iterate_cleanup+0xd7/0x500 net/netfilter/nf_conntrack_core.c:2420 nf_ct_iterate_cleanup_net+0xdb/0x110 net/netfilter/nf_conntrack_core.c:2441 nf_conntrack_cleanup_net_list+0x1cc/0x5d0 net/netfilter/nf_conntrack_core.c:2554 ops_exit_list+0x125/0x170 net/core/net_namespace.c:174 cleanup_net+0x4ee/0xb10 net/core/net_namespace.c:613 process_one_work+0x991/0x15c0 kernel/workqueue.c:2390 worker_thread+0x669/0x1090 kernel/workqueue.c:2537 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308