INFO: task syz-executor.4:9217 blocked for more than 143 seconds. Not tainted 6.3.0-rc5-syzkaller-01273-g490fde262f17 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:24984 pid:9217 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+0x9ed/0xe10 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: 0033:0x7f733c63deef RSP: 002b:00007ffd177e5010 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f733c63deef RDX: 0000000000000001 RSI: 00007ffd177e5060 RDI: 0000000000000005 RBP: 0000000000000005 R08: 0000000000000000 R09: 00007ffd177e4fb0 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f733c6e78b6 R13: 00007ffd177e5060 R14: 0000000000000000 R15: 00007ffd177e5730 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8c794a30 (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: ffffffff8c794730 (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: ffffffff8c795580 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x340 kernel/locking/lockdep.c:6495 2 locks held by syslogd/4424: #0: ffff8880b983c298 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2f/0x120 kernel/sched/core.c:539 #1: ffff88807e9db830 (&mm->cid_lock){....}-{2:2}, at: mm_cid_put kernel/sched/sched.h:3270 [inline] #1: ffff88807e9db830 (&mm->cid_lock){....}-{2:2}, at: mm_cid_put kernel/sched/sched.h:3265 [inline] #1: ffff88807e9db830 (&mm->cid_lock){....}-{2:2}, at: switch_mm_cid kernel/sched/sched.h:3298 [inline] #1: ffff88807e9db830 (&mm->cid_lock){....}-{2:2}, at: prepare_task_switch kernel/sched/core.c:5117 [inline] #1: ffff88807e9db830 (&mm->cid_lock){....}-{2:2}, at: context_switch kernel/sched/core.c:5258 [inline] #1: ffff88807e9db830 (&mm->cid_lock){....}-{2:2}, at: __schedule+0x26a3/0x5770 kernel/sched/core.c:6625 2 locks held by getty/4755: #0: ffff88814a0fb098 (&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 5 locks held by kworker/u4:16/27831: #0: ffff888016617138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888016617138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888016617138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1324 [inline] #0: ffff888016617138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:639 [inline] #0: ffff888016617138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:666 [inline] #0: ffff888016617138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x87a/0x15c0 kernel/workqueue.c:2361 #1: ffffc90015237da8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8ae/0x15c0 kernel/workqueue.c:2365 #2: ffffffff8e0e7f90 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9f/0xb10 net/core/net_namespace.c:575 #3: ffff88802b5513e8 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_destruct+0x14f/0x400 drivers/net/wireguard/device.c:249 #4: ffffffff8c7a0878 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:325 [inline] #4: ffffffff8c7a0878 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3e8/0x770 kernel/rcu/tree_exp.h:989 3 locks held by kworker/u4:6/24771: #0: ffff8880b983c298 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2f/0x120 kernel/sched/core.c:539 #1: ffffc900191dfda8 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x15c0 kernel/workqueue.c:2365 #2: ffff8880b9829698 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x5a/0x1f0 kernel/time/timer.c:999 2 locks held by kworker/0:0/19886: #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1324 [inline] #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:639 [inline] #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:666 [inline] #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x87a/0x15c0 kernel/workqueue.c:2361 #1: ffffc90039bcfda8 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x15c0 kernel/workqueue.c:2365 6 locks held by syz-executor.4/9217: #0: ffff88802c0a2460 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12b/0x250 fs/read_write.c:637 #1: ffff8882105a0488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x285/0x600 fs/kernfs/file.c:325 #2: ffff888146fdb830 (kn->active#51){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2a9/0x600 fs/kernfs/file.c:326 #3: ffffffff8d7e6ca8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xc9/0x4a0 drivers/net/netdevsim/bus.c:209 #4: ffff8880475760e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:832 [inline] #4: ffff8880475760e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1063 [inline] #4: ffff8880475760e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa4/0x610 drivers/base/dd.c:1260 #5: ffffffff8e0e7f90 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x22/0x180 net/core/dev.c:1757 1 lock held by syz-executor.4/9401: #0: ffffffff8e0e7f90 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4cb/0x8e0 net/core/net_namespace.c:486 2 locks held by dhcpcd/9416: #0: ffff88808ae63810 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #0: ffff88808ae63810 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release+0x86/0x290 net/socket.c:652 #1: ffffffff8c7a0878 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:293 [inline] #1: ffffffff8c7a0878 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x64a/0x770 kernel/rcu/tree_exp.h:989 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.3.0-rc5-syzkaller-01273-g490fde262f17 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023 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: 24771 Comm: kworker/u4:6 Not tainted 6.3.0-rc5-syzkaller-01273-g490fde262f17 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023 Workqueue: bat_events batadv_nc_worker RIP: 0010:rcu_is_watching+0x7c/0xb0 kernel/rcu/tree.c:695 Code: 89 da 48 c1 ea 03 0f b6 14 02 48 89 d8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 1c 8b 03 c1 e8 02 83 e0 01 65 ff 0d 0c a3 97 7e <74> 03 5b 5d c3 e8 aa 70 94 ff 5b 5d c3 48 89 df e8 7f 0b 68 00 eb RSP: 0018:ffffc900191dfc70 EFLAGS: 00000286 RAX: 0000000000000001 RBX: ffff8880b9836ca8 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff8c1079c0 RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffc900191dfda8 R13: 0000000000000000 R14: dffffc0000000000 R15: 00000000000003d8 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055a6b5ca9680 CR3: 000000002bdd4000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock include/linux/rcupdate.h:774 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xbc1/0xfe0 net/batman-adv/network-coding.c:719 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