INFO: task syz-executor.0:1971 blocked for more than 143 seconds. Not tainted 6.8.0-rc4-syzkaller-01071-g4934446297c2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:20984 pid:1971 tgid:1971 ppid:1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0x17d1/0x49f0 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6802 [inline] schedule+0x149/0x260 kernel/sched/core.c:6817 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6874 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a3/0xd70 kernel/locking/mutex.c:752 del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 kernfs_fop_write_iter+0x3a4/0x500 fs/kernfs/file.c:334 call_write_iter include/linux/fs.h:2085 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa81/0xcb0 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7f677347caef RSP: 002b:00007ffe87f706e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f677347caef RDX: 0000000000000001 RSI: 00007ffe87f70730 RDI: 0000000000000005 RBP: 00007f67734ca021 R08: 0000000000000000 R09: 00007ffe87f70537 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001 R13: 00007ffe87f70730 R14: 00007f67740d4620 R15: 0000000000000003 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8e130ae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8e130ae0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8e130ae0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 1 lock held by klogd/4514: #0: ffff8880b943c958 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559 1 lock held by dhcpcd/4739: #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1bc0 net/ipv4/devinet.c:1091 2 locks held by getty/4829: #0: ffff88802f9090a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002efe2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b4/0x1e10 drivers/tty/n_tty.c:2201 3 locks held by kworker/u4:2/5092: #0: ffff88802a2c7938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff88802a2c7938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc9000b8cfd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc9000b8cfd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4179 2 locks held by kworker/u4:7/19153: 5 locks held by kworker/u4:8/22685: #0: ffff8880162f4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff8880162f4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc90003a27d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc90003a27d20 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffffffff8f36a650 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:591 #3: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: cleanup_net+0x6af/0xcc0 net/core/net_namespace.c:627 #4: ffffffff8e136340 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x550 kernel/rcu/tree.c:4064 3 locks held by kworker/0:3/1487: #0: ffff888014c8c938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff888014c8c938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc900041e7d20 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc900041e7d20 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:75 3 locks held by kworker/1:15/1511: #0: ffff888014c8c938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff888014c8c938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc900043ffd20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc900043ffd20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 7 locks held by syz-executor.1/1961: #0: ffff88807d284420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2792 [inline] #0: ffff88807d284420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x233/0xcb0 fs/read_write.c:586 #1: ffff888084d4e088 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325 #2: ffff88802328d100 (kn->active#51){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326 #3: ffffffff8ecb6728 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: new_device_store+0x1b4/0x890 drivers/net/netdevsim/bus.c:166 #4: ffff88808bc9a0e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:990 [inline] #4: ffff88808bc9a0e8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8e/0x520 drivers/base/dd.c:1005 #5: ffff88814d410250 (&devlink->lock_key#28){+.+.}-{3:3}, at: nsim_drv_probe+0xcb/0xb80 drivers/net/netdevsim/dev.c:1534 #6: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3622 4 locks held by syz-executor.4/1967: #0: ffff88807d284420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2792 [inline] #0: ffff88807d284420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x233/0xcb0 fs/read_write.c:586 #1: ffff888097892488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325 #2: ffff88802328d1f8 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326 #3: ffffffff8ecb6728 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor.0/1971: #0: ffff88807d284420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2792 [inline] #0: ffff88807d284420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x233/0xcb0 fs/read_write.c:586 #1: ffff888044a2cc88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325 #2: ffff88802328d1f8 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326 #3: ffffffff8ecb6728 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 1 lock held by syz-executor.2/1973: #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.3/2051: #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.1/2131: #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.0/2140: #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.4/2143: #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.2/2145: #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.3/2148: #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.1/2159: #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.0/2163: #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.4/2170: #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.2/2173: #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.3/2177: #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376bc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc4-syzkaller-01071-g4934446297c2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xfaf/0xff0 kernel/hung_task.c:379 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 31049 Comm: kworker/u4:4 Not tainted 6.8.0-rc4-syzkaller-01071-g4934446297c2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:26 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:67 [inline] RIP: 0010:lockdep_hardirqs_off+0x48/0x110 kernel/locking/lockdep.c:4451 Code: 04 00 0f 84 8d 00 00 00 49 89 fe 65 8b 05 28 7f 9b 74 a9 00 00 f0 00 74 65 83 3d d2 c3 e0 08 00 75 15 48 c7 04 24 00 00 00 00 <9c> 8f 04 24 f7 04 24 00 02 00 00 75 7a 65 8b 05 6c 47 9a 74 85 c0 RSP: 0018:ffffc90014267a08 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffffffff81592006 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8baab600 RDI: ffffffff8bfe7260 RBP: ffffc90014267af0 R08: ffff888091db4343 R09: 1ffff110123b6868 R10: dffffc0000000000 R11: ffffed10123b6869 R12: dffffc0000000000 R13: 1ffff9200284cf50 R14: ffffffff81592006 R15: 0000000000000201 FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c00b459820 CR3: 000000000df32000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_hardirqs_off+0x12/0x40 kernel/trace/trace_preemptirq.c:87 __local_bh_enable_ip+0x106/0x200 kernel/softirq.c:363 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_nc_purge_paths+0x30f/0x3b0 net/batman-adv/network-coding.c:471 batadv_nc_worker+0x328/0x610 net/batman-adv/network-coding.c:720 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242