INFO: task syz.1.105:6562 blocked for more than 143 seconds. Tainted: G W 6.17.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.105 state:D stack:29224 pid:6562 tgid:6555 ppid:5842 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7339 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760 rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244 inode_lock_nested include/linux/fs.h:914 [inline] do_unlinkat+0x1c7/0x570 fs/namei.c:4637 __do_sys_unlinkat fs/namei.c:4691 [inline] __se_sys_unlinkat fs/namei.c:4684 [inline] __x64_sys_unlinkat+0xd3/0xf0 fs/namei.c:4684 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f70432febe9 RSP: 002b:00007f704153d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 00007f7043526090 RCX: 00007f70432febe9 RDX: 0000000000000000 RSI: 0000200000000b40 RDI: ffffffffffffff9c RBP: 00007f7043381e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7043526128 R14: 00007f7043526090 R15: 00007ffc005c4578 Showing all locks held in the system: 1 lock held by khungtaskd/39: #0: ffffffff8d9a8b80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d9a8b80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8d9a8b80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:3/57: #0: ffff8881404ba138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff8881404ba138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9000123fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000123fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffff88805e1440d0 (&type->s_umount_key#77){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 #3: ffff88803de69f58 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102 3 locks held by kworker/u8:6/1113: 3 locks held by kworker/u8:9/3176: #0: ffff88802fff7138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88802fff7138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9000d3f7bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000d3f7bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8ecd13b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8ecd13b8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x119/0x15a0 net/ipv6/addrconf.c:4194 6 locks held by kworker/u8:12/3865: #0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9000e217bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000e217bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8ecc4500 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:658 #3: ffff88805c6c20d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #3: ffff88805c6c20d8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff88805c6c20d8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x10a/0x3d0 net/devlink/core.c:506 #4: ffff888027bf7300 (&devlink->lock_key#14){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline] #4: ffff888027bf7300 (&devlink->lock_key#14){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #4: ffff888027bf7300 (&devlink->lock_key#14){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x11c/0x3d0 net/devlink/core.c:506 #5: ffffffff8ecd13b8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0xe5/0x670 drivers/net/netdevsim/netdev.c:1131 1 lock held by dhcpcd/5498: #0: ffffffff8ecd13b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8ecd13b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8ecd13b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056 2 locks held by getty/5597: #0: ffff88823bf840a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1410 drivers/tty/n_tty.c:2222 4 locks held by syz.1.105/6556: 2 locks held by syz.1.105/6562: #0: ffff88805e144488 (sb_writers#20){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557 #1: ffff88803de6a328 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline] #1: ffff88803de6a328 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: do_unlinkat+0x1c7/0x570 fs/namei.c:4637 4 locks held by syz-executor/7074: #0: ffff888033d86488 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3107 [inline] #0: ffff888033d86488 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x217/0xb40 fs/read_write.c:682 #1: ffff8880289f8c78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e1/0x4f0 fs/kernfs/file.c:325 #2: ffff888144b7e1e8 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x204/0x4f0 fs/kernfs/file.c:326 #3: ffffffff8e5419d8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x12c/0x6f0 drivers/net/netdevsim/bus.c:184 4 locks held by syz-executor/7085: #0: ffff888033d86488 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3107 [inline] #0: ffff888033d86488 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x217/0xb40 fs/read_write.c:682 #1: ffff88805d2e1078 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e1/0x4f0 fs/kernfs/file.c:325 #2: ffff888144b7e1e8 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x204/0x4f0 fs/kernfs/file.c:326 #3: ffffffff8e5419d8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x12c/0x6f0 drivers/net/netdevsim/bus.c:184 4 locks held by syz-executor/7087: #0: ffff888033d86488 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3107 [inline] #0: ffff888033d86488 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x217/0xb40 fs/read_write.c:682 #1: ffff888026ed7c78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e1/0x4f0 fs/kernfs/file.c:325 #2: ffff888144b7e2d8 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x204/0x4f0 fs/kernfs/file.c:326 #3: ffffffff8e5419d8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:234 7 locks held by syz-executor/7090: #0: ffff888033d86488 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3107 [inline] #0: ffff888033d86488 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x217/0xb40 fs/read_write.c:682 #1: ffff88805d1d1078 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e1/0x4f0 fs/kernfs/file.c:325 #2: ffff888144b7e2d8 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x204/0x4f0 fs/kernfs/file.c:326 #3: ffffffff8e5419d8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:234 #4: ffff88802a01f0d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #4: ffff88802a01f0d8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1096 [inline] #4: ffff88802a01f0d8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x800 drivers/base/dd.c:1294 #5: ffff88802a01a300 (&devlink->lock_key#15){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1721 #6: ffffffff8ecd13b8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0xe5/0x670 drivers/net/netdevsim/netdev.c:1131 2 locks held by syz-executor/7109: #0: ffffffff8f1d5518 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8f1d5518 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8f1d5518 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8ecd13b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8ecd13b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8ecd13b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Tainted: G W 6.17.0-rc1-syzkaller #0 PREEMPT_{RT,(full)} Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf93/0xfe0 kernel/hung_task.c:491 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 1113 Comm: kworker/u8:6 Tainted: G W 6.17.0-rc1-syzkaller #0 PREEMPT_{RT,(full)} Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:__local_bh_enable+0x248/0x3d0 kernel/softirq.c:216 Code: 3c 30 00 74 08 48 89 df e8 a5 c0 98 00 48 c7 c7 38 ed f5 91 48 03 3b e8 d6 5f 73 09 e8 b1 47 0b 00 48 c7 44 24 20 0e 36 e0 45 <4b> c7 44 35 00 00 00 00 00 66 43 c7 44 35 09 00 00 43 c6 44 35 0b RSP: 0018:ffffc90004d8f780 EFLAGS: 00000046 RAX: b0333b0966395900 RBX: ffffffff8d24ed18 RCX: 0000000000000000 RDX: ffff8880268f8440 RSI: ffffffff8b6208e0 RDI: 00000000ffffffff RBP: ffffc90004d8f850 R08: ffff8880b8923d3b R09: 1ffff110171247a7 R10: dffffc0000000000 R11: ffffed10171247a8 R12: ffff8880268f8b0c R13: 1ffff920009b1ef4 R14: dffffc0000000000 R15: 1ffff11004d1f161 FS: 0000000000000000(0000) GS:ffff8881269c5000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffee4d18000 CR3: 0000000068aa6000 CR4: 00000000003526f0 Call Trace: __local_bh_enable_ip+0x1a4/0x270 kernel/softirq.c:262 local_bh_enable include/linux/bottom_half.h:33 [inline] spin_unlock_bh include/linux/spinlock_rt.h:111 [inline] batadv_nc_purge_paths+0x34d/0x3f0 net/batman-adv/network-coding.c:471 batadv_nc_worker+0x8c8/0xbc0 net/batman-adv/network-coding.c:722 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245