INFO: task syz-executor:29260 blocked for more than 143 seconds. Tainted: G U 6.15.0-rc5-syzkaller-00043-gd76bb1ebb558 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:24920 pid:29260 tgid:29260 ppid:1 task_flags:0x480140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:116 __debugfs_file_removed fs/debugfs/inode.c:775 [inline] remove_one+0x312/0x420 fs/debugfs/inode.c:782 simple_recursive_removal+0x4e2/0x8e0 fs/libfs.c:635 debugfs_remove+0x5d/0x80 fs/debugfs/inode.c:805 nsim_dev_health_exit+0x3b/0xe0 drivers/net/netdevsim/health.c:227 nsim_dev_reload_destroy+0x144/0x4d0 drivers/net/netdevsim/dev.c:1664 nsim_drv_remove+0x52/0x1d0 drivers/net/netdevsim/dev.c:1676 device_remove+0xc8/0x170 drivers/base/dd.c:567 __device_release_driver drivers/base/dd.c:1272 [inline] device_release_driver_internal+0x44b/0x620 drivers/base/dd.c:1295 bus_remove_device+0x22f/0x420 drivers/base/bus.c:579 device_del+0x396/0x9f0 drivers/base/core.c:3881 device_unregister+0x1d/0xc0 drivers/base/core.c:3922 nsim_bus_dev_del drivers/net/netdevsim/bus.c:462 [inline] del_device_store+0x355/0x4a0 drivers/net/netdevsim/bus.c:226 bus_attr_store+0x71/0xb0 drivers/base/bus.c:172 sysfs_kf_write+0xef/0x150 fs/sysfs/file.c:145 kernfs_fop_write_iter+0x351/0x510 fs/kernfs/file.c:334 new_sync_write fs/read_write.c:591 [inline] vfs_write+0x5ba/0x1180 fs/read_write.c:684 ksys_write+0x12a/0x240 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc9d078d41f RSP: 002b:00007ffed50567b0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fc9d078d41f RDX: 0000000000000001 RSI: 00007ffed5056800 RDI: 0000000000000005 RBP: 00007fc9d0811d05 R08: 0000000000000000 R09: 00007ffed5056607 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001 R13: 00007ffed5056800 R14: 00007fc9d14e4620 R15: 0000000000000003 INFO: task syz.6.4671:29371 blocked for more than 143 seconds. Tainted: G U 6.15.0-rc5-syzkaller-00043-gd76bb1ebb558 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.4671 state:D stack:26984 pid:29371 tgid:29370 ppid:28122 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x6c7/0xb90 kernel/locking/mutex.c:746 devlink_health_report+0x3ba/0x9c0 net/devlink/health.c:627 nsim_dev_health_break_write+0x166/0x210 drivers/net/netdevsim/health.c:162 full_proxy_write+0x13c/0x200 fs/debugfs/file.c:398 vfs_write+0x25c/0x1180 fs/read_write.c:682 ksys_write+0x12a/0x240 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f424338e969 RSP: 002b:00007f42441f2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f42435b5fa0 RCX: 00007f424338e969 RDX: 00000000000001ff RSI: 0000000000000000 RDI: 0000000000000006 RBP: 00007f4243410ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f42435b5fa0 R15: 00007fff58f2b2d8 Showing all locks held in the system: 1 lock held by ksoftirqd/1/23: 1 lock held by khungtaskd/31: #0: ffffffff8e3bf440 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e3bf440 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e3bf440 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764 2 locks held by getty/18724: #0: ffff8880316840a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000bef32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 6 locks held by syz-executor/19101: 6 locks held by kworker/u8:6/19651: #0: ffff88801c2f6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000adffd18 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffffffff90110710 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xc9/0xb30 net/core/net_namespace.c:608 #3: ffffffff901265a8 (rtnl_mutex){+.+.}-{4:4}, at: wg_netns_pre_exit+0x1b/0x230 drivers/net/wireguard/device.c:416 #4: ffff888029fa14e8 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_netns_pre_exit+0xdd/0x230 drivers/net/wireguard/device.c:421 #5: ffffffff8e3ca978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x280/0x3c0 kernel/rcu/tree_exp.h:304 3 locks held by kworker/u8:33/19865: #0: ffff88801b489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000ba97d18 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffffffff901265a8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:303 7 locks held by syz-executor/29260: #0: ffff888031d44420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x240 fs/read_write.c:736 #1: ffff88804bffac88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #2: ffff888027f80788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #3: ffffffff8f6c8b88 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:216 #4: ffff8880254af0e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #4: ffff8880254af0e8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1094 [inline] #4: ffff8880254af0e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xa4/0x620 drivers/base/dd.c:1292 #5: ffff888065569250 (&devlink->lock_key#8){+.+.}-{4:4}, at: nsim_drv_remove+0x4a/0x1d0 drivers/net/netdevsim/dev.c:1675 #6: ffff88804caf5ac0 (&sb->s_type->i_mutex_key#3){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #6: ffff88804caf5ac0 (&sb->s_type->i_mutex_key#3){++++}-{4:4}, at: simple_recursive_removal+0x2f5/0x8e0 fs/libfs.c:627 3 locks held by syz.6.4671/29371: #0: ffff888012b30d38 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2a2/0x370 fs/file.c:1213 #1: ffff88801f2e8420 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12a/0x240 fs/read_write.c:736 #2: ffff888065569250 (&devlink->lock_key#8){+.+.}-{4:4}, at: devlink_health_report+0x3ba/0x9c0 net/devlink/health.c:627 4 locks held by syz-executor/29635: #0: ffff888031d44420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x240 fs/read_write.c:736 #1: ffff88808ce0c088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #2: ffff888027f80788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #3: ffffffff8f6c8b88 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/30094: #0: ffff888031d44420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x240 fs/read_write.c:736 #1: ffff8880637d6488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #2: ffff888027f80788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #3: ffffffff8f6c8b88 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:216 5 locks held by syz.7.4835/30263: #0: ffff88807d43f438 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2a2/0x370 fs/file.c:1213 #1: ffff888031d44420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x240 fs/read_write.c:736 #2: ffff88807b866888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #3: ffff888027f80788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #4: ffffffff8f6c8b88 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/30377: #0: ffff888031d44420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x240 fs/read_write.c:736 #1: ffff88805aca5888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #2: ffff888027f80788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #3: ffffffff8f6c8b88 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/30398: #0: ffff888031d44420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x240 fs/read_write.c:736 #1: ffff8880259b4488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #2: ffff888027f80788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #3: ffffffff8f6c8b88 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/30426: #0: ffff888031d44420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x240 fs/read_write.c:736 #1: ffff8880341fac88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #2: ffff888027f80788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #3: ffffffff8f6c8b88 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/30442: #0: ffff888031d44420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x240 fs/read_write.c:736 #1: ffff888063bff888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #2: ffff888027f80788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #3: ffffffff8f6c8b88 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/30453: #0: ffff888031d44420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x240 fs/read_write.c:736 #1: ffff888034147c88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #2: ffff888027f80788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #3: ffffffff8f6c8b88 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:216 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G U 6.15.0-rc5-syzkaller-00043-gd76bb1ebb558 #0 PREEMPT(full) Tainted: [U]=USER Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:437 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 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: 19646 Comm: kworker/u8:1 Tainted: G U 6.15.0-rc5-syzkaller-00043-gd76bb1ebb558 #0 PREEMPT(full) Tainted: [U]=USER Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:check_preemption_disabled+0x3/0xe0 lib/smp_processor_id.c:13 Code: 65 8b 05 fc 1e 3a 08 85 c0 74 04 90 0f 0b 90 e9 53 fc ff ff 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 54 55 <53> 48 83 ec 08 65 8b 1d b5 e4 39 08 65 8b 05 aa e4 39 08 a9 ff ff RSP: 0018:ffffc9000ad9fb00 EFLAGS: 00000283 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff8b36cbf7 RDX: ffff888030658000 RSI: ffffffff8bf46be0 RDI: ffffffff8bf46c20 RBP: 00000000000002cc R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888124aec000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000562cdd7e3168 CR3: 000000000e180000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] rcu_is_watching+0x12/0xc0 kernel/rcu/tree.c:736 rcu_read_unlock include/linux/rcupdate.h:869 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline] batadv_nc_worker+0xb8d/0x1030 net/batman-adv/network-coding.c:719 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245