INFO: task kworker/u8:0:12 blocked for more than 143 seconds. Not tainted 6.16.0-syzkaller-12288-g2b38afce25c4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:0 state:D stack:23528 pid:12 tgid:12 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:121 __debugfs_file_removed fs/debugfs/inode.c:760 [inline] remove_one+0x312/0x420 fs/debugfs/inode.c:767 __simple_recursive_removal+0x158/0x610 fs/libfs.c:631 debugfs_remove+0x5d/0x80 fs/debugfs/inode.c:790 nsim_dev_health_exit+0x3b/0xe0 drivers/net/netdevsim/health.c:227 nsim_dev_reload_destroy+0x144/0x4d0 drivers/net/netdevsim/dev.c:1710 nsim_dev_reload_down+0x6e/0xd0 drivers/net/netdevsim/dev.c:983 devlink_reload+0x19e/0x7c0 net/devlink/dev.c:461 devlink_pernet_pre_exit+0x1a0/0x2b0 net/devlink/core.c:509 ops_pre_exit_list net/core/net_namespace.c:160 [inline] ops_undo_list+0x184/0xab0 net/core/net_namespace.c:233 cleanup_net+0x408/0x890 net/core/net_namespace.c:682 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz.1.60:6294 blocked for more than 143 seconds. Not tainted 6.16.0-syzkaller-12288-g2b38afce25c4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.60 state:D stack:29112 pid:6294 tgid:6263 ppid:5862 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x82a/0x10b0 kernel/locking/mutex.c:760 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+0x12e/0x1a0 fs/debugfs/file.c:388 vfs_write+0x29d/0x11d0 fs/read_write.c:684 ksys_write+0x12a/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x490 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa47b38ebe9 RSP: 002b:00007fa47c1d6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fa47b5b6180 RCX: 00007fa47b38ebe9 RDX: 00000000000001ff RSI: 0000000000000000 RDI: 0000000000000009 RBP: 00007fa47b411e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa47b5b6218 R14: 00007fa47b5b6180 R15: 00007ffe98699458 INFO: task syz-executor:6313 blocked for more than 144 seconds. Not tainted 6.16.0-syzkaller-12288-g2b38afce25c4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:23656 pid:6313 tgid:6313 ppid:1 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x82a/0x10b0 kernel/locking/mutex.c:760 device_lock include/linux/device.h:911 [inline] device_del+0xa0/0x9f0 drivers/base/core.c:3840 device_unregister+0x1d/0xc0 drivers/base/core.c:3919 nsim_bus_dev_del drivers/net/netdevsim/bus.c:483 [inline] del_device_store+0x355/0x4a0 drivers/net/netdevsim/bus.c:244 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:593 [inline] vfs_write+0x7d0/0x11d0 fs/read_write.c:686 ksys_write+0x12a/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x490 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f14ad18d69f RSP: 002b:00007ffe010d9e70 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f14ad18d69f RDX: 0000000000000001 RSI: 00007ffe010d9ec0 RDI: 0000000000000005 RBP: 00007f14ad2130c1 R08: 0000000000000000 R09: 00007ffe010d9cc7 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001 R13: 00007ffe010d9ec0 R14: 00007f14adee4620 R15: 0000000000000003 Showing all locks held in the system: 6 locks held by kworker/u8:0/12: #0: ffff88801c6fe948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc90000117d10 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffffffff9036f370 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xad/0x890 net/core/net_namespace.c:658 #3: ffff888050cb10e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #3: ffff888050cb10e8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff888050cb10e8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x12c/0x2b0 net/devlink/core.c:506 #4: ffff888050cb2250 (&devlink->lock_key#3){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline] #4: ffff888050cb2250 (&devlink->lock_key#3){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #4: ffff888050cb2250 (&devlink->lock_key#3){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x136/0x2b0 net/devlink/core.c:506 #5: ffff888078ba3950 (&sb->s_type->i_mutex_key#3/2){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline] #5: ffff888078ba3950 (&sb->s_type->i_mutex_key#3/2){+.+.}-{4:4}, at: __simple_recursive_removal+0x354/0x610 fs/libfs.c:627 1 lock held by khungtaskd/31: #0: ffffffff8e5c1060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c1060 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c1060 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 1 lock held by syslogd/5215: #0: ffff8880b853a458 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:636 3 locks held by syz.1.60/6294: #0: ffff888024e93eb8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2a2/0x370 fs/file.c:1232 #1: ffff88801f6c8428 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #2: ffff888050cb2250 (&devlink->lock_key#3){+.+.}-{4:4}, at: devlink_health_report+0x3ba/0x9c0 net/devlink/health.c:627 5 locks held by syz-executor/6313: #0: ffff88807d6ee428 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff888033d01488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #2: ffff8880282f31e8 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #3: ffffffff8f8f5ac8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:234 #4: ffff888050cb10e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #4: ffff888050cb10e8 (&dev->mutex){....}-{4:4}, at: device_del+0xa0/0x9f0 drivers/base/core.c:3840 4 locks held by syz-executor/6489: #0: ffff88807d6ee428 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff88805077e488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #2: ffff8880282f31e8 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #3: ffffffff8f8f5ac8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/7138: #0: ffff88807d6ee428 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff88807b15f888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #2: ffff8880282f31e8 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #3: ffffffff8f8f5ac8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/7332: #0: ffff88807d6ee428 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff88801f29d088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #2: ffff8880282f31e8 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #3: ffffffff8f8f5ac8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:234 2 locks held by getty/7906: #0: ffff88814d3480a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900030202f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 4 locks held by syz-executor/7932: #0: ffff88807d6ee428 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff88803e914c88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #2: ffff8880282f31e8 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #3: ffffffff8f8f5ac8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/8219: #0: ffff88807d6ee428 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff888083fd3488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #2: ffff8880282f31e8 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #3: ffffffff8f8f5ac8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:234 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-syzkaller-12288-g2b38afce25c4 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf0e/0x1260 kernel/hung_task.c:491 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6344 Comm: kworker/u8:10 Not tainted 6.16.0-syzkaller-12288-g2b38afce25c4 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:__trace_hardirqs_on_caller kernel/locking/lockdep.c:4351 [inline] RIP: 0010:lockdep_hardirqs_on_prepare+0xea/0x1d0 kernel/locking/lockdep.c:4410 Code: 00 00 85 c0 75 24 48 c7 c7 4d 65 e2 8d e8 ee 08 f9 09 b8 ff ff ff ff 65 0f c1 05 09 a6 3e 12 83 f8 01 75 15 5b e9 d6 f8 fb 09 06 00 00 00 48 89 df e8 79 fe ff ff eb cd 90 0f 0b 90 48 c7 c7 RSP: 0018:ffffc90004b37a80 EFLAGS: 00000002 RAX: 0000000000000001 RBX: ffff888030089e00 RCX: 0000000000000002 RDX: 0000000000000000 RSI: ffff88803008a918 RDI: ffff888030089e00 RBP: ffffffff8b5d20c4 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff90ab6b97 R11: 0000000000000000 R12: ffffffff8b5d2470 R13: ffff888043b68000 R14: ffff8880226a0d80 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881246c6000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe594cfe08 CR3: 000000000e380000 CR4: 00000000003526f0 Call Trace: trace_hardirqs_on+0x36/0x40 kernel/trace/trace_preemptirq.c:78 __local_bh_enable_ip+0xa4/0x120 kernel/softirq.c:412 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_nc_purge_paths+0x1d4/0x3a0 net/batman-adv/network-coding.c:471 batadv_nc_worker+0x921/0x1030 net/batman-adv/network-coding.c:720 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245