INFO: task kworker/u8:0:12 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:0 state:D stack:25128 pid:12 tgid:12 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0xfe4/0x5e10 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0xdd/0x390 kernel/sched/core.c:6964 schedule_timeout+0x1b2/0x280 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common+0x2e7/0x4c0 kernel/sched/completion.c:121 __debugfs_file_removed fs/debugfs/inode.c:751 [inline] remove_one+0x312/0x420 fs/debugfs/inode.c:758 __simple_recursive_removal+0x148/0x5c0 fs/libfs.c:623 debugfs_remove+0x5d/0x80 fs/debugfs/inode.c:781 nsim_dev_health_exit+0x3b/0xe0 drivers/net/netdevsim/health.c:227 nsim_dev_reload_destroy+0x144/0x4a0 drivers/net/netdevsim/dev.c:1767 nsim_dev_reload_down+0x66/0xd0 drivers/net/netdevsim/dev.c:1038 devlink_reload+0x173/0x7b0 net/devlink/dev.c:461 devlink_pernet_pre_exit+0x222/0x330 net/devlink/core.c:509 ops_pre_exit_list net/core/net_namespace.c:161 [inline] ops_undo_list+0x187/0xab0 net/core/net_namespace.c:234 cleanup_net+0x419/0x830 net/core/net_namespace.c:696 process_one_work+0x9c2/0x1840 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3421 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 INFO: task syz-executor:12417 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:23928 pid:12417 tgid:12417 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0xfe4/0x5e10 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0xdd/0x390 kernel/sched/core.c:6964 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776 device_lock include/linux/device.h:895 [inline] device_del+0xa0/0x9b0 drivers/base/core.c:3840 device_unregister+0x1d/0xe0 drivers/base/core.c:3919 nsim_bus_dev_del drivers/net/netdevsim/bus.c:491 [inline] del_device_store+0x346/0x480 drivers/net/netdevsim/bus.c:244 bus_attr_store+0x74/0xb0 drivers/base/bus.c:172 sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:142 kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x6ac/0x1070 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+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd36cf5b80e RSP: 002b:00007ffd7b48bab8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000555571ab5500 RCX: 00007fd36cf5b80e RDX: 0000000000000001 RSI: 00007ffd7b48bb40 RDI: 0000000000000005 RBP: 00007fd36d0307d3 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffd7b48bb40 R14: 00007fd36dd34620 R15: 0000000000000003 INFO: task syz.0.2859:12465 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.2859 state:D stack:28744 pid:12465 tgid:12462 ppid:11382 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0xfe4/0x5e10 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0xdd/0x390 kernel/sched/core.c:6964 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776 devlink_health_report+0x62b/0xa80 net/devlink/health.c:680 nsim_dev_health_break_write+0x166/0x210 drivers/net/netdevsim/health.c:162 full_proxy_write+0x135/0x1a0 fs/debugfs/file.c:388 vfs_write+0x2aa/0x1070 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+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8d2619af39 RSP: 002b:00007f8d27012028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f8d26405fa0 RCX: 00007f8d2619af39 RDX: 00000000000001e1 RSI: 0000200000000080 RDI: 0000000000000003 RBP: 00007f8d2622fee0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8d26406038 R14: 00007f8d26405fa0 R15: 00007ffe7dd9e0b8 INFO: task syz.3.2880:12508 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.2880 state:D stack:29032 pid:12508 tgid:12507 ppid:6353 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0xfe4/0x5e10 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0xdd/0x390 kernel/sched/core.c:6964 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021 rwsem_down_read_slowpath+0x5dc/0xb30 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1261 [inline] __down_read kernel/locking/rwsem.c:1274 [inline] down_read+0xed/0x460 kernel/locking/rwsem.c:1539 inode_lock_shared include/linux/fs.h:1042 [inline] open_last_lookups fs/namei.c:4548 [inline] path_openat+0xa19/0x3120 fs/namei.c:4793 do_filp_open+0x1f7/0x420 fs/namei.c:4823 do_sys_openat2+0x12e/0x220 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x12d/0x210 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f58e159af39 RSP: 002b:00007f58e23b7028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f58e1805fa0 RCX: 00007f58e159af39 RDX: 0000000000048081 RSI: 0000200000000000 RDI: ffffffffffffff9c RBP: 00007f58e162fee0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f58e1806038 R14: 00007f58e1805fa0 R15: 00007ffc2ef15e98 INFO: task syz.1.2879:12510 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.2879 state:D stack:29032 pid:12510 tgid:12509 ppid:6346 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0xfe4/0x5e10 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0xdd/0x390 kernel/sched/core.c:6964 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021 rwsem_down_read_slowpath+0x5dc/0xb30 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1261 [inline] __down_read kernel/locking/rwsem.c:1274 [inline] down_read+0xed/0x460 kernel/locking/rwsem.c:1539 inode_lock_shared include/linux/fs.h:1042 [inline] open_last_lookups fs/namei.c:4548 [inline] path_openat+0xa19/0x3120 fs/namei.c:4793 do_filp_open+0x1f7/0x420 fs/namei.c:4823 do_sys_openat2+0x12e/0x220 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x12d/0x210 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe3a219af39 RSP: 002b:00007fe3a2fc1028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fe3a2405fa0 RCX: 00007fe3a219af39 RDX: 0000000000048081 RSI: 0000200000000000 RDI: ffffffffffffff9c RBP: 00007fe3a222fee0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe3a2406038 R14: 00007fe3a2405fa0 R15: 00007ffe6fc45db8 Showing all locks held in the system: 6 locks held by kworker/u8:0/12: #0: ffff88801c29f148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc90000117c98 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 #2: ffffffff903dd0b0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xab/0x830 net/core/net_namespace.c:670 #3: ffff8880635bc0e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #3: ffff8880635bc0e8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff8880635bc0e8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x185/0x330 net/devlink/core.c:506 #4: ffff888029d75250 (&devlink->lock_key#6){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline] #4: ffff888029d75250 (&devlink->lock_key#6){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #4: ffff888029d75250 (&devlink->lock_key#6){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x18f/0x330 net/devlink/core.c:506 #5: ffff888041fdcb58 (&sb->s_type->i_mutex_key#9/2){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1072 [inline] #5: ffff888041fdcb58 (&sb->s_type->i_mutex_key#9/2){+.+.}-{4:4}, at: __simple_recursive_removal+0xe0/0x5c0 fs/libfs.c:619 1 lock held by khungtaskd/31: #0: ffffffff8e5e3120 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5e3120 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e5e3120 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 2 locks held by getty/5583: #0: ffff88814e00d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211 5 locks held by syz-executor/12417: #0: ffff888034082420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff888059be2488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343 #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x332/0x5f0 fs/kernfs/file.c:344 #3: ffffffff8f950008 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x480 drivers/net/netdevsim/bus.c:234 #4: ffff8880635bc0e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #4: ffff8880635bc0e8 (&dev->mutex){....}-{4:4}, at: device_del+0xa0/0x9b0 drivers/base/core.c:3840 3 locks held by syz.0.2859/12465: #0: ffff88807a311b38 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1255 #1: ffff888142288420 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #2: ffff888029d75250 (&devlink->lock_key#6){+.+.}-{4:4}, at: devlink_health_report+0x62b/0xa80 net/devlink/health.c:680 2 locks held by syz.3.2880/12508: #0: ffff888142288420 (sb_writers#8){.+.+}-{0:0}, at: open_last_lookups fs/namei.c:4538 [inline] #0: ffff888142288420 (sb_writers#8){.+.+}-{0:0}, at: path_openat+0x9b3/0x3120 fs/namei.c:4793 #1: ffff888041fdcb58 (&sb->s_type->i_mutex_key#17){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1042 [inline] #1: ffff888041fdcb58 (&sb->s_type->i_mutex_key#17){++++}-{4:4}, at: open_last_lookups fs/namei.c:4548 [inline] #1: ffff888041fdcb58 (&sb->s_type->i_mutex_key#17){++++}-{4:4}, at: path_openat+0xa19/0x3120 fs/namei.c:4793 2 locks held by syz.1.2879/12510: #0: ffff888142288420 (sb_writers#8){.+.+}-{0:0}, at: open_last_lookups fs/namei.c:4538 [inline] #0: ffff888142288420 (sb_writers#8){.+.+}-{0:0}, at: path_openat+0x9b3/0x3120 fs/namei.c:4793 #1: ffff888041fdcb58 (&sb->s_type->i_mutex_key#17){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1042 [inline] #1: ffff888041fdcb58 (&sb->s_type->i_mutex_key#17){++++}-{4:4}, at: open_last_lookups fs/namei.c:4548 [inline] #1: ffff888041fdcb58 (&sb->s_type->i_mutex_key#17){++++}-{4:4}, at: path_openat+0xa19/0x3120 fs/namei.c:4793 4 locks held by syz-executor/12518: #0: ffff888034082420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff888061d18888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343 #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x332/0x5f0 fs/kernfs/file.c:344 #3: ffffffff8f950008 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x480 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/12529: #0: ffff888034082420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff888078d4b088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343 #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x332/0x5f0 fs/kernfs/file.c:344 #3: ffffffff8f950008 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x480 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/12531: #0: ffff888034082420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff888067fa5488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343 #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x332/0x5f0 fs/kernfs/file.c:344 #3: ffffffff8f950008 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x480 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/12555: #0: ffff888034082420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff888143739488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343 #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x332/0x5f0 fs/kernfs/file.c:344 #3: ffffffff8f950008 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x480 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/12566: #0: ffff888034082420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff88805c840488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343 #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x332/0x5f0 fs/kernfs/file.c:344 #3: ffffffff8f950008 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x480 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/12577: #0: ffff888034082420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff8880564c5488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343 #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x332/0x5f0 fs/kernfs/file.c:344 #3: ffffffff8f950008 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x480 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/12579: #0: ffff888034082420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff888042512488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343 #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x332/0x5f0 fs/kernfs/file.c:344 #3: ffffffff8f950008 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x480 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/12603: #0: ffff888034082420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff88807d48cc88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343 #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x332/0x5f0 fs/kernfs/file.c:344 #3: ffffffff8f950008 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x480 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/12613: #0: ffff888034082420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff888078d5d488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343 #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x332/0x5f0 fs/kernfs/file.c:344 #3: ffffffff8f950008 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x480 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/12625: #0: ffff888034082420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff88807d75b488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343 #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x332/0x5f0 fs/kernfs/file.c:344 #3: ffffffff8f950008 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x480 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/12626: #0: ffff888034082420 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff888076a02088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343 #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8881427480f8 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x332/0x5f0 fs/kernfs/file.c:344 #3: ffffffff8f950008 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x480 drivers/net/netdevsim/bus.c:234 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xcc3/0xfe0 kernel/hung_task.c:515 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 198 Comm: kworker/u8:5 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:__lock_is_held kernel/locking/lockdep.c:5601 [inline] RIP: 0010:lock_is_held_type+0x92/0x140 kernel/locking/lockdep.c:5940 Code: 85 28 0b 00 00 85 c0 0f 8e 94 00 00 00 4c 8d b5 30 0b 00 00 45 31 ff eb 11 41 83 c7 01 49 83 c6 28 44 3b bd 28 0b 00 00 7d 77 <48> 89 de 4c 89 f7 e8 a3 fe ff ff 85 c0 74 e0 41 83 fc ff 74 13 31 RSP: 0018:ffffc90002e577c8 EFLAGS: 00000097 RAX: 0000000000000000 RBX: ffffffff8e5e3060 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff8e5e3060 RDI: ffff88801fb266d8 RBP: ffff88801fb25b80 R08: 0000000000000000 R09: fffffbfff216ee3a R10: ffffffff90b771d7 R11: 0000005225795800 R12: 00000000ffffffff R13: 0000000000000046 R14: ffff88801fb26700 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff8881246e3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005559960e6a38 CR3: 000000000e392000 CR4: 00000000003526f0 Call Trace: lock_is_held include/linux/lockdep.h:249 [inline] rcu_read_lock_sched_held kernel/rcu/update.c:126 [inline] rcu_read_lock_sched_held+0x40/0x70 kernel/rcu/update.c:120 task_css_set include/linux/cgroup.h:447 [inline] task_dfl_cgroup include/linux/cgroup.h:516 [inline] cgroup_account_cputime include/linux/cgroup.h:744 [inline] update_se+0x526/0x700 kernel/sched/fair.c:1163 update_curr+0x71/0x560 kernel/sched/fair.c:1209 dequeue_entity kernel/sched/fair.c:5353 [inline] dequeue_entities+0x162/0x2e70 kernel/sched/fair.c:7026 dequeue_task_fair+0x1aa/0x9b0 kernel/sched/fair.c:7125 block_task kernel/sched/core.c:2158 [inline] try_to_block_task kernel/sched/core.c:6491 [inline] __schedule+0x34d6/0x5e10 kernel/sched/core.c:6803 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0xdd/0x390 kernel/sched/core.c:6964 toggle_allocation_gate mm/kfence/core.c:881 [inline] toggle_allocation_gate+0x218/0x2d0 mm/kfence/core.c:871 process_one_work+0x9c2/0x1840 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3421 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246