INFO: task syz-executor:15424 blocked for more than 143 seconds. Tainted: G U 6.14.0-rc7-syzkaller-00137-g5fc319360819 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:23280 pid:15424 tgid:15424 ppid:1 task_flags:0x480140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 schedule_timeout+0x244/0x280 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x3e1/0x600 kernel/sched/completion.c:116 __debugfs_file_removed fs/debugfs/inode.c:775 [inline] remove_one+0x30f/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+0x143/0x4d0 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:1273 [inline] device_release_driver_internal+0x44a/0x610 drivers/base/dd.c:1296 bus_remove_device+0x22f/0x420 drivers/base/bus.c:579 device_del+0x396/0x9f0 drivers/base/core.c:3855 device_unregister+0x1d/0xc0 drivers/base/core.c:3896 nsim_bus_dev_del drivers/net/netdevsim/bus.c:462 [inline] del_device_store+0x346/0x4b0 drivers/net/netdevsim/bus.c:226 bus_attr_store+0x71/0xb0 drivers/base/bus.c:172 sysfs_kf_write+0x117/0x170 fs/sysfs/file.c:139 kernfs_fop_write_iter+0x33d/0x500 fs/kernfs/file.c:334 new_sync_write fs/read_write.c:586 [inline] vfs_write+0x5ae/0x1150 fs/read_write.c:679 ksys_write+0x12b/0x250 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3c58f8bc1f RSP: 002b:00007ffce48a7e10 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f3c58f8bc1f RDX: 0000000000000001 RSI: 00007ffce48a7e60 RDI: 0000000000000005 RBP: 00007f3c5900f4fd R08: 0000000000000000 R09: 00007ffce48a7c67 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001 R13: 00007ffce48a7e60 R14: 00007f3c59cd4620 R15: 0000000000000003 INFO: task syz.5.2359:15604 blocked for more than 144 seconds. Tainted: G U 6.14.0-rc7-syzkaller-00137-g5fc319360819 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.2359 state:D stack:27904 pid:15604 tgid:15603 ppid:12850 task_flags:0x400140 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x6bd/0xb10 kernel/locking/mutex.c:730 devlink_health_report+0x3c5/0x9d0 net/devlink/health.c:627 nsim_dev_health_break_write+0x167/0x210 drivers/net/netdevsim/health.c:162 full_proxy_write+0x13c/0x200 fs/debugfs/file.c:398 vfs_write+0x24c/0x1150 fs/read_write.c:677 ksys_write+0x12b/0x250 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f085df8d169 RSP: 002b:00007f085bdf6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f085e1a5fa0 RCX: 00007f085df8d169 RDX: 00000000000000ef RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00007f085e00e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f085e1a5fa0 R15: 00007ffe23fb1368 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746 2 locks held by getty/5597: #0: ffff8880318fd0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900033032f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 1 lock held by syz.2.438/7614: 3 locks held by kworker/u8:16/14197: 7 locks held by syz-executor/15424: #0: ffff88803104c420 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12b/0x250 fs/read_write.c:731 #1: ffff888025b6cc88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x27b/0x500 fs/kernfs/file.c:325 #2: ffff888027a0ee18 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x29e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f4a4bc8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd2/0x4b0 drivers/net/netdevsim/bus.c:216 #4: ffff888062cf40e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #4: ffff888062cf40e8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff888062cf40e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xa4/0x610 drivers/base/dd.c:1293 #5: ffff888062cf5250 (&devlink->lock_key#2){+.+.}-{4:4}, at: nsim_drv_remove+0x4a/0x1d0 drivers/net/netdevsim/dev.c:1675 #6: ffff88807af16f20 (&sb->s_type->i_mutex_key#3){++++}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline] #6: ffff88807af16f20 (&sb->s_type->i_mutex_key#3){++++}-{4:4}, at: simple_recursive_removal+0x2f5/0x8e0 fs/libfs.c:627 3 locks held by syz.5.2359/15604: #0: ffff88804700a638 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x267/0x390 fs/file.c:1192 #1: ffff888141ae2420 (sb_writers#9){.+.+}-{0:0}, at: ksys_write+0x12b/0x250 fs/read_write.c:731 #2: ffff888062cf5250 (&devlink->lock_key#2){+.+.}-{4:4}, at: devlink_health_report+0x3c5/0x9d0 net/devlink/health.c:627 4 locks held by syz-executor/15765: #0: ffff88803104c420 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12b/0x250 fs/read_write.c:731 #1: ffff888036af5888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x27b/0x500 fs/kernfs/file.c:325 #2: ffff888027a0ee18 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x29e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f4a4bc8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd2/0x4b0 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/15885: #0: ffff88803104c420 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12b/0x250 fs/read_write.c:731 #1: ffff888046477488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x27b/0x500 fs/kernfs/file.c:325 #2: ffff888027a0ee18 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x29e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f4a4bc8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd2/0x4b0 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/16217: #0: ffff88803104c420 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12b/0x250 fs/read_write.c:731 #1: ffff888022ed2088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x27b/0x500 fs/kernfs/file.c:325 #2: ffff888027a0ee18 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x29e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f4a4bc8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd2/0x4b0 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/16417: #0: ffff88803104c420 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12b/0x250 fs/read_write.c:731 #1: ffff88802f04dc88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x27b/0x500 fs/kernfs/file.c:325 #2: ffff888027a0ee18 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x29e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f4a4bc8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd2/0x4b0 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/16442: #0: ffff88803104c420 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12b/0x250 fs/read_write.c:731 #1: ffff888032ac6488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x27b/0x500 fs/kernfs/file.c:325 #2: ffff888027a0ee18 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x29e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f4a4bc8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd2/0x4b0 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/16586: #0: ffff88803104c420 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12b/0x250 fs/read_write.c:731 #1: ffff888026602888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x27b/0x500 fs/kernfs/file.c:325 #2: ffff888027a0ee18 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x29e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f4a4bc8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd2/0x4b0 drivers/net/netdevsim/bus.c:216 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G U 6.14.0-rc7-syzkaller-00137-g5fc319360819 #0 Tainted: [U]=USER Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 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:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline] watchdog+0xf62/0x12b0 kernel/hung_task.c:399 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244