INFO: task syz-executor:14418 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:22472 pid:14418 tgid:14418 ppid:1 task_flags:0x480140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17e7/0x5600 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2a0 kernel/sched/core.c:7326 schedule_timeout+0xc0/0x2c0 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x2ca/0x5e0 kernel/sched/completion.c:153 __debugfs_file_removed fs/debugfs/inode.c:751 [inline] remove_one+0x2df/0x3b0 fs/debugfs/inode.c:758 __simple_recursive_removal+0x215/0x520 fs/libfs.c:623 debugfs_remove+0x5b/0x70 fs/debugfs/inode.c:781 nsim_dev_debugfs_exit drivers/net/netdevsim/dev.c:372 [inline] nsim_drv_remove+0xc0/0x170 drivers/net/netdevsim/dev.c:1803 device_remove drivers/base/dd.c:616 [inline] __device_release_driver drivers/base/dd.c:1349 [inline] device_release_driver_internal+0x48b/0x880 drivers/base/dd.c:1372 bus_remove_device+0x444/0x560 drivers/base/bus.c:664 device_del+0x524/0x8f0 drivers/base/core.c:3961 device_unregister+0x21/0xf0 drivers/base/core.c:4002 nsim_bus_dev_del drivers/net/netdevsim/bus.c:491 [inline] del_device_store+0x2b5/0x370 drivers/net/netdevsim/bus.c:244 kernfs_fop_write_iter+0x3b1/0x540 fs/kernfs/file.c:345 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x612/0xba0 fs/read_write.c:687 ksys_write+0x150/0x270 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10a/0x4d0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fa75135e84e RSP: 002b:00007ffca1ebdc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000055556c37b500 RCX: 00007fa75135e84e RDX: 0000000000000001 RSI: 00007ffca1ebdcf0 RDI: 0000000000000005 RBP: 00007fa75143588f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffca1ebdcf0 R14: 00007fa752154620 R15: 0000000000000003 INFO: task syz.2.3944:14968 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.3944 state:D stack:27448 pid:14968 tgid:14966 ppid:12324 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17e7/0x5600 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2a0 kernel/sched/core.c:7326 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x6cf/0x15e0 kernel/locking/mutex.c:821 nsim_bus_dev_max_vfs_write+0x236/0x3d0 drivers/net/netdevsim/dev.c:276 full_proxy_write+0x127/0x1f0 fs/debugfs/file.c:388 vfs_write+0x296/0xba0 fs/read_write.c:685 ksys_write+0x150/0x270 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10a/0x4d0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f0258d9e019 RSP: 002b:00007f0259d52028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f0259025fa0 RCX: 00007f0258d9e019 RDX: 0000000000000001 RSI: 0000200000000180 RDI: 0000000000000003 RBP: 00007f0258e3500c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0259026038 R14: 00007f0259025fa0 R15: 00007ffcc3f85d88 INFO: task syz.2.3944:14968 is blocked on a mutex likely owned by task syz-executor:14418. INFO: task syz.3.3946:14969 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.3946 state:D stack:27824 pid:14969 tgid:14967 ppid:13341 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17e7/0x5600 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2a0 kernel/sched/core.c:7326 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x6cf/0x15e0 kernel/locking/mutex.c:821 nsim_bus_dev_max_vfs_write+0x236/0x3d0 drivers/net/netdevsim/dev.c:276 full_proxy_write+0x127/0x1f0 fs/debugfs/file.c:388 vfs_write+0x296/0xba0 fs/read_write.c:685 ksys_write+0x150/0x270 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10a/0x4d0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fe95eb9e019 RSP: 002b:00007fe95fae0028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fe95ee25fa0 RCX: 00007fe95eb9e019 RDX: 0000000000000001 RSI: 0000200000000180 RDI: 0000000000000003 RBP: 00007fe95ec3500c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe95ee26038 R14: 00007fe95ee25fa0 R15: 00007ffc78319278 INFO: task syz.3.3946:14969 is blocked on a mutex likely owned by task syz-executor:14418. INFO: task syz.1.3945:14972 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.3945 state:D stack:28400 pid:14972 tgid:14970 ppid:11293 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17e7/0x5600 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2a0 kernel/sched/core.c:7326 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x6cf/0x15e0 kernel/locking/mutex.c:821 nsim_bus_dev_max_vfs_write+0x236/0x3d0 drivers/net/netdevsim/dev.c:276 full_proxy_write+0x127/0x1f0 fs/debugfs/file.c:388 vfs_write+0x296/0xba0 fs/read_write.c:685 ksys_write+0x150/0x270 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10a/0x4d0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fa17ad9e019 RSP: 002b:00007fa17bcce028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fa17b025fa0 RCX: 00007fa17ad9e019 RDX: 0000000000000001 RSI: 0000200000000180 RDI: 0000000000000003 RBP: 00007fa17ae3500c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa17b026038 R14: 00007fa17b025fa0 R15: 00007ffc97063b28 INFO: task syz.1.3945:14972 is blocked on a mutex likely owned by task syz-executor:14418. Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e542100 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e542100 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffffffff8e542100 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5373: #0: ffff8880350690a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211 7 locks held by syz-executor/14418: #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683 #1: ffff888079f6f880 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e5/0x540 fs/kernfs/file.c:336 #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline] #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x238/0x540 fs/kernfs/file.c:337 #3: ffffffff8f210660 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234 #4: ffff888028d0d128 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline] #4: ffff888028d0d128 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1171 [inline] #4: ffff888028d0d128 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb9/0x880 drivers/base/dd.c:1369 #5: ffff888028d0c258 (&devlink->lock_key#5){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x170 drivers/net/netdevsim/dev.c:1799 #6: ffff888057549480 (&sb->s_type->i_mutex_key#9/2){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline] #6: ffff888057549480 (&sb->s_type->i_mutex_key#9/2){+.+.}-{4:4}, at: __simple_recursive_removal+0x19a/0x520 fs/libfs.c:619 3 locks held by syz.2.3944/14968: #0: ffff888033113430 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1259 #1: ffff88801e6b6450 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #1: ffff88801e6b6450 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683 #2: ffff888028d0c258 (&devlink->lock_key#5){+.+.}-{4:4}, at: nsim_bus_dev_max_vfs_write+0x236/0x3d0 drivers/net/netdevsim/dev.c:276 3 locks held by syz.3.3946/14969: #0: ffff888030ea4630 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1259 #1: ffff88801e6b6450 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #1: ffff88801e6b6450 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683 #2: ffff888028d0c258 (&devlink->lock_key#5){+.+.}-{4:4}, at: nsim_bus_dev_max_vfs_write+0x236/0x3d0 drivers/net/netdevsim/dev.c:276 3 locks held by syz.1.3945/14972: #0: ffff888030ea4b70 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1259 #1: ffff88801e6b6450 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #1: ffff88801e6b6450 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683 #2: ffff888028d0c258 (&devlink->lock_key#5){+.+.}-{4:4}, at: nsim_bus_dev_max_vfs_write+0x236/0x3d0 drivers/net/netdevsim/dev.c:276 4 locks held by syz-executor/15037: #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683 #1: ffff88807a661480 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e5/0x540 fs/kernfs/file.c:336 #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline] #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x238/0x540 fs/kernfs/file.c:337 #3: ffffffff8f210660 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/15038: #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683 #1: ffff888079649080 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e5/0x540 fs/kernfs/file.c:336 #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline] #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x238/0x540 fs/kernfs/file.c:337 #3: ffffffff8f210660 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/15043: #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683 #1: ffff88806f53d480 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e5/0x540 fs/kernfs/file.c:336 #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline] #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x238/0x540 fs/kernfs/file.c:337 #3: ffffffff8f210660 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/15098: #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683 #1: ffff88807e6acc80 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e5/0x540 fs/kernfs/file.c:336 #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline] #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x238/0x540 fs/kernfs/file.c:337 #3: ffffffff8f210660 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/15119: #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683 #1: ffff888055ced080 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e5/0x540 fs/kernfs/file.c:336 #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline] #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x238/0x540 fs/kernfs/file.c:337 #3: ffffffff8f210660 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/15122: #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683 #1: ffff8880254fc080 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e5/0x540 fs/kernfs/file.c:336 #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline] #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x238/0x540 fs/kernfs/file.c:337 #3: ffffffff8f210660 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/15123: #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683 #1: ffff8880254fdc80 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e5/0x540 fs/kernfs/file.c:336 #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline] #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x238/0x540 fs/kernfs/file.c:337 #3: ffffffff8f210660 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/15183: #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683 #1: ffff888071cb2080 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e5/0x540 fs/kernfs/file.c:336 #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline] #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x238/0x540 fs/kernfs/file.c:337 #3: ffffffff8f210660 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/15205: #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683 #1: ffff88802ecedc80 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e5/0x540 fs/kernfs/file.c:336 #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline] #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x238/0x540 fs/kernfs/file.c:337 #3: ffffffff8f210660 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/15208: #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683 #1: ffff88802ecefc80 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e5/0x540 fs/kernfs/file.c:336 #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline] #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x238/0x540 fs/kernfs/file.c:337 #3: ffffffff8f210660 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234 4 locks held by syz-executor/15209: #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #0: ffff8880354d0450 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683 #1: ffff888059849880 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e5/0x540 fs/kernfs/file.c:336 #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline] #2: ffff888028a77c38 (kn->active#56){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x238/0x540 fs/kernfs/file.c:337 #3: ffffffff8f210660 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234 2 locks held by dhcpcd/15258: #0: ffff888034c14258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline] #0: ffff888034c14258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xd50 net/packet/af_packet.c:3204 #1: ffffffff8e547768 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #1: ffffffff8e547768 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122 nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0x16d0/0x1730 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x510/0xb60 arch/x86/kernel/process.c:158 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: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64 Code: 00 63 02 c3 cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 93 6b 12 00 fb f4 cc fe 02 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 RSP: 0018:ffffffff8e207de0 EFLAGS: 00000242 RAX: 00000000001977ef RBX: ffffffff8199a9b0 RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8dcd4c7d RDI: ffffffff8c055980 RBP: ffffffff8e207eb8 R08: ffff8880b863391b R09: 1ffff110170c6723 R10: dffffc0000000000 R11: ffffed10170c6724 R12: 0000000000000000 R13: 1ffffffff1c51dd8 R14: 1ffffffff1c40fc4 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888125707000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000562f6e22d168 CR3: 000000000e33c000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/kernel/process.c:767 [inline] default_idle+0x9/0x20 arch/x86/kernel/process.c:768 default_idle_call+0x70/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x2e0/0x530 kernel/sched/idle.c:355 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:454 rest_init+0x2de/0x300 init/main.c:717 start_kernel+0x392/0x3e0 init/main.c:1175 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x137/0x1b0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x157