INFO: task syz-executor:5856 blocked for more than 143 seconds. Not tainted 6.14.0-next-20250404-syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:20520 pid:5856 tgid:5856 ppid:1 task_flags:0x40054c flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b88/0x5240 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x163/0x360 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+0x805/0x10c0 kernel/locking/mutex.c:746 rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3774 netdev_run_todo+0x380/0xf30 net/core/dev.c:11283 tun_detach drivers/net/tun.c:639 [inline] tun_chr_close+0x137/0x1b0 drivers/net/tun.c:3390 __fput+0x3e9/0x9f0 fs/file_table.c:465 task_work_run+0x251/0x310 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xa0d/0x27e0 kernel/exit.c:953 do_group_exit+0x207/0x2c0 kernel/exit.c:1102 get_signal+0x1696/0x1730 kernel/signal.c:3034 arch_do_signal_or_restart+0x98/0x840 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbaaeb8bb7c RSP: 002b:00007fffb6735780 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: fffffffffffffe00 RBX: 0000000000000003 RCX: 00007fbaaeb8bb7c RDX: 0000000000000030 RSI: 00007fffb6735840 RDI: 00000000000000f9 RBP: 00007fffb67357ec R08: 0000000000000000 R09: 0079746972756365 R10: 00007fbaaed797e0 R11: 0000000000000246 R12: 0000000000000020 R13: 000000000000004a R14: 00000000000295dd R15: 00007fffb6735840 INFO: task syz.1.129:6595 blocked for more than 144 seconds. Not tainted 6.14.0-next-20250404-syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.129 state:D stack:24904 pid:6595 tgid:6573 ppid:5841 task_flags:0x40044c flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b88/0x5240 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x163/0x360 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+0x805/0x10c0 kernel/locking/mutex.c:746 rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3774 netdev_run_todo+0x380/0xf30 net/core/dev.c:11283 tun_detach drivers/net/tun.c:639 [inline] tun_chr_close+0x137/0x1b0 drivers/net/tun.c:3390 __fput+0x3e9/0x9f0 fs/file_table.c:465 task_work_run+0x251/0x310 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xa0d/0x27e0 kernel/exit.c:953 do_group_exit+0x207/0x2c0 kernel/exit.c:1102 get_signal+0x1696/0x1730 kernel/signal.c:3034 arch_do_signal_or_restart+0x98/0x840 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd99f58d169 RSP: 002b:00007fd9a046a038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: 0000000000010106 RBX: 00007fd99f7a6080 RCX: 00007fd99f58d169 RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003 RBP: 00007fd99f60e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fd99f7a6080 R15: 00007ffe24e8f418 INFO: task syz.5.142:6625 blocked for more than 145 seconds. Not tainted 6.14.0-next-20250404-syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.142 state:D stack:24040 pid:6625 tgid:6625 ppid:6068 task_flags:0x40044c flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b88/0x5240 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x163/0x360 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+0x805/0x10c0 kernel/locking/mutex.c:746 rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3774 netdev_run_todo+0x380/0xf30 net/core/dev.c:11283 tun_detach drivers/net/tun.c:639 [inline] tun_chr_close+0x137/0x1b0 drivers/net/tun.c:3390 __fput+0x3e9/0x9f0 fs/file_table.c:465 task_work_run+0x251/0x310 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xa0d/0x27e0 kernel/exit.c:953 do_group_exit+0x207/0x2c0 kernel/exit.c:1102 get_signal+0x1696/0x1730 kernel/signal.c:3034 arch_do_signal_or_restart+0x98/0x840 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f189758d169 RSP: 002b:00007ffd13c3c4c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffdfc RBX: 000000000002e415 RCX: 00007f189758d169 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f18977a5fac RBP: 0000000000000fd2 R08: 7fffffffffffffff R09: 0000000113c3c7bf R10: 00007ffd13c3c5c0 R11: 0000000000000246 R12: 00007f18977a5fac R13: 00007ffd13c3c5c0 R14: 000000000002f3e7 R15: 00007ffd13c3c5e0 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8ed3e440 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ed3e440 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8ed3e440 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764 2 locks held by kworker/u8:5/1001: 4 locks held by kworker/u8:9/3019: #0: ffff88801bef6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801bef6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc9000c057c60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000c057c60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff900f2910 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17c/0xd60 net/core/net_namespace.c:608 #3: ffffffff8ed43840 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3774 1 lock held by klogd/5204: 2 locks held by getty/5600: #0: ffff8880363ba0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5846: #0: ffffffff8ed43840 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3774 2 locks held by syz-executor/5850: #0: ffff888028dc60e0 (&type->s_umount_key#58){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff888028dc60e0 (&type->s_umount_key#58){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888028dc60e0 (&type->s_umount_key#58){+.+.}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8ed43840 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3774 1 lock held by syz-executor/5856: #0: ffffffff8ed43840 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3774 4 locks held by kworker/0:3/5891: 1 lock held by syz.1.129/6595: #0: ffffffff8ed43840 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3774 1 lock held by syz.5.142/6625: #0: ffffffff8ed43840 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3774 4 locks held by syz-executor/6643: #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x23f/0xd10 fs/read_write.c:680 #1: ffff88802a844488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e2/0x510 fs/kernfs/file.c:325 #2: ffff888143f732d8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x206/0x510 fs/kernfs/file.c:326 #3: ffffffff8f998ca8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfe/0x490 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/6646: #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x23f/0xd10 fs/read_write.c:680 #1: ffff88802a844088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e2/0x510 fs/kernfs/file.c:325 #2: ffff888143f732d8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x206/0x510 fs/kernfs/file.c:326 #3: ffffffff8f998ca8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfe/0x490 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/6647: #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x23f/0xd10 fs/read_write.c:680 #1: ffff88806cf44088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e2/0x510 fs/kernfs/file.c:325 #2: ffff888143f732d8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x206/0x510 fs/kernfs/file.c:326 #3: ffffffff8f998ca8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfe/0x490 drivers/net/netdevsim/bus.c:216 7 locks held by syz-executor/6651: #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x23f/0xd10 fs/read_write.c:680 #1: ffff88805b2dc888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e2/0x510 fs/kernfs/file.c:325 #2: ffff888143f732d8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x206/0x510 fs/kernfs/file.c:326 #3: ffffffff8f998ca8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfe/0x490 drivers/net/netdevsim/bus.c:216 #4: ffff88805c9f40e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #4: ffff88805c9f40e8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff88805c9f40e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293 #5: ffff88807f00c250 (&devlink->lock_key#4){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1675 #6: ffffffff8ed43840 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3774 4 locks held by syz-executor/6966: #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x23f/0xd10 fs/read_write.c:680 #1: ffff888055488088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e2/0x510 fs/kernfs/file.c:325 #2: ffff888143f732d8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x206/0x510 fs/kernfs/file.c:326 #3: ffffffff8f998ca8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfe/0x490 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/6969: #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x23f/0xd10 fs/read_write.c:680 #1: ffff888033fed488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e2/0x510 fs/kernfs/file.c:325 #2: ffff888143f732d8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x206/0x510 fs/kernfs/file.c:326 #3: ffffffff8f998ca8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfe/0x490 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/7011: #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x23f/0xd10 fs/read_write.c:680 #1: ffff888045dca088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e2/0x510 fs/kernfs/file.c:325 #2: ffff888143f732d8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x206/0x510 fs/kernfs/file.c:326 #3: ffffffff8f998ca8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfe/0x490 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/7014: #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x23f/0xd10 fs/read_write.c:680 #1: ffff888045dd5088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e2/0x510 fs/kernfs/file.c:325 #2: ffff888143f732d8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x206/0x510 fs/kernfs/file.c:326 #3: ffffffff8f998ca8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfe/0x490 drivers/net/netdevsim/bus.c:216 1 lock held by syz.6.161/7018: #0: ffffffff8ed43840 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3774 4 locks held by syz-executor/7037: #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x23f/0xd10 fs/read_write.c:680 #1: ffff888046fc2888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e2/0x510 fs/kernfs/file.c:325 #2: ffff888143f732d8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x206/0x510 fs/kernfs/file.c:326 #3: ffffffff8f998ca8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfe/0x490 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/7051: #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x23f/0xd10 fs/read_write.c:680 #1: ffff88807f118088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e2/0x510 fs/kernfs/file.c:325 #2: ffff888143f732d8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x206/0x510 fs/kernfs/file.c:326 #3: ffffffff8f998ca8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfe/0x490 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/7052: #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x23f/0xd10 fs/read_write.c:680 #1: ffff888094facc88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e2/0x510 fs/kernfs/file.c:325 #2: ffff888143f732d8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x206/0x510 fs/kernfs/file.c:326 #3: ffffffff8f998ca8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfe/0x490 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/7055: #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x23f/0xd10 fs/read_write.c:680 #1: ffff88807f119488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e2/0x510 fs/kernfs/file.c:325 #2: ffff888143f732d8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x206/0x510 fs/kernfs/file.c:326 #3: ffffffff8f998ca8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfe/0x490 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/7060: #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x23f/0xd10 fs/read_write.c:680 #1: ffff888094886c88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e2/0x510 fs/kernfs/file.c:325 #2: ffff888143f732d8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x206/0x510 fs/kernfs/file.c:326 #3: ffffffff8f998ca8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfe/0x490 drivers/net/netdevsim/bus.c:216 4 locks held by syz-executor/7093: #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #0: ffff8880367b0420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x23f/0xd10 fs/read_write.c:680 #1: ffff888093f87c88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e2/0x510 fs/kernfs/file.c:325 #2: ffff888143f732d8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x206/0x510 fs/kernfs/file.c:326 #3: ffffffff8f998ca8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfe/0x490 drivers/net/netdevsim/bus.c:216 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-next-20250404-syzkaller #0 PREEMPT(full) 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+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 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+0x1058/0x10a0 kernel/hung_task.c:437 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 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: 6947 Comm: kworker/0:11 Not tainted 6.14.0-next-20250404-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: wg-crypt-wg2 wg_packet_tx_worker RIP: 0010:check_preemption_disabled+0x4/0x120 lib/smp_processor_id.c:13 Code: 8c 48 c7 c6 40 e0 a1 8c eb 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 57 41 56 <41> 55 41 54 53 48 83 ec 10 49 c7 c4 20 10 69 93 65 49 8b 04 24 48 RSP: 0018:ffffc90000006470 EFLAGS: 00000086 RAX: 0000000000000001 RBX: ffffffff8ed3e440 RCX: 0dc4a45b7fcbca00 RDX: 0000000000000000 RSI: ffffffff8e50585c RDI: ffffffff8ca1e060 RBP: ffffffff93691020 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000002 R14: 0000000000000246 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888124f8f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5825902e10 CR3: 0000000034f20000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:472 [inline] lock_acquire+0x126/0x2f0 kernel/locking/lockdep.c:5868 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xd5/0x23b0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11e/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x11a/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x9d/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4331 [inline] __kmalloc_node_track_caller_noprof+0x295/0x4d0 mm/slub.c:4350 __do_krealloc mm/slub.c:4908 [inline] krealloc_noprof+0x10f/0x300 mm/slub.c:4961 nf_ct_ext_add+0x1a8/0x410 net/netfilter/nf_conntrack_extend.c:117 nf_ct_labels_ext_add include/net/netfilter/nf_conntrack_labels.h:45 [inline] init_conntrack+0x6c1/0x1010 net/netfilter/nf_conntrack_core.c:1780 resolve_normal_ct net/netfilter/nf_conntrack_core.c:1882 [inline] nf_conntrack_in+0xd61/0x18c0 net/netfilter/nf_conntrack_core.c:2034 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc8/0x220 net/netfilter/core.c:626 nf_hook+0x2c9/0x460 include/linux/netfilter.h:269 __ip_local_out+0x50f/0x610 net/ipv4/ip_output.c:118 ip_local_out+0x26/0x70 net/ipv4/ip_output.c:127 synproxy_send_client_synack+0x8ea/0xf70 net/netfilter/nf_synproxy_core.c:484 nft_synproxy_eval_v4+0x3cc/0x610 net/netfilter/nft_synproxy.c:59 nft_synproxy_do_eval+0x36a/0xa90 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline] nft_do_chain+0x4b2/0x1db0 net/netfilter/nf_tables_core.c:285 nft_do_chain_inet+0x41f/0x6b0 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc8/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x29b/0x450 include/linux/netfilter.h:312 NF_HOOK+0x3a0/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5891 [inline] __netif_receive_skb+0x2c9/0x670 net/core/dev.c:6004 process_backlog+0x664/0x15c0 net/core/dev.c:6356 __napi_poll+0xcb/0x480 net/core/dev.c:7328 napi_poll net/core/dev.c:7392 [inline] net_rx_action+0x89d/0x1240 net/core/dev.c:7514 handle_softirqs+0x2d6/0x9b0 kernel/softirq.c:579 do_softirq+0x11f/0x1e0 kernel/softirq.c:480 __local_bh_enable_ip+0x1be/0x200 kernel/softirq.c:407 wg_packet_create_data_done drivers/net/wireguard/send.c:247 [inline] wg_packet_tx_worker+0x160/0x810 drivers/net/wireguard/send.c:276 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd50 kernel/workqueue.c:3400 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245