INFO: task syz-executor:4277 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:21952 pid:4277 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 io_schedule+0x7c/0xd0 kernel/sched/core.c:8797 folio_wait_bit_common+0x6e1/0xf60 mm/filemap.c:1324 truncate_inode_pages_range+0x9a2/0xff0 mm/truncate.c:422 evict+0x498/0x870 fs/inode.c:707 dispose_list fs/inode.c:738 [inline] evict_inodes+0x604/0x690 fs/inode.c:792 generic_shutdown_super+0x93/0x340 fs/super.c:480 kill_block_super+0x7c/0xe0 fs/super.c:1470 deactivate_locked_super+0x93/0xf0 fs/super.c:332 cleanup_mnt+0x463/0x4f0 fs/namespace.c:1191 task_work_run+0x1ca/0x250 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f3300790a77 RSP: 002b:00007ffc399004d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f3300813d7d RCX: 00007f3300790a77 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc39900590 RBP: 00007ffc39900590 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc39901620 R13: 00007f3300813d7d R14: 000000000001506c R15: 00007ffc39901660 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2b630 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8cb2be50 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/27: #0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 2 locks held by getty/4029: #0: ffff88814d3b4098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198 1 lock held by syz-executor/4277: #0: ffff88807dafa0e0 (&type->s_umount_key#60){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362 1 lock held by syz-executor/4838: #0: ffff8880539440e0 (&type->s_umount_key#60){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362 1 lock held by syz.0.2118/9047: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3f4/0x470 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xeee/0xf30 kernel/hung_task.c:377 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 9047 Comm: syz.0.2118 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:in_lock_functions+0x0/0x20 kernel/locking/spinlock.c:412 Code: cd fe ff ff 48 c7 c1 c0 27 b2 92 80 e1 07 80 c1 03 38 c1 0f 8c 77 ff ff ff 48 c7 c7 c0 27 b2 92 e8 95 dc 6c 00 e9 66 ff ff ff <48> 81 ff a0 e5 21 8a 0f 93 c0 48 81 ff 6f 0e 22 8a 0f 92 c1 20 c1 RSP: 0018:ffffc900049b6a58 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff96be9101 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900049b6b10 R08: ffff888074a60000 R09: 0000000000000002 R10: 0000000000000001 R11: 0000000000000002 R12: dffffc0000000000 R13: ffff888023ea7140 R14: 0000000000000a06 R15: dffffc0000000000 FS: 00007f31df2146c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd5609b9358 CR3: 0000000024bb9000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: get_lock_parent_ip include/linux/ftrace.h:953 [inline] preempt_latency_start kernel/sched/core.c:5691 [inline] preempt_count_add+0x9a/0x190 kernel/sched/core.c:5716 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:109 [inline] _raw_spin_lock_irqsave+0x89/0xf0 kernel/locking/spinlock.c:162 __debug_check_no_obj_freed lib/debugobjects.c:968 [inline] debug_check_no_obj_freed+0x136/0x530 lib/debugobjects.c:1009 slab_free_hook mm/slub.c:1704 [inline] slab_free_freelist_hook+0xd2/0x1a0 mm/slub.c:1755 slab_free mm/slub.c:3687 [inline] kmem_cache_free+0xf7/0x290 mm/slub.c:3709 netlink_broadcast+0xfd6/0x10d0 net/netlink/af_netlink.c:1521 uevent_net_broadcast_tagged lib/kobject_uevent.c:372 [inline] kobject_uevent_net_broadcast+0x497/0x530 lib/kobject_uevent.c:412 kobject_uevent_env+0x54c/0x8a0 lib/kobject_uevent.c:608 rx_queue_add_kobject net/core/net-sysfs.c:1072 [inline] net_rx_queue_update_kobjects+0x23f/0x4a0 net/core/net-sysfs.c:1112 register_queue_kobjects net/core/net-sysfs.c:1772 [inline] netdev_register_kobject+0x223/0x310 net/core/net-sysfs.c:2017 register_netdevice+0x12b9/0x1aa0 net/core/dev.c:10204 wg_newlink+0x46d/0x730 drivers/net/wireguard/device.c:372 rtnl_newlink_create net/core/rtnetlink.c:3422 [inline] __rtnl_newlink net/core/rtnetlink.c:3642 [inline] rtnl_newlink+0x14c4/0x1ff0 net/core/rtnetlink.c:3655 rtnetlink_rcv_msg+0x79b/0xed0 net/core/rtnetlink.c:6150 netlink_rcv_skb+0x1de/0x420 net/netlink/af_netlink.c:2511 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x89e/0xbc0 net/netlink/af_netlink.c:1872 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x59b/0x970 net/socket.c:2519 ___sys_sendmsg+0x21c/0x290 net/socket.c:2573 __sys_sendmsg net/socket.c:2602 [inline] __do_sys_sendmsg net/socket.c:2611 [inline] __se_sys_sendmsg+0x19e/0x270 net/socket.c:2609 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f31de38f749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f31df214038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f31de5e5fa0 RCX: 00007f31de38f749 RDX: 0000000004000010 RSI: 0000200000000280 RDI: 0000000000000003 RBP: 00007f31de413f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f31de5e6038 R14: 00007f31de5e5fa0 R15: 00007ffc2119eaa8 vkms_vblank_simulate: vblank timer overrun