INFO: task syz.1.54:6244 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.54 state:D stack:24824 pid:6244 tgid:6234 ppid:5799 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1480/0x50a0 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7241 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked+0x1dfe/0x25e0 kernel/locking/rtmutex.c:1760 __rwbase_read_lock+0xbc/0x180 kernel/locking/rwbase_rt.c:114 rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline] __down_read kernel/locking/rwsem.c:1466 [inline] down_read+0x127/0x1f0 kernel/locking/rwsem.c:1539 __super_lock fs/super.c:59 [inline] super_lock+0x2a9/0x3b0 fs/super.c:121 __iterate_supers+0x126/0x290 fs/super.c:923 quota_sync_all fs/quota/quota.c:69 [inline] __do_sys_quotactl fs/quota/quota.c:938 [inline] __se_sys_quotactl+0x353/0x950 fs/quota/quota.c:917 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa9753df749 RSP: 002b:00007fa973625038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 00007fa975636090 RCX: 00007fa9753df749 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000102 RBP: 00007fa975463f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa975636128 R14: 00007fa975636090 R15: 00007ffe54244c08 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8d5ae8c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d5ae8c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8d5ae8c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/1:2/805: 4 locks held by kworker/u8:11/1410: #0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc90005607b80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90005607b80 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffffffff8e898600 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x7b0 net/core/net_namespace.c:670 #3: ffffffff8e8a5738 (rtnl_mutex){+.+.}-{4:4}, at: wg_destruct+0x25/0x310 drivers/net/wireguard/device.c:246 2 locks held by dhcpcd/5465: #0: ffffffff8e889798 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x5f1/0x790 net/socket.c:1337 #1: ffffffff8e8a5738 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0xd0/0x650 net/8021q/vlan.c:579 2 locks held by getty/5559: #0: ffff88814deef0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x44f/0x1460 drivers/tty/n_tty.c:2211 4 locks held by syz-executor/5803: 1 lock held by syz.1.54/6244: #0: ffff88805cdfc0d0 (&type->s_umount_key#68){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff88805cdfc0d0 (&type->s_umount_key#68){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 1 lock held by syz-executor/6253: #0: ffff88804e1080d0 (&type->s_umount_key#32){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88804e1080d0 (&type->s_umount_key#32){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88804e1080d0 (&type->s_umount_key#32){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 1 lock held by syz.8.146/7116: #0: ffff88805cdfc0d0 (&type->s_umount_key#68){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff88805cdfc0d0 (&type->s_umount_key#68){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 1 lock held by syz-executor/7173: 2 locks held by syz-executor/7273: #0: ffffffff8e021c88 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e021c88 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e021c88 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8e8a5738 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8e8a5738 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8e8a5738 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071 2 locks held by syz-executor/7584: #0: ffffffff8e898600 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x3cc/0x570 net/core/net_namespace.c:577 #1: ffffffff8e8a5738 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x2ab/0x800 net/ipv4/ip_tunnel.c:1146 3 locks held by syz.6.219/7628: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [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:346 [inline] watchdog+0xf95/0xfe0 kernel/hung_task.c:515 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6984 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:page_ext_data include/linux/page_ext.h:102 [inline] RIP: 0010:get_page_owner mm/page_owner.c:152 [inline] RIP: 0010:__update_page_owner_free_handle+0x193/0x470 mm/page_owner.c:285 Code: 87 8e 01 00 00 e8 3d 72 98 ff 4c 89 f7 4c 8b 6c 24 28 4c 89 ee e8 cd 74 98 ff 4d 39 f5 0f 84 2c 02 00 00 48 8b 2d 5d 6c 46 0b <4c> 01 fd 83 3c 24 00 4c 89 7c 24 38 74 37 e8 0a 72 98 ff 4c 89 ff RSP: 0018:ffffc90004c47750 EFLAGS: 00000202 RAX: ffffffff8227f1b3 RBX: dffffc0000000000 RCX: ffff88801af8bc80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000000c R11: ffffffff81ac4310 R12: 0000000000064a56 R13: 0000000000000001 R14: 0000000000000000 R15: ffff88801c573a90 FS: 0000000000000000(0000) GS:ffff888126d01000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd49870eb8 CR3: 000000005295e000 CR4: 00000000003526f0 Call Trace: __reset_page_owner+0x85/0x1f0 mm/page_owner.c:321 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xfe1/0x1170 mm/page_alloc.c:2943 vfree+0x2ad/0x470 mm/vmalloc.c:3466 kcov_put kernel/kcov.c:439 [inline] kcov_close+0x2e/0x60 kernel/kcov.c:535 __fput+0x45b/0xa80 fs/file_table.c:468 task_work_run+0x1d4/0x260 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x6c5/0x2310 kernel/exit.c:971 do_group_exit+0x21c/0x2d0 kernel/exit.c:1112 get_signal+0x125d/0x1310 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2d0/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f42132fe1ff Code: Unable to access opcode bytes at 0x7f42132fe1d5. RSP: 002b:00007ffd3d4df880 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: 0000000000000003 RBX: 0000000000000005 RCX: 00007f42132fe1ff RDX: 0000000000000003 RSI: 00007ffd3d4df8d0 RDI: 0000000000000005 RBP: 00007f42133852ef R08: 0000000000000000 R09: 00007ffd3d4df6d7 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 00007ffd3d4df8d0 R14: 00007f4214084620 R15: 0000000000000003