INFO: task syz-executor:4185 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:21104 pid: 4185 ppid: 1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503 wait_on_page_bit_common+0x83b/0xe50 mm/filemap.c:1356 lock_page include/linux/pagemap.h:625 [inline] truncate_inode_pages_range+0xa24/0xfe0 mm/truncate.c:394 evict+0x4dc/0x8d0 fs/inode.c:649 dispose_list fs/inode.c:680 [inline] evict_inodes+0x60c/0x6a0 fs/inode.c:734 generic_shutdown_super+0x93/0x300 fs/super.c:454 kill_block_super+0x7c/0xe0 fs/super.c:1427 deactivate_locked_super+0x93/0xf0 fs/super.c:335 cleanup_mnt+0x42d/0x4e0 fs/namespace.c:1148 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fdd14e3fa57 RSP: 002b:00007ffcbfca2688 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fdd14ed4048 RCX: 00007fdd14e3fa57 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffcbfca2740 RBP: 00007ffcbfca2740 R08: 00007ffcbfca3740 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffcbfca37d0 R13: 00007fdd14ed4048 R14: 000000000001f78b R15: 00007ffcbfca3810 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c31eb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 4 locks held by kworker/u4:3/301: 2 locks held by udevd/3561: #0: ffff888020049518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915 #1: ffff888020286468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2071 2 locks held by getty/3951: #0: ffff88814d461098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002d032e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158 1 lock held by udevd/4175: #0: ffff888020049518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820 1 lock held by syz-executor/4185: #0: ffff8880247060e0 (&type->s_umount_key#102){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365 2 locks held by kworker/1:17/5260: #0: ffff888016c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1 #1: ffffc900030a7d00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285 3 locks held by kworker/0:14/6579: #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1 #1: ffffc900034afd00 (fqdir_free_work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285 #2: ffffffff8c3234b0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4c0 kernel/rcu/tree.c:4043 1 lock held by syz.0.2546/11138: #0: ffff888020049518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820 ============================================= 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 03/18/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 301 Comm: kworker/u4:3 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Workqueue: netns cleanup_net RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:91 [inline] RIP: 0010:lock_release+0x107/0x8a0 kernel/locking/lockdep.c:5636 Code: 84 b9 04 00 00 65 8b 05 57 e5 a4 7e 85 c0 0f 85 aa 04 00 00 65 48 8b 1d c7 db a4 7e 4c 8d b3 ec 0a 00 00 4c 89 f0 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 47 05 00 00 41 83 3e 00 0f 85 7d 04 00 RSP: 0018:ffffc90002d7f900 EFLAGS: 00000a03 RAX: 1ffff11003b7b8cd RBX: ffff88801dbdbb80 RCX: 58678a58f94b2300 RDX: 0000000000000000 RSI: ffffffff8a79fe20 RDI: ffffffff8a79fde0 RBP: ffffc90002d7fa10 R08: ffffffff8d89f06f R09: 1ffffffff1b13e0d R10: dffffc0000000000 R11: fffffbfff1b13e0e R12: 1ffff920005aff2c R13: dffffc0000000000 R14: ffff88801dbdc66c R15: 0000000000000008 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f045bce1b60 CR3: 0000000073acf000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_unlock include/linux/rcupdate.h:773 [inline] inet_twsk_purge+0x7a7/0x840 net/ipv4/inet_timewait_sock.c:309 tcp_sk_exit_batch+0x28/0x90 net/ipv4/tcp_ipv4.c:3234 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x791/0xba0 net/core/net_namespace.c:635 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 vkms_vblank_simulate: vblank timer overrun