INFO: task syz-executor:4195 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:21840 pid: 4195 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: 0033:0x7f956e7d6a57 RSP: 002b:00007ffffa350978 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f956e86b048 RCX: 00007f956e7d6a57 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffffa350a30 RBP: 00007ffffa350a30 R08: 00007ffffa351a30 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffffa351ac0 R13: 00007f956e86b048 R14: 000000000001e986 R15: 00007ffffa351b00 Showing all locks held in the system: 4 locks held by kworker/1:1/23: #0: ffff888141fef538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1 #1: ffffc90000ddfd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285 #2: ffff88802448b220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline] #2: ffff88802448b220 (&dev->mutex){....}-{3:3}, at: hub_event+0x19f/0x55e0 drivers/usb/core/hub.c:5827 #3: ffff88802379a220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline] #3: ffff88802379a220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x85/0x480 drivers/base/dd.c:954 1 lock held by khungtaskd/27: #0: ffffffff8c31eaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/3950: #0: ffff88802c286098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158 1 lock held by syz-executor/4193: #0: ffff88807c27a0e0 (&type->s_umount_key#76){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365 1 lock held by syz-executor/4195: #0: ffff88807d00e0e0 (&type->s_umount_key#76){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365 4 locks held by udevd/4382: #0: ffff88807b1fd1c8 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xad/0xd50 fs/seq_file.c:182 #1: ffff888060b11088 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x51/0x3c0 fs/kernfs/file.c:112 #2: ffff8880637d41d8 (kn->active#32){++++}-{0:0}, at: kernfs_seq_start+0x71/0x3c0 fs/kernfs/file.c:113 #3: ffff88802379a220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline] #3: ffff88802379a220 (&dev->mutex){....}-{3:3}, at: uevent_show+0x17a/0x330 drivers/base/core.c:2408 ============================================= 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: 4883 Comm: kworker/1:18 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Workqueue: events nsim_dev_trap_report_work RIP: 0010:lock_acquire+0x18e/0x400 kernel/locking/lockdep.c:5623 Code: 5f 08 65 ff 05 03 78 a5 7e 45 31 c9 41 f7 c6 00 02 00 00 41 0f 94 c1 4c 89 e7 8b 74 24 1c 89 da 48 8b 4c 24 28 4c 8b 44 24 30 <6a> 00 6a 00 ff 75 10 ff 74 24 38 e8 a2 03 00 00 48 83 c4 20 48 c7 RSP: 0018:ffffc9000329f740 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880b9137270 RBP: ffffc9000329f860 R08: 0000000000000001 R09: 0000000000000001 R10: dffffc0000000000 R11: fffffbfff1b13c6e R12: ffff8880b9137270 R13: 1ffff92000653ef4 R14: 0000000000000046 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c3cf5a6 CR3: 000000007c268000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: local_lock_acquire+0x34/0x170 include/linux/local_lock_internal.h:29 crng_make_state+0x1cf/0x670 drivers/char/random.c:367 _get_random_bytes+0xfc/0x250 drivers/char/random.c:405 eth_random_addr include/linux/etherdevice.h:225 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:671 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:721 [inline] nsim_dev_trap_report_work+0x346/0xb40 drivers/net/netdevsim/dev.c:762 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