INFO: task syz-executor:18643 blocked for more than 143 seconds. Not tainted 6.15.0-rc7-syzkaller-00175-g0f8c0258bf04 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:22232 pid:18643 tgid:18643 ppid:1 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 io_schedule+0x81/0xe0 kernel/sched/core.c:7742 folio_wait_bit_common+0x6b0/0xb90 mm/filemap.c:1317 __folio_lock mm/filemap.c:1664 [inline] folio_lock include/linux/pagemap.h:1137 [inline] __filemap_get_folio+0x139/0xaf0 mm/filemap.c:1917 truncate_inode_pages_range+0x3ed/0xda0 mm/truncate.c:388 evict+0x517/0x9c0 fs/inode.c:812 dispose_list fs/inode.c:852 [inline] evict_inodes+0x636/0x6c0 fs/inode.c:906 generic_shutdown_super+0x9a/0x2c0 fs/super.c:627 kill_block_super+0x44/0x90 fs/super.c:1710 deactivate_locked_super+0xbc/0x130 fs/super.c:473 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1431 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work+0x5e/0x80 include/linux/resume_user_mode.h:50 exit_to_user_mode_loop kernel/entry/common.c:114 [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+0x9a/0x120 kernel/entry/common.c:218 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa2e338fc97 RSP: 002b:00007ffe265b6218 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fa2e341089d RCX: 00007fa2e338fc97 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe265b62d0 RBP: 00007ffe265b62d0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe265b7360 R13: 00007fa2e341089d R14: 00000000000d3028 R15: 00007ffe265b73a0 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 1 lock held by udevd/5193: 2 locks held by getty/5582: #0: ffff88814d0d00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002ffe2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by udevd/14591: 1 lock held by syz-executor/18643: #0: ffff8880334240e0 (&type->s_umount_key#97){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff8880334240e0 (&type->s_umount_key#97){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff8880334240e0 (&type->s_umount_key#97){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505 2 locks held by syz.7.11204/31710: #0: ffff8880b8839b58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605 #1: ffff8880b8823b08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc7-syzkaller-00175-g0f8c0258bf04 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4e/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 15337 Comm: kworker/u8:5 Not tainted 6.15.0-rc7-syzkaller-00175-g0f8c0258bf04 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:debug_smp_processor_id+0x0/0x20 lib/smp_processor_id.c:59 Code: c7 40 8f ff 8d 4c 89 f6 e8 fd 7f 97 f9 e9 66 ff ff ff cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 c7 c7 a0 f5 c1 8b 48 c7 c6 e0 f5 c1 8b eb 1c 66 66 RSP: 0018:ffffc9000c49f7d8 EFLAGS: 00000046 RAX: 1178da6cf202bf00 RBX: ffff8880b8935fb0 RCX: 0000000000000000 RDX: 0000000000000040 RSI: 0000000000000000 RDI: ffffc9000c49f760 RBP: ffffc9000c49f8d0 R08: ffffc9000c49f75f R09: ffffc9000c49f720 R10: dffffc0000000000 R11: fffff52001893eec R12: dffffc0000000000 R13: ffff8880b8935f90 R14: 1ffff11017126bf6 R15: 000000000000001f FS: 0000000000000000(0000) GS:ffff8881261c2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1f1737d2d8 CR3: 000000001bff7000 CR4: 0000000000350ef0 Call Trace: crng_make_state+0x25a/0x700 drivers/char/random.c:393 _get_random_bytes+0xd5/0x210 drivers/char/random.c:406 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:775 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline] nsim_dev_trap_report_work+0x69e/0xb80 drivers/net/netdevsim/dev.c:851 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xade/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4e/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245