INFO: task syz.9.13009:20490 blocked for more than 143 seconds. Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.9.13009 state:D stack:26920 pid:20490 tgid:20490 ppid:17083 task_flags:0x40044c flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5351 [inline] __schedule+0x1737/0x4d30 kernel/sched/core.c:6954 __schedule_loop kernel/sched/core.c:7036 [inline] schedule+0x165/0x360 kernel/sched/core.c:7051 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7108 rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1088 __down_read_common kernel/locking/rwsem.c:1263 [inline] __down_read kernel/locking/rwsem.c:1276 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1541 mmap_read_lock include/linux/mmap_lock.h:412 [inline] exit_mm+0xcc/0x2c0 kernel/exit.c:557 do_exit+0x648/0x2300 kernel/exit.c:947 do_group_exit+0x21c/0x2d0 kernel/exit.c:1100 get_signal+0x1286/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f373798e9e3 RSP: 002b:00007ffce88733a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: fffffffffffffffc RBX: 00007f3735ff76c0 RCX: 00007f373798e9e3 RDX: 0000000000000000 RSI: 0000000000021000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000 R10: 0000000000020022 R11: 0000000000000246 R12: 00007ffce8873500 R13: ffffffffffffffc0 R14: 0000000000001000 R15: 0000000000000000 Showing all locks held in the system: 5 locks held by kworker/1:0/24: 1 lock held by khungtaskd/31: #0: ffffffff8e53d8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e53d8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e53d8a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 2 locks held by kworker/1:1/44: #0: ffff88801a880d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801a880d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90000b47bc0 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90000b47bc0 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 2 locks held by getty/27734: #0: ffff88814ded60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003a752f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by syz-executor/11656: 3 locks held by syz-executor/11688: #0: ffff888065880dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:499 [inline] #0: ffff888065880dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x510 net/bluetooth/hci_core.c:2715 #1: ffff8880658800b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5282 #2: ffffffff8faa0e68 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2058 [inline] #2: ffffffff8faa0e68 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 net/bluetooth/hci_conn.c:2561 2 locks held by kworker/u8:3/11760: 1 lock held by syz.9.13009/20490: #0: ffff88806a4fed60 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:412 [inline] #0: ffff88806a4fed60 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0xcc/0x2c0 kernel/exit.c:557 1 lock held by syz.9.13009/20491: 4 locks held by syz-executor/20808: #0: ffff888042be0dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:499 [inline] #0: ffff888042be0dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x510 net/bluetooth/hci_core.c:2715 #1: ffff888042be00b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5282 #2: ffffffff8faa0e68 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2058 [inline] #2: ffffffff8faa0e68 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 net/bluetooth/hci_conn.c:2561 #3: ffff8880690ccb38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 net/bluetooth/l2cap_core.c:1762 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf93/0xfe0 kernel/hung_task.c:491 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 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: 20491 Comm: syz.9.13009 Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:__sanitizer_cov_trace_cmp8+0x0/0x90 kernel/kcov.c:293 Code: 7c 11 10 48 89 74 11 18 48 89 44 11 20 e9 88 56 c2 09 cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 50 e7 92 65 8b 15 a8 4c RSP: 0018:ffffc9000af3f278 EFLAGS: 00000293 RAX: 0000000000000004 RBX: ffffffff8cdac6a1 RCX: 000000008cdac701 RDX: ffffc90011f08000 RSI: 0000000000000010 RDI: 0000000000000003 RBP: ffffc9000af3f450 R08: ffff88807f140000 R09: 0000000000000004 R10: 0000000000000003 R11: 0000000000000002 R12: 0000000000000003 R13: 0000000000b0e000 R14: 0000000000000010 R15: ffffffff8cdac701 FS: 00007f37387f06c0(0000) GS:ffff8881258ab000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff801ce7d60 CR3: 000000004262e000 CR4: 00000000003526f0 Call Trace: mas_validate_gaps lib/maple_tree.c:7332 [inline] mt_validate+0x22d4/0x4380 lib/maple_tree.c:7612 validate_mm+0xb6/0x4b0 mm/vma.c:651 vma_link+0x366/0x450 mm/vma.c:1799 copy_vma+0x70c/0x940 mm/vma.c:1880 copy_vma_and_data mm/mremap.c:1184 [inline] move_vma+0x81f/0x1840 mm/mremap.c:1282 mremap_to+0x6d6/0x7a0 mm/mremap.c:1406 remap_move mm/mremap.c:1863 [inline] do_mremap mm/mremap.c:1906 [inline] __do_sys_mremap mm/mremap.c:1970 [inline] __se_sys_mremap+0xa0b/0xef0 mm/mremap.c:1938 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f373798e9a9 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:00007f37387f0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000019 RAX: ffffffffffffffda RBX: 00007f3737bb5fa0 RCX: 00007f373798e9a9 RDX: 0000000000003000 RSI: 0000000000003000 RDI: 0000200000278000 RBP: 00007f3737a10d69 R08: 0000200000b14000 R09: 0000000000000000 R10: 0000000000000007 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f3737bb5fa0 R15: 00007ffce8873408