INFO: task syz.2.2197:14480 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.2197 state:D stack:26728 pid:14480 tgid:14476 ppid:5846 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083 rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1261 [inline] __down_read kernel/locking/rwsem.c:1274 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1539 i_mmap_lock_read include/linux/fs.h:568 [inline] __rmap_walk_file+0x227/0x620 mm/rmap.c:2905 remove_migration_ptes mm/migrate.c:471 [inline] unmap_and_move_huge_page mm/migrate.c:1520 [inline] migrate_hugetlbs mm/migrate.c:1641 [inline] migrate_pages+0xc98/0x2930 mm/migrate.c:2080 do_mbind mm/mempolicy.c:1539 [inline] kernel_mbind mm/mempolicy.c:1682 [inline] __do_sys_mbind mm/mempolicy.c:1756 [inline] __se_sys_mbind+0xa47/0xc40 mm/mempolicy.c:1752 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdbeaf8eec9 RSP: 002b:00007fdbebed9038 EFLAGS: 00000246 ORIG_RAX: 00000000000000ed RAX: ffffffffffffffda RBX: 00007fdbeb1e6090 RCX: 00007fdbeaf8eec9 RDX: 0000000000000001 RSI: 0000000000600000 RDI: 0000200000000000 RBP: 00007fdbeb011f91 R08: 0000000000000000 R09: 0000000000000002 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fdbeb1e6128 R14: 00007fdbeb1e6090 R15: 00007fdbeb30fa28 INFO: task syz.2.2197:14487 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.2197 state:D stack:26920 pid:14487 tgid:14476 ppid:5846 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 io_schedule+0x80/0xd0 kernel/sched/core.c:7871 folio_wait_bit_common+0x6b0/0xb80 mm/filemap.c:1330 __folio_lock mm/filemap.c:1706 [inline] folio_lock include/linux/pagemap.h:1141 [inline] __filemap_get_folio+0x139/0xaf0 mm/filemap.c:1960 filemap_lock_folio include/linux/pagemap.h:820 [inline] filemap_lock_hugetlb_folio include/linux/hugetlb.h:814 [inline] hugetlbfs_zero_partial_page+0xae/0x610 fs/hugetlbfs/inode.c:654 hugetlbfs_punch_hole fs/hugetlbfs/inode.c:695 [inline] hugetlbfs_fallocate+0x4e4/0x1100 fs/hugetlbfs/inode.c:741 vfs_fallocate+0x669/0x7e0 fs/open.c:342 madvise_remove mm/madvise.c:1049 [inline] madvise_vma_behavior+0x31b3/0x3a10 mm/madvise.c:1346 madvise_walk_vmas+0x51c/0xa30 mm/madvise.c:1669 madvise_do_behavior+0x38e/0x550 mm/madvise.c:1885 do_madvise+0x1bc/0x270 mm/madvise.c:1978 __do_sys_madvise mm/madvise.c:1987 [inline] __se_sys_madvise mm/madvise.c:1985 [inline] __x64_sys_madvise+0xa7/0xc0 mm/madvise.c:1985 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdbeaf8eec9 RSP: 002b:00007fdbebe97038 EFLAGS: 00000246 ORIG_RAX: 000000000000001c RAX: ffffffffffffffda RBX: 00007fdbeb1e6270 RCX: 00007fdbeaf8eec9 RDX: 0000000000000009 RSI: 0000000000002000 RDI: 000020000032d000 RBP: 00007fdbeb011f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fdbeb1e6308 R14: 00007fdbeb1e6270 R15: 00007fdbeb30fa28 Showing all locks held in the system: 2 locks held by ksoftirqd/1/23: 1 lock held by khungtaskd/31: #0: ffffffff8e13d320 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13d320 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e13d320 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5593: #0: ffff88803334a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by kworker/u9:1/12355: #0: ffff88805f890948 ((wq_completion)hci0){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88805f890948 ((wq_completion)hci0){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc9001b9efba0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc9001b9efba0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff888054bccdc8 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d4/0x3a0 net/bluetooth/hci_sync.c:331 1 lock held by syz.2.2197/14480: #0: ffff888053b11318 (&hugetlbfs_i_mmap_rwsem_key){++++}-{4:4}, at: i_mmap_lock_read include/linux/fs.h:568 [inline] #0: ffff888053b11318 (&hugetlbfs_i_mmap_rwsem_key){++++}-{4:4}, at: __rmap_walk_file+0x227/0x620 mm/rmap.c:2905 3 locks held by syz.2.2197/14487: #0: ffff8880216ca420 (sb_writers#12){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3111 [inline] #0: ffff8880216ca420 (sb_writers#12){.+.+}-{0:0}, at: vfs_fallocate+0x5f0/0x7e0 fs/open.c:341 #1: ffff888053b11048 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline] #1: ffff888053b11048 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: hugetlbfs_punch_hole fs/hugetlbfs/inode.c:683 [inline] #1: ffff888053b11048 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: hugetlbfs_fallocate+0x3cc/0x1100 fs/hugetlbfs/inode.c:741 #2: ffff888053b11318 (&hugetlbfs_i_mmap_rwsem_key){++++}-{4:4}, at: i_mmap_lock_write include/linux/fs.h:548 [inline] #2: ffff888053b11318 (&hugetlbfs_i_mmap_rwsem_key){++++}-{4:4}, at: hugetlbfs_punch_hole fs/hugetlbfs/inode.c:691 [inline] #2: ffff888053b11318 (&hugetlbfs_i_mmap_rwsem_key){++++}-{4:4}, at: hugetlbfs_fallocate+0x4b5/0x1100 fs/hugetlbfs/inode.c:741 3 locks held by syz.4.2727/16966: 2 locks held by syz.6.2735/16995: #0: ffffffff8f9e5108 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8f9e5108 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8f9e5108 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8e142c80 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3820 2 locks held by syz.7.2738/17008: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 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:332 [inline] watchdog+0xf60/0xfa0 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 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: 5836 Comm: kworker/u9:6 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: hci0 hci_cmd_timeout RIP: 0010:io_serial_out+0x7c/0xc0 drivers/tty/serial/8250/8250_port.c:407 Code: 68 a4 fc 44 89 f9 d3 e5 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 7c 06 0a fd 41 03 2e 89 d8 89 ea ee <5b> 41 5c 41 5e 41 5f 5d e9 87 f8 32 06 cc 44 89 f9 80 e1 07 38 c1 RSP: 0018:ffffc9000422f2f0 EFLAGS: 00000002 RAX: 0000000000000030 RBX: 0000000000000030 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000020 RBP: 00000000000003f8 R08: ffff888024370237 R09: 1ffff1100486e046 R10: dffffc0000000000 R11: ffffffff851b2b90 R12: dffffc0000000000 R13: ffffffff99a028e5 R14: ffffffff99d15fe0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888125e12000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555572f115c8 CR3: 0000000023e08000 CR4: 00000000003526f0 Call Trace: serial_port_out include/linux/serial_core.h:811 [inline] serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3192 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:-1 [inline] serial8250_console_write+0x1410/0x1ba0 drivers/tty/serial/8250/8250_port.c:3342 console_emit_next_record kernel/printk/printk.c:3111 [inline] console_flush_all+0x6f0/0xb10 kernel/printk/printk.c:3199 __console_flush_and_unlock kernel/printk/printk.c:3258 [inline] console_unlock+0xbb/0x190 kernel/printk/printk.c:3298 vprintk_emit+0x4c5/0x590 kernel/printk/printk.c:2423 _printk+0xcf/0x120 kernel/printk/printk.c:2448 bt_err+0x10b/0x160 net/bluetooth/lib.c:296 hci_cmd_timeout+0xd8/0x1e0 net/bluetooth/hci_core.c:1469 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245