INFO: task syz-executor:5827 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:22592 pid:5827 tgid:5827 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5340 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 io_schedule+0x7f/0xd0 kernel/sched/core.c:7831 folio_wait_bit_common+0x6d8/0xbc0 mm/filemap.c:1323 __folio_lock mm/filemap.c:1699 [inline] folio_lock include/linux/pagemap.h:1170 [inline] __filemap_get_folio_mpol+0x13e/0xb00 mm/filemap.c:1954 __filemap_get_folio include/linux/pagemap.h:774 [inline] truncate_inode_pages_range+0x48b/0xe30 mm/truncate.c:413 evict+0x631/0xb10 fs/inode.c:848 dispose_list fs/inode.c:888 [inline] evict_inodes+0x75a/0x7f0 fs/inode.c:942 generic_shutdown_super+0xaa/0x2d0 fs/super.c:632 kill_block_super+0x44/0x90 fs/super.c:1725 deactivate_locked_super+0xbc/0x130 fs/super.c:476 cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f72ac99d9d7 RSP: 002b:00007fffb850dea8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f72aca31f90 RCX: 00007f72ac99d9d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fffb850df60 RBP: 00007fffb850df60 R08: 00007fffb850ef60 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007fffb850eff0 R13: 00007f72aca31f90 R14: 000000000003982a R15: 00007fffb850f030 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/u8:14/3525: #0: ffff88813fe44948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline] #0: ffff88813fe44948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358 #1: ffffc9000ce3fc40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #1: ffffc9000ce3fc40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358 2 locks held by getty/5581: #0: ffff8880363db0a0 (&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+0x45c/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by syz-executor/5827: #0: ffff88802a95a0e0 (&type->s_umount_key#81){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88802a95a0e0 (&type->s_umount_key#81){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88802a95a0e0 (&type->s_umount_key#81){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 2 locks held by syz.2.688/8964: #0: ffff8880474287c8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline] #0: ffff8880474287c8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline] #0: ffff8880474287c8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1455 #1: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #1: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961 2 locks held by dhcpcd-run-hook/9054: 1 lock held by modprobe/9056: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xfd9/0x1030 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 8742 Comm: syz.6.640 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:zone_spans_pfn include/linux/mmzone.h:1124 [inline] RIP: 0010:get_pfnblock_bitmap_bitidx mm/page_alloc.c:401 [inline] RIP: 0010:__get_pfnblock_flags_mask+0xb4/0x240 mm/page_alloc.c:428 Code: 01 00 00 49 69 ed 80 07 00 00 4d 8d 2c 2c 49 81 c5 90 00 00 00 4c 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 <74> 08 4c 89 ef e8 82 35 0f 00 49 8b 5d 00 4c 39 f3 0f 87 43 01 00 RSP: 0018:ffffc9000f7c70e0 EFLAGS: 00000246 RAX: 1ffff11027fff782 RBX: ff000fffffffffff RCX: dffffc0000000000 RDX: 0000000000000017 RSI: 00000000000481a5 RDI: ffffea0001206940 RBP: 0000000000000780 R08: dffffc0000000000 R09: ffffed10080e8000 R10: dffffc0000000000 R11: fffffbfff2023197 R12: ffff88813fffb400 R13: ffff88813fffbc10 R14: 00000000000481a5 R15: ffffea0001206940 FS: 0000000000000000(0000) GS:ffff888125463000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd7b4e2f000 CR3: 000000007594c000 CR4: 0000000000350ef0 Call Trace: get_pfnblock_migratetype mm/page_alloc.c:476 [inline] free_unref_folios+0x11c3/0x16d0 mm/page_alloc.c:3066 folios_put_refs+0x789/0x8d0 mm/swap.c:1002 folio_batch_release include/linux/pagevec.h:101 [inline] shmem_undo_range+0x52c/0x1660 mm/shmem.c:1149 shmem_truncate_range mm/shmem.c:1277 [inline] shmem_evict_inode+0x240/0x9e0 mm/shmem.c:1407 evict+0x61e/0xb10 fs/inode.c:846 __dentry_kill+0x1a2/0x5e0 fs/dcache.c:670 finish_dput+0xc9/0x480 fs/dcache.c:879 __fput+0x691/0xa70 fs/file_table.c:477 task_work_run+0x1d9/0x270 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x69b/0x2320 kernel/exit.c:971 do_group_exit+0x21b/0x2d0 kernel/exit.c:1112 get_signal+0x1284/0x1330 kernel/signal.c:3034 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop kernel/entry/common.c:98 [inline] __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline] irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline] irqentry_exit+0x176/0x620 kernel/entry/common.c:219 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f6a98d9c7a1 Code: Unable to access opcode bytes at 0x7f6a98d9c777. RSP: 002b:fffffffffffffe70 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f6a99016270 RCX: 00007f6a98d9c799 RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000 RBP: 00007f6a98e32bd9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f6a99016308 R14: 00007f6a99016270 R15: 00007ffd7bc36f48