INFO: task syz.4.866:12320 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.866       state:D stack:25080 pid:12320 tgid:12319 ppid:5812   task_flags:0x400140 flags:0x00080003
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1480/0x50a0 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6960
 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
 do_wait_for_common kernel/sched/completion.c:100 [inline]
 __wait_for_common kernel/sched/completion.c:121 [inline]
 wait_for_common kernel/sched/completion.c:132 [inline]
 wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153
 kthread_flush_worker+0x10e/0x160 kernel/kthread.c:1559
 __alloc_workqueue+0x1485/0x1b80 kernel/workqueue.c:5797
 alloc_workqueue_noprof+0xd4/0x210 kernel/workqueue.c:5820
 btrfs_alloc_workqueue+0x1ec/0x2d0 fs/btrfs/async-thread.c:112
 btrfs_init_workqueues+0x348/0x680 fs/btrfs/disk-io.c:1986
 open_ctree+0x141d/0x3d20 fs/btrfs/disk-io.c:3410
 btrfs_fill_super fs/btrfs/super.c:983 [inline]
 btrfs_get_tree_super fs/btrfs/super.c:1946 [inline]
 btrfs_get_tree_subvol fs/btrfs/super.c:2089 [inline]
 btrfs_get_tree+0x1061/0x1920 fs/btrfs/super.c:2123
 vfs_get_tree+0x92/0x2a0 fs/super.c:1751
 fc_mount fs/namespace.c:1199 [inline]
 do_new_mount_fc fs/namespace.c:3636 [inline]
 do_new_mount+0x302/0xa10 fs/namespace.c:3712
 do_mount fs/namespace.c:4035 [inline]
 __do_sys_mount fs/namespace.c:4224 [inline]
 __se_sys_mount+0x313/0x410 fs/namespace.c:4201
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f20a2080eea
RSP: 002b:00007f20a02dde68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f20a02ddef0 RCX: 00007f20a2080eea
RDX: 00002000000055c0 RSI: 0000200000000000 RDI: 00007f20a02ddeb0
RBP: 00002000000055c0 R08: 00007f20a02ddef0 R09: 000000000300000a
R10: 000000000300000a R11: 0000000000000246 R12: 0000200000000000
R13: 00007f20a02ddeb0 R14: 00000000000055a3 R15: 0000200000000080
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/38:
 #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
 #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by udevd/5170:
 #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
 #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: __d_lookup+0x66/0x780 fs/dcache.c:2435
 #1: ffff888031907ad8 (&lockref->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
 #1: ffff888031907ad8 (&lockref->lock){+.+.}-{3:3}, at: __d_lookup+0x23e/0x780 fs/dcache.c:2442
2 locks held by getty/5562:
 #0: ffff88814ee5c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90003e7e2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x44f/0x1460 drivers/tty/n_tty.c:2211
2 locks held by udevd/5945:
 #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
 #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: __d_lookup+0x66/0x780 fs/dcache.c:2435
 #1: ffff888031907ad8 (&lockref->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
 #1: ffff888031907ad8 (&lockref->lock){+.+.}-{3:3}, at: __d_lookup+0x23e/0x780 fs/dcache.c:2442
1 lock held by udevd/9735:
1 lock held by syz.4.866/12320:
 #0: ffff88805f5bc0d0 (&type->s_umount_key#51/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xab0 fs/super.c:344
9 locks held by syz-executor/12506:
2 locks held by kworker/u8:23/13786:
2 locks held by udevadm/14076:
4 locks held by syz.2.1064/14081:
1 lock held by syz.3.1062/14084:
2 locks held by syz.0.1065/14086:
2 locks held by syz.1.1066/14088:
 #0: ffff88803b404480 (sb_writers#13){++++}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1160
 #1: ffff88803d24c128 (&sb->s_type->i_mutex_key#24){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
 #1: ffff88803d24c128 (&sb->s_type->i_mutex_key#24){+.+.}-{4:4}, at: ntfs_file_write_iter+0xe6/0x870 fs/ntfs3/file.c:1284
4 locks held by syz.1.1066/14089:
 #0: ffff88803b404480 (sb_writers#13){++++}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499
 #1: ffff88803d24c128 (&sb->s_type->i_mutex_key#24){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:1032 [inline]
 #1: ffff88803d24c128 (&sb->s_type->i_mutex_key#24){+.+.}-{4:4}, at: do_truncate+0x171/0x220 fs/open.c:63
 #2: ffff88803d24be70 (&ni->ni_lock#3){+.+.}-{4:4}, at: ni_trylock fs/ntfs3/ntfs_fs.h:1147 [inline]
 #2: ffff88803d24be70 (&ni->ni_lock#3){+.+.}-{4:4}, at: ni_write_inode+0x1f1/0xff0 fs/ntfs3/frecord.c:3155
 #3: ffff88805ec24dd0 (&ni->ni_lock#3){+.+.}-{4:4}, at: ni_trylock fs/ntfs3/ntfs_fs.h:1147 [inline]
 #3: ffff88805ec24dd0 (&ni->ni_lock#3){+.+.}-{4:4}, at: ni_update_parent+0x9a9/0xdd0 fs/ntfs3/frecord.c:3116
2 locks held by syz.1.1066/14090:

=============================================

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 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]
 __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+0xf95/0xfe0 kernel/hung_task.c:515
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 14090 Comm: syz.1.1066 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:146 [inline]
RIP: 0010:lock_acquire+0x159/0x340 kernel/locking/lockdep.c:5869
Code: 05 7c cf 14 10 83 f8 01 0f 85 c9 00 00 00 48 c7 44 24 30 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 <f7> 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 b4 88 14 10 48 3b 44
RSP: 0018:ffffc9000497ef80 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: b83c92270a5bb700
RDX: 000000002b3bebc4 RSI: ffffffff8cfdf958 RDI: ffffffff8b3f4de0
RBP: ffffffff81aac92d R08: ffffffff81aac92d R09: ffffffff8d5ae880
R10: ffffc9000497f0f8 R11: ffffffff81ac51a0 R12: 0000000000000002
R13: ffffffff8d5ae880 R14: 0000000000000000 R15: 0000000000000246
FS:  00007f13b10846c0(0000) GS:ffff888126e06000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8dcc26a000 CR3: 000000005a76c000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:867 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
 is_module_text_address+0x39/0x1e0 kernel/module/main.c:3856
 kernel_text_address+0x94/0xe0 kernel/extable.c:119
 __kernel_text_address+0xd/0x40 kernel/extable.c:79
 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369
 arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 save_stack+0xf7/0x1f0 mm/page_owner.c:165
 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 free_unref_folios+0xc28/0x1810 mm/page_alloc.c:3000
 folios_put_refs+0x569/0x670 mm/swap.c:1002
 free_pages_and_swap_cache+0x4be/0x520 mm/swap_state.c:358
 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
 tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:397 [inline]
 tlb_flush_mmu+0x3a0/0x680 mm/mmu_gather.c:404
 tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497
 vms_clear_ptes+0x42b/0x530 mm/vma.c:1238
 vms_complete_munmap_vmas+0x206/0x8a0 mm/vma.c:1280
 do_vmi_align_munmap+0x372/0x450 mm/vma.c:1539
 do_vmi_munmap+0x253/0x2e0 mm/vma.c:1587
 __vm_munmap+0x207/0x380 mm/vma.c:3203
 __do_sys_munmap mm/mmap.c:1077 [inline]
 __se_sys_munmap mm/mmap.c:1074 [inline]
 __x64_sys_munmap+0x60/0x70 mm/mmap.c:1074
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f13b2e5f7d7
Code: 00 00 00 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 0b 00 00 00 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:00007f13b1083e18 EFLAGS: 00000246 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 0000000000200000 RCX: 00007f13b2e5f7d7
RDX: 0000000000000000 RSI: 0000000008400000 RDI: 00007f13a8c64000
RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000001f1eb
R10: 0000000000003ffc R11: 0000000000000246 R12: 0000000000000008
R13: 00007f13b1083ef0 R14: 00007f13b1083eb0 R15: 00007f13a8c64000
 </TASK>