INFO: task syz.0.251:4688 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.251       state:D stack:27632 pid:4688  ppid:4390   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5246 [inline]
 __schedule+0x107f/0x4030 kernel/sched/core.c:6563
 schedule+0xb9/0x180 kernel/sched/core.c:6639
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799
 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209
 __wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49
 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64
 wait_on_bit_io include/linux/wait_bit.h:101 [inline]
 do_get_write_access+0x605/0xf20 fs/jbd2/transaction.c:1115
 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250
 __ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235
 ext4_reserve_inode_write+0x201/0x290 fs/ext4/inode.c:5945
 __ext4_mark_inode_dirty+0x161/0x760 fs/ext4/inode.c:6119
 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6156
 __mark_inode_dirty+0x2e7/0xe80 fs/fs-writeback.c:2500
 generic_update_time fs/inode.c:1946 [inline]
 inode_update_time fs/inode.c:1959 [inline]
 __file_update_time+0x21d/0x240 fs/inode.c:2147
 file_update_time+0x2f3/0x370 fs/inode.c:2178
 ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6274
 do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009
 do_shared_fault mm/memory.c:4694 [inline]
 do_fault mm/memory.c:4762 [inline]
 handle_pte_fault mm/memory.c:5029 [inline]
 __handle_mm_fault mm/memory.c:5171 [inline]
 handle_mm_fault+0x199c/0x3d40 mm/memory.c:5292
 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338
 handle_page_fault arch/x86/mm/fault.c:1429 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7f62e946ba23
RSP: 002b:00007ffc178c6140 EFLAGS: 00010246
RAX: 000000000003fde8 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000001b2f124000 RSI: 0000000000040000 RDI: 00007f62e97e0708
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffc178c63d0
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8cb2e4f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8cb2ed10 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
 #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6527
7 locks held by kworker/u4:3/47:
 #0: ffff888141689138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
 #1: ffffc90000b87d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
 #2: ffff88814d3800e0 (&type->s_umount_key#32){++++}-{3:3}, at: trylock_super+0x1c/0xf0 fs/super.c:415
 #3: ffff88814d382c18 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x213/0x2e70 fs/ext4/inode.c:2717
 #4: ffff88814d384990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463
 #5: ffff888074ad8288 (&ei->i_data_sem){++++}-{3:3}, at: ext4_map_blocks+0x914/0x1a90 fs/ext4/inode.c:674
 #6: ffffe8ffffd33e68 (&lg->lg_mutex){+.+.}-{3:3}, at: ext4_mb_group_or_file fs/ext4/mballoc.c:5306 [inline]
 #6: ffffe8ffffd33e68 (&lg->lg_mutex){+.+.}-{3:3}, at: ext4_mb_initialize_context+0x7f0/0xb80 fs/ext4/mballoc.c:5349
2 locks held by getty/4032:
 #0: ffff88814d05b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41e/0x1360 drivers/tty/n_tty.c:2198
3 locks held by syz.0.251/4688:
 #0: ffff88803022f1d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88803022f1d8 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline]
 #0: ffff88803022f1d8 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382
 #1: ffff88814d380558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1891 [inline]
 #1: ffff88814d380558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1995 [inline]
 #1: ffff88814d380558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6273
 #2: ffff88814d384990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463
2 locks held by syz-executor/4694:
 #0: ffff88814d380460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:402
 #1: ffff88807498ca38 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline]
 #1: ffff88807498ca38 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: filename_create+0x20b/0x450 fs/namei.c:3884

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

NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xf0e/0xf50 kernel/hung_task.c:377
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 1127 Comm: kworker/u4:4 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:insn_get_length arch/x86/lib/insn.c:707 [inline]
RIP: 0010:insn_decode+0x37e/0x520 arch/x86/lib/insn.c:747
Code: 0f b6 03 0f b6 d8 31 ff 89 de e8 5d e6 5d f7 84 db 74 4f e8 f4 e3 5d f7 31 c0 eb 50 e8 eb e3 5d f7 eb 44 e8 e4 e3 5d f7 eb 3d <48> 89 df e8 1a dc ff ff 89 c5 31 ff 89 c6 e8 2f e7 5d f7 85 ed 74
RSP: 0018:ffffc90004f0f8e8 EFLAGS: 00000246
RAX: ffffffff8a2448f6 RBX: ffffc90004f0f960 RCX: 0000000000000000
RDX: ffff888026ef1e00 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffc90004f0f9b7 R09: ffffc90004f0f960
R10: dffffc0000000000 R11: fffff520009e1f37 R12: dffffc0000000000
R13: 1ffff920009e1f36 R14: ffffc90004f0f9b2 R15: ffffc90004f0f99c
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055a2452da168 CR3: 000000000c88e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 arch_jump_entry_size arch/x86/kernel/jump_label.c:24 [inline]
 __jump_label_patch+0x105/0x450 arch/x86/kernel/jump_label.c:45
 arch_jump_label_transform_queue+0x48/0xd0 arch/x86/kernel/jump_label.c:137
 __jump_label_update+0x18a/0x3c0 kernel/jump_label.c:510
 static_key_disable_cpuslocked+0xc1/0x1a0 kernel/jump_label.c:237
 static_key_disable+0x16/0x20 kernel/jump_label.c:245
 toggle_allocation_gate+0x3d1/0x470 mm/kfence/core.c:835
 process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>