syzbot

INFO: task syz-executor634:4271 blocked for more than 143 seconds.
      Not tainted 6.1.127-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor634 state:D stack:23880 pid:4271  ppid:4269   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 io_schedule+0x88/0x100 kernel/sched/core.c:8786
 folio_wait_bit_common+0x878/0x1290 mm/filemap.c:1324
 truncate_inode_pages_range+0xbb5/0x1340 mm/truncate.c:422
 evict+0x53c/0x930 fs/inode.c:707
 dispose_list fs/inode.c:738 [inline]
 evict_inodes+0x668/0x700 fs/inode.c:792
 generic_shutdown_super+0x94/0x340 fs/super.c:480
 kill_block_super+0x7a/0xe0 fs/super.c:1470
 deactivate_locked_super+0xa0/0x110 fs/super.c:332
 cleanup_mnt+0x490/0x520 fs/namespace.c:1186
 task_work_run+0x246/0x300 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe99532a407
RSP: 002b:00007ffcf55844f8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fe99532a407
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffcf55845b0
RBP: 00007ffcf55845b0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000202 R12: 00007ffcf5585610
R13: 0000555577b446c0 R14: 0000000000000001 R15: 431bde82d7b634db
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8d32b290 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8d32ba90 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
 #0: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510
2 locks held by getty/4019:
 #0: ffff8880311a6098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc9000325e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2198
1 lock held by syz-executor634/4271:
 #0: ffff8880310220e0 (&type->s_umount_key#42){+.+.}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:362

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

NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.1.127-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1ae/0x3f0 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+0xf88/0xfd0 kernel/hung_task.c:377
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 11 Comm: kworker/u4:1 Not tainted 6.1.127-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:__mutex_lock+0x95/0xd80 kernel/locking/mutex.c:746
Code: 00 c0 e3 bb 8a 48 8d 84 24 80 00 00 00 48 c1 e8 03 42 c7 04 20 f1 f1 f1 f1 42 c7 44 20 09 f3 f3 f3 f3 66 42 c7 44 20 0d f3 f3 <48> 89 44 24 28 42 c6 44 20 0f f3 ba 28 00 00 00 31 f6 e8 d4 4c 26
RSP: 0018:ffffc900001079a0 EFLAGS: 00000a06
RAX: 1ffff92000020f44 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffffc90000107a40
RBP: ffffc90000107af0 R08: ffffffff8131107e R09: fffff52000020f41
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffffffff8d1dd380 R14: 0000000000000000 R15: ffffffff973bcf20
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055f1fedcb600 CR3: 000000000d08e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 arch_jump_label_transform_apply+0xe/0x20 arch/x86/kernel/jump_label.c:145
 static_key_disable_cpuslocked+0xce/0x1b0 kernel/jump_label.c:237
 static_key_disable+0x16/0x20 kernel/jump_label.c:245
 toggle_allocation_gate+0x3e0/0x480 mm/kfence/core.c:818
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>