syzbot

INFO: task syz-executor412:5144 blocked for more than 143 seconds.
      Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor412 state:D stack:26256 pid:5144  tgid:5143  ppid:5095   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5409 [inline]
 __schedule+0x1781/0x49d0 kernel/sched/core.c:6736
 __schedule_loop kernel/sched/core.c:6813 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6828
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6885
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752
 bdev_release+0x1cb/0xa20 block/bdev.c:1028
 blkdev_release+0x15/0x20 block/fops.c:628
 __fput+0x429/0x8a0 fs/file_table.c:422
 task_work_run+0x24f/0x310 kernel/task_work.c:180
 get_signal+0x1673/0x1850 kernel/signal.c:2683
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:105 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline]
 syscall_exit_to_user_mode+0xc9/0x360 kernel/entry/common.c:212
 do_syscall_64+0x10a/0x240 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7f1b8cc38479
RSP: 002b:00007f1b8cbf0228 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007f1b8ccbf328 RCX: 00007f1b8cc38479
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
RBP: 00007f1b8ccbf320 R08: 00007f1b8cbf06c0 R09: 00007f1b8cbf06c0
R10: 00007f1b8cbf06c0 R11: 0000000000000246 R12: 00007f1b8ccbf32c
R13: 00007f1b8cc8c1a4 R14: 64626e2f7665642f R15: 00007ffe6d825f78
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/29:
 #0: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
 #0: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
 #0: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614
2 locks held by getty/4817:
 #0: ffff88802a9d40a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90002f0e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2201
1 lock held by udevd/5096:
 #0: ffff8880201a04c8 (&disk->open_mutex){+.+.}-{3:3}, at: bdev_open+0xdc/0xc90 block/bdev.c:862
1 lock held by syz-executor412/5144:
 #0: ffff8880201a04c8 (&disk->open_mutex){+.+.}-{3:3}, at: bdev_release+0x1cb/0xa20 block/bdev.c:1028

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

NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xfb0/0xff0 kernel/hung_task.c:379
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 11 Comm: kworker/u8:1 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:__lock_acquire+0x97/0x1fd0
Code: 00 74 12 4c 89 e7 e8 e8 55 83 00 48 be 00 00 00 00 00 fc ff df 48 c7 c0 00 e4 b6 92 49 39 04 24 75 08 c7 44 24 38 00 00 00 00 <89> 5c 24 48 83 fd 01 77 2e 89 e8 49 8d 5c c4 08 48 89 d8 48 c1 e8
RSP: 0018:ffffc90000107330 EFLAGS: 00000006
RAX: ffffffff92b6e400 RBX: 0000000000000000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: dffffc0000000000 RDI: ffffffff8e132020
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f0c1be R12: ffffffff8e132020
R13: 0000000000000000 R14: ffff88801729bc00 R15: 0000000000000002
FS:  0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055a674ffdff8 CR3: 000000000df32000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754
 rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
 rcu_read_lock include/linux/rcupdate.h:750 [inline]
 __pte_offset_map+0x9e/0x380 mm/pgtable-generic.c:285
 __pte_offset_map_lock+0xc7/0x300 mm/pgtable-generic.c:369
 get_locked_pte include/linux/mm.h:2683 [inline]
 __text_poke+0x2c5/0xd30 arch/x86/kernel/alternative.c:1900
 text_poke arch/x86/kernel/alternative.c:1985 [inline]
 text_poke_bp_batch+0x8cd/0xb30 arch/x86/kernel/alternative.c:2374
 text_poke_flush arch/x86/kernel/alternative.c:2487 [inline]
 text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2494
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:205
 static_key_enable+0x1a/0x20 kernel/jump_label.c:218
 toggle_allocation_gate+0xb5/0x250 mm/kfence/core.c:826
 process_one_work kernel/workqueue.c:3254 [inline]
 process_scheduled_works+0xa00/0x1770 kernel/workqueue.c:3335
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.807 msecs