syzbot

INFO: task syz-executor423:4277 blocked for more than 143 seconds.
      Not tainted 6.1.129-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor423 state:D stack:26816 pid:4277  ppid:4265   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5243 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6560
 schedule+0xbf/0x180 kernel/sched/core.c:6636
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6695
 rwsem_down_read_slowpath kernel/locking/rwsem.c:1094 [inline]
 __down_read_common kernel/locking/rwsem.c:1261 [inline]
 __down_read kernel/locking/rwsem.c:1274 [inline]
 down_read+0x6ff/0xa30 kernel/locking/rwsem.c:1522
 iterate_supers+0xac/0x1e0 fs/super.c:755
 quota_sync_all fs/quota/quota.c:69 [inline]
 __do_sys_quotactl fs/quota/quota.c:937 [inline]
 __se_sys_quotactl+0x347/0x770 fs/quota/quota.c:916
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fdf4f01e899
RSP: 002b:00007fdf4efd7158 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007fdf4f0a6428 RCX: 00007fdf4f01e899
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000102
RBP: 00007fdf4f0a6420 R08: 00007fdf4efd76c0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fdf4f0a642c
R13: 0000000000000006 R14: 00007ffc2ca4a9f0 R15: 00007ffc2ca4aad8
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8d32e850 (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: ffffffff8d32f050 (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: ffffffff8d32e680 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8d32e680 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8d32e680 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510
1 lock held by klogd/3612:
 #0: ffff8880b8e3a9d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537
2 locks held by getty/4004:
 #0: ffff88814d187098 (&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+0x54a/0x1620 drivers/tty/n_tty.c:2198
1 lock held by syz-executor423/4277:
 #0: ffff88807754a0e0 (&type->s_umount_key#67){.+.+}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:755
1 lock held by syz-executor423/4278:
 #0: ffff88807754a0e0 (&type->s_umount_key#66/1){+.+.}-{3:3}, at: alloc_super+0x217/0x930 fs/super.c:228

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

NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.1.129-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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+0x1ca/0x430 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: 4279 Comm: kworker/u4:1 Not tainted 6.1.129-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:__might_resched+0x18d/0x780 kernel/sched/core.c:9921
Code: 41 8b 45 00 c1 e0 08 01 d8 44 39 e0 0f 85 d6 00 00 00 44 89 64 24 1c 48 8d bc 24 a0 00 00 00 48 89 fb 48 c1 eb 03 80 3c 13 00 <74> 31 48 8d bc 24 a0 00 00 00 45 89 f4 4d 89 ee 49 89 f5 e8 9b 9e
RSP: 0018:ffffc90003e57800 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 1ffff920007caf14 RCX: ffff88802df38000
RDX: dffffc0000000000 RSI: ffff88802df38000 RDI: ffffc90003e578a0
RBP: ffffc90003e57910 R08: dffffc0000000000 R09: ffffc90003e579c0
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff88802df3843c R14: 0000000000000244 R15: 1ffff920007caf08
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000558e9f7cf938 CR3: 000000000d08e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 __mutex_lock_common kernel/locking/mutex.c:580 [inline]
 __mutex_lock+0xbd/0xd80 kernel/locking/mutex.c:747
 arch_jump_label_transform_queue+0x40/0xd0 arch/x86/kernel/jump_label.c:136
 __jump_label_update+0x177/0x3a0 kernel/jump_label.c:510
 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:819
 process_one_work+0x917/0x1260 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>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.063 msecs