rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=edcc/1/0x4000000000000000 softirq=21859/21859 fqs=2
rcu: 	(detected by 1, t=10502 jiffies, g=16269, q=768 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6486 Comm: syz.3.20 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:div64_u64 include/linux/math64.h:69 [inline]
RIP: 0010:taprio_set_budgets+0x223/0x3b0 net/sched/sch_taprio.c:674
Code: 89 f7 e8 10 c3 c5 f8 49 8b 0e 4c 89 e8 48 09 c8 48 c1 e8 20 74 0d 4c 89 e8 31 d2 48 f7 f1 49 89 c5 eb 0a 44 89 e8 31 d2 f7 f1 <41> 89 c5 bf 11 00 00 00 4c 89 e6 e8 9d 12 60 f8 49 83 fc 10 77 6c
RSP: 0018:ffffc90000007c00 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000190
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff8880780eb260
RBP: 0000000000000000 R08: ffff8880780eb267 R09: 1ffff1100f01d64c
R10: dffffc0000000000 R11: ffffed100f01d64d R12: 0000000000000000
R13: 0000000000000000 R14: ffff8880780eb260 R15: ffff888059d4f400
FS:  00007fb0af2ca6c0(0000) GS:ffff888126140000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc958d9058 CR3: 0000000071e2a000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 advance_sched+0x963/0xc90 net/sched/sch_taprio.c:982
 __run_hrtimer kernel/time/hrtimer.c:1777 [inline]
 __hrtimer_run_queues+0x52c/0xc60 kernel/time/hrtimer.c:1841
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1058
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1052
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lockdep_unregister_key+0x2c5/0x310 kernel/locking/lockdep.c:6616
Code: 65 48 8b 05 ed 88 d0 10 48 3b 44 24 10 0f 84 26 fe ff ff e8 9d 79 a8 09 e8 c8 7a a8 09 41 f7 c7 00 02 00 00 74 bd fb 40 84 ed <75> bc eb cd 90 0f 0b 90 e9 19 ff ff ff 90 0f 0b 90 e9 2a ff ff ff
RSP: 0018:ffffc90003eaf088 EFLAGS: 00000246
RAX: 8c4964f5a4676600 RBX: ffff88807909d228 RCX: 8c4964f5a4676600
RDX: ffffffff9331b358 RSI: ffffffff8d71fee4 RDI: ffffffff8bbf0460
RBP: ffff88807909d200 R08: 0000000000000000 R09: ffffffff81aa7378
R10: dffffc0000000000 R11: fffffbfff1ef996f R12: 0000000000000000
R13: 0000000000001000 R14: 0000000000000001 R15: 0000000000000202
 __qdisc_destroy+0x166/0x420 net/sched/sch_generic.c:1076
 taprio_attach+0x25a/0x380 net/sched/sch_taprio.c:2160
 qdisc_graft+0x1175/0x1590 net/sched/sch_api.c:1162
 __tc_modify_qdisc net/sched/sch_api.c:1756 [inline]
 tc_modify_qdisc+0x189b/0x20e0 net/sched/sch_api.c:1812
 rtnetlink_rcv_msg+0x77c/0xb70 net/core/rtnetlink.c:6960
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2550
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:742
 ____sys_sendmsg+0x505/0x830 net/socket.c:2630
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2684
 __sys_sendmsg net/socket.c:2716 [inline]
 __do_sys_sendmsg net/socket.c:2721 [inline]
 __se_sys_sendmsg net/socket.c:2719 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2719
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb0ae38eec9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007fb0af2ca038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fb0ae5e5fa0 RCX: 00007fb0ae38eec9
RDX: 0000000000000000 RSI: 00002000000007c0 RDI: 0000000000000004
RBP: 00007fb0ae411f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb0ae5e6038 R14: 00007fb0ae5e5fa0 R15: 00007ffe0332f078
 </TASK>
rcu: rcu_preempt kthread starved for 10498 jiffies! g16269 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27224 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7026
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 79 Comm: kworker/u8:4 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xd33/0x12d0 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 b6 73 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 6f 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 45 6f
RSP: 0018:ffffc9000218f640 EFLAGS: 00000293
RAX: ffffffff81b494ab RBX: 1ffff11017108441 RCX: ffff88801c745ac0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000218f7c0 R08: ffffffff8f7ccb77 R09: 1ffffffff1ef996e
R10: dffffc0000000000 R11: fffffbfff1ef996f R12: ffff8880b8842208
R13: dffffc0000000000 R14: ffff8880b893b200 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888126240000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc958d9058 CR3: 000000000dd38000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
 on_each_cpu include/linux/smp.h:71 [inline]
 smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2713 [inline]
 smp_text_poke_batch_finish+0x5f9/0x1130 arch/x86/kernel/alternative.c:2923
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210
 static_key_enable+0x1a/0x20 kernel/jump_label.c:223
 toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:852
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>