rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=2d6c/1/0x4000000000000000 softirq=25672/25672 fqs=0
rcu: 	(detected by 1, t=10506 jiffies, g=15001, q=734 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6507 Comm: syz.1.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__sanitizer_cov_trace_pc+0x66/0x70 kernel/kcov.c:235
Code: 82 18 16 00 00 83 f8 02 75 20 48 8b 8a 20 16 00 00 8b 92 1c 16 00 00 48 8b 01 48 83 c0 01 48 39 d0 73 07 48 89 01 48 89 34 c1 <e9> 85 24 db 09 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000007e38 EFLAGS: 00000046
RAX: 0000000000010000 RBX: ffff8880b8427d80 RCX: ffffffff81a85b15
RDX: ffff88802c8b0000 RSI: ffffffff81a85b24 RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000007
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880b8427c80
R13: 0000000000000000 R14: ffff88807aa35340 R15: 0000000000000001
FS:  00007f09591e16c0(0000) GS:ffff8881246bc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f09591bff98 CR3: 0000000055b05000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 cpumask_test_cpu include/linux/cpumask.h:646 [inline]
 cpu_online include/linux/cpumask.h:1205 [inline]
 trace_hrtimer_expire_exit include/trace/events/timer.h:306 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1764 [inline]
 __hrtimer_run_queues+0x274/0xad0 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x3f0 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lockdep_unregister_key+0xe9/0x140 kernel/locking/lockdep.c:6616
Code: 48 89 ef e8 b9 e5 ff ff 48 83 2d c9 a3 5e 14 01 89 c3 e8 da ee ff ff 9c 58 f6 c4 02 75 52 41 f7 c4 00 02 00 00 74 01 fb 84 db <75> 1b 5b 5d 41 5c e9 4c 76 0a 00 8b 05 8a 0f 14 0f 31 db 85 c0 74
RSP: 0018:ffffc90003cdf318 EFLAGS: 00000246
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8df43339 RDI: ffffffff8c162900
RBP: ffffffff975b0a38 R08: 0000000000003eca R09: ffffffff95f68774
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000246
R13: ffff888028210000 R14: ffff88807aa35000 R15: ffff888028210000
 __qdisc_destroy+0x11a/0x4d0 net/sched/sch_generic.c:1083
 qdisc_put+0xab/0xe0 net/sched/sch_generic.c:1109
 taprio_attach+0x1fc/0x370 net/sched/sch_taprio.c:2160
 qdisc_graft+0xe3f/0x17c0 net/sched/sch_api.c:1162
 __tc_modify_qdisc net/sched/sch_api.c:1756 [inline]
 tc_modify_qdisc+0xf5c/0x2170 net/sched/sch_api.c:1812
 rtnetlink_rcv_msg+0x3c6/0xe90 net/core/rtnetlink.c:6955
 netlink_rcv_skb+0x155/0x420 net/netlink/af_netlink.c:2552
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg net/socket.c:729 [inline]
 ____sys_sendmsg+0xa98/0xc70 net/socket.c:2614
 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2668
 __sys_sendmsg+0x16d/0x220 net/socket.c:2700
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f095838e969
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:00007f09591e1038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f09585b5fa0 RCX: 00007f095838e969
RDX: 0000000000000000 RSI: 00002000000007c0 RDI: 0000000000000005
RBP: 00007f0958410ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f09585b5fa0 R15: 00007ffdc4eb2188
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g15001 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=7571
rcu: rcu_preempt kthread starved for 10506 jiffies! g15001 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
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:I stack:27784 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:7058
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2285
 kthread+0x3c2/0x780 kernel/kthread.c:463
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>