rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (1 GPs behind) idle=6304/1/0x4000000000000000 softirq=97093/97094 fqs=5241
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:     6056          0            0
rcu: 	cputime:      129      52349            2   ==> 52480(ms)
rcu: 	(t=10500 jiffies g=64033 q=1502 ncpus=2)
CPU: 1 UID: 0 PID: 15908 Comm: syz.2.2569 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_cmp4+0x2f/0x90 kernel/kcov.c:288
Code: 8b 04 24 65 48 8b 14 25 08 20 80 92 65 8b 0d 98 26 bf 10 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba 6c 16 00 00 00 <74> 52 8b 8a 48 16 00 00 83 f9 03 75 47 48 8b 8a 50 16 00 00 44 8b
RSP: 0018:ffffc90000a08cd0 EFLAGS: 00000246
RAX: ffffffff8970911c RBX: 000000000000000c RCX: 0000000000000100
RDX: ffff888021a99e80 RSI: 000000000000000c RDI: 0000000000000009
RBP: 1ffff1100edbba6a R08: ffffffff896feaf6 R09: ffffffff8df41aa0
R10: 0000000000000001 R11: ffffffff89631470 R12: dffffc0000000000
R13: ffff888076ddd354 R14: 0000000000000009 R15: 0000000000000008
FS:  00007f57452976c0(0000) GS:ffff888125f1e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001000 CR3: 00000000a035c000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 taprio_next_tc_txq net/sched/sch_taprio.c:769 [inline]
 taprio_dequeue_tc_priority+0x20c/0x750 net/sched/sch_taprio.c:796
 taprio_dequeue+0x186/0x550 net/sched/sch_taprio.c:-1
 dequeue_skb net/sched/sch_generic.c:297 [inline]
 qdisc_restart net/sched/sch_generic.c:402 [inline]
 __qdisc_run+0x23f/0x1510 net/sched/sch_generic.c:420
 qdisc_run+0xc7/0x300 include/net/pkt_sched.h:120
 net_tx_action+0x717/0x900 net/core/dev.c:5782
 handle_softirqs+0x22b/0x7c0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x60/0x150 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lockdep_unregister_key+0x2ce/0x350 kernel/locking/lockdep.c:6616
Code: 41 5d 41 5e 41 5f 5d e9 50 f1 08 00 89 c7 e8 79 07 00 00 e9 6c fe ff ff e8 8f ae bb 09 41 f7 c7 00 02 00 00 74 bb fb 40 84 ed <75> ba eb cb 90 0f 0b 90 e9 2e ff ff ff 90 0f 0b 90 e9 36 ff ff ff
RSP: 0018:ffffc9000bf0f028 EFLAGS: 00000246
RAX: 0000000000000046 RBX: ffff888024194268 RCX: 0000000000000046
RDX: ffffffff95883468 RSI: ffffffff8d7a7209 RDI: ffffffff8bc08360
RBP: ffff888021a99e00 R08: ffffffff81ab3a98 R09: ffffffff8df41aa0
R10: dffffc0000000000 R11: ffffffff89631c90 R12: 0000000000000000
R13: ffff888024194269 R14: 0000000000001000 R15: 0000000000000a87
 __qdisc_destroy+0x166/0x400 net/sched/sch_generic.c:1079
 taprio_destroy+0x263/0x550 net/sched/sch_taprio.c:2043
 __qdisc_destroy+0x153/0x400 net/sched/sch_generic.c:1077
 taprio_attach+0x25a/0x380 net/sched/sch_taprio.c:2161
 qdisc_graft+0x1175/0x1590 net/sched/sch_api.c:1162
 __tc_modify_qdisc net/sched/sch_api.c:1761 [inline]
 tc_modify_qdisc+0x16d3/0x2020 net/sched/sch_api.c:1817
 rtnetlink_rcv_msg+0x77c/0xb70 net/core/rtnetlink.c:6967
 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+0x505/0x820 net/socket.c:2592
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2646
 __sys_sendmsg net/socket.c:2678 [inline]
 __do_sys_sendmsg net/socket.c:2683 [inline]
 __se_sys_sendmsg net/socket.c:2681 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2681
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f574438f749
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:00007f5745297038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f57445e6090 RCX: 00007f574438f749
RDX: 0000000000000000 RSI: 00002000000007c0 RDI: 0000000000000004
RBP: 00007f5744413f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f57445e6128 R14: 00007f57445e6090 R15: 00007ffc993a4658
 </TASK>
sched: DL replenish lagged too much