rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (1 GPs behind) idle=5dc4/1/0x4000000000000000 softirq=97724/97727 fqs=5245
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:     6035          0            0
rcu: 	cputime:      124      52375            3   ==> 52500(ms)
rcu: 	(t=10501 jiffies g=89157 q=2202 ncpus=2)
CPU: 0 UID: 0 PID: 21620 Comm: syz.2.3925 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 40 80 92 65 8b 0d a8 45 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:ffffc90000007cd0 EFLAGS: 00000246
RAX: ffffffff8970cf5c RBX: 000000000000000c RCX: 0000000000000100
RDX: ffff888065ec3d00 RSI: 000000000000000c RDI: 000000000000000a
RBP: 1ffff1100920c26a R08: ffffffff89702936 R09: ffffffff8df41aa0
R10: 0000000000000001 R11: ffffffff89635210 R12: dffffc0000000000
R13: ffff888049061354 R14: 000000000000000a R15: 0000000000000008
FS:  00007f1a2fdf66c0(0000) GS:ffff888125e1c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31d63fff CR3: 0000000032bce000 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:5795
 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:console_flush_one_record arch/x86/include/asm/irqflags.h:-1 [inline]
RIP: 0010:console_flush_all+0x7fc/0xb00 kernel/printk/printk.c:3289
Code: ff ff e8 b7 f9 1f 00 90 0f 0b 90 e9 85 fc ff ff e8 a9 f9 1f 00 e8 14 42 b9 09 48 85 db 74 c0 e8 9a f9 1f 00 fb 48 8b 5c 24 10 <48> 8b 44 24 20 42 80 3c 28 00 4c 8b 74 24 18 74 08 4c 89 f7 e8 6b
RSP: 0018:ffffc9000d676a20 EFLAGS: 00000283
RAX: ffffffff81a0ff16 RBX: ffffc9000d676b80 RCX: 0000000000080000
RDX: ffffc9001cb0f000 RSI: 0000000000002836 RDI: 0000000000002837
RBP: ffffc9000d676b30 R08: ffffffff8f823877 R09: 1ffffffff1f0470e
R10: dffffc0000000000 R11: fffffbfff1f0470f R12: 0000000000000001
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff8e792280
 __console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
 console_unlock+0xbb/0x190 kernel/printk/printk.c:3359
 vprintk_emit+0x47b/0x550 kernel/printk/printk.c:2426
 _printk+0xcf/0x120 kernel/printk/printk.c:2451
 validate_nla lib/nlattr.c:414 [inline]
 __nla_validate_parse+0x1719/0x2d40 lib/nlattr.c:635
 __nla_parse+0x40/0x60 lib/nlattr.c:732
 nla_parse_nested_deprecated include/net/netlink.h:1379 [inline]
 rtnl_newlink+0x7ac/0x1c90 net/core/rtnetlink.c:4019
 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6958
 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: 0033:0x7f1a31b8f749
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:00007f1a2fdf6038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f1a31de6090 RCX: 00007f1a31b8f749
RDX: 0000000000000000 RSI: 0000200000000080 RDI: 000000000000000a
RBP: 00007f1a31c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1a31de6128 R14: 00007f1a31de6090 R15: 00007ffe0601fe28
 </TASK>
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 21620 Comm: syz.2.3925 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:taprio_dequeue_tc_priority+0x247/0x750 net/sched/sch_taprio.c:798
Code: 93 01 00 00 45 89 75 00 4c 8b 7c 24 28 49 83 ff 10 4c 8b 74 24 30 0f 87 99 01 00 00 42 0f b6 44 25 00 84 c0 0f 85 33 02 00 00 <41> 8b 5d 00 4c 89 f0 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 39 02
RSP: 0018:ffffc90000007cd8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 000000000000000c RCX: 0000000000000100
RDX: ffff888065ec3d00 RSI: 000000000000000c RDI: 000000000000000c
RBP: 1ffff1100920c26a R08: ffffffff89702936 R09: ffffffff8df41aa0
R10: 0000000000000001 R11: ffffffff89635210 R12: dffffc0000000000
R13: ffff888049061354 R14: ffff8880651984c8 R15: 0000000000000002
FS:  00007f1a2fdf66c0(0000) GS:ffff888125e1c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31d63fff CR3: 0000000032bce000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 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:5795
 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:console_flush_one_record arch/x86/include/asm/irqflags.h:-1 [inline]
RIP: 0010:console_flush_all+0x7fc/0xb00 kernel/printk/printk.c:3289
Code: ff ff e8 b7 f9 1f 00 90 0f 0b 90 e9 85 fc ff ff e8 a9 f9 1f 00 e8 14 42 b9 09 48 85 db 74 c0 e8 9a f9 1f 00 fb 48 8b 5c 24 10 <48> 8b 44 24 20 42 80 3c 28 00 4c 8b 74 24 18 74 08 4c 89 f7 e8 6b
RSP: 0018:ffffc9000d676a20 EFLAGS: 00000283
RAX: ffffffff81a0ff16 RBX: ffffc9000d676b80 RCX: 0000000000080000
RDX: ffffc9001cb0f000 RSI: 0000000000002836 RDI: 0000000000002837
RBP: ffffc9000d676b30 R08: ffffffff8f823877 R09: 1ffffffff1f0470e
R10: dffffc0000000000 R11: fffffbfff1f0470f R12: 0000000000000001
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff8e792280
 __console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
 console_unlock+0xbb/0x190 kernel/printk/printk.c:3359
 vprintk_emit+0x47b/0x550 kernel/printk/printk.c:2426
 _printk+0xcf/0x120 kernel/printk/printk.c:2451
 validate_nla lib/nlattr.c:414 [inline]
 __nla_validate_parse+0x1719/0x2d40 lib/nlattr.c:635
 __nla_parse+0x40/0x60 lib/nlattr.c:732
 nla_parse_nested_deprecated include/net/netlink.h:1379 [inline]
 rtnl_newlink+0x7ac/0x1c90 net/core/rtnetlink.c:4019
 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6958
 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: 0033:0x7f1a31b8f749
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:00007f1a2fdf6038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f1a31de6090 RCX: 00007f1a31b8f749
RDX: 0000000000000000 RSI: 0000200000000080 RDI: 000000000000000a
RBP: 00007f1a31c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1a31de6128 R14: 00007f1a31de6090 R15: 00007ffe0601fe28
 </TASK>
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 21620 Comm: syz.2.3925 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:taprio_dequeue_tc_priority+0x25f/0x750 net/sched/sch_taprio.c:798
Code: 99 01 00 00 42 0f b6 44 25 00 84 c0 0f 85 33 02 00 00 41 8b 5d 00 4c 89 f0 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 39 02 00 00 <45> 8b 36 89 df 44 89 f6 e8 b4 2a 50 f8 44 39 f3 73 15 48 8b 5c 24
RSP: 0018:ffffc90000007cd8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000009 RCX: 0000000000000100
RDX: ffff888065ec3d00 RSI: 000000000000000c RDI: 0000000000000009
RBP: 1ffff1100920c26a R08: ffffffff89702936 R09: ffffffff8df41aa0
R10: 0000000000000001 R11: ffffffff89635210 R12: dffffc0000000000
R13: ffff888049061354 R14: ffff8880651984c8 R15: 0000000000000002
FS:  00007f1a2fdf66c0(0000) GS:ffff888125e1c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31d63fff CR3: 0000000032bce000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 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:5795
 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:console_flush_one_record arch/x86/include/asm/irqflags.h:-1 [inline]
RIP: 0010:console_flush_all+0x7fc/0xb00 kernel/printk/printk.c:3289
Code: ff ff e8 b7 f9 1f 00 90 0f 0b 90 e9 85 fc ff ff e8 a9 f9 1f 00 e8 14 42 b9 09 48 85 db 74 c0 e8 9a f9 1f 00 fb 48 8b 5c 24 10 <48> 8b 44 24 20 42 80 3c 28 00 4c 8b 74 24 18 74 08 4c 89 f7 e8 6b
RSP: 0018:ffffc9000d676a20 EFLAGS: 00000283
RAX: ffffffff81a0ff16 RBX: ffffc9000d676b80 RCX: 0000000000080000
RDX: ffffc9001cb0f000 RSI: 0000000000002836 RDI: 0000000000002837
RBP: ffffc9000d676b30 R08: ffffffff8f823877 R09: 1ffffffff1f0470e
R10: dffffc0000000000 R11: fffffbfff1f0470f R12: 0000000000000001
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff8e792280
 __console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
 console_unlock+0xbb/0x190 kernel/printk/printk.c:3359
 vprintk_emit+0x47b/0x550 kernel/printk/printk.c:2426
 _printk+0xcf/0x120 kernel/printk/printk.c:2451
 validate_nla lib/nlattr.c:414 [inline]
 __nla_validate_parse+0x1719/0x2d40 lib/nlattr.c:635
 __nla_parse+0x40/0x60 lib/nlattr.c:732
 nla_parse_nested_deprecated include/net/netlink.h:1379 [inline]
 rtnl_newlink+0x7ac/0x1c90 net/core/rtnetlink.c:4019
 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6958
 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: 0033:0x7f1a31b8f749
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:00007f1a2fdf6038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f1a31de6090 RCX: 00007f1a31b8f749
RDX: 0000000000000000 RSI: 0000200000000080 RDI: 000000000000000a
RBP: 00007f1a31c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1a31de6128 R14: 00007f1a31de6090 R15: 00007ffe0601fe28
 </TASK>