------------[ cut here ]------------
WARNING: net/mptcp/subflow.c:1527 at subflow_data_ready+0x40b/0x790 net/mptcp/subflow.c:1527, CPU#0: modprobe/1352
Modules linked in:
CPU: 0 UID: 0 PID: 1352 Comm: modprobe Tainted: G     U       L      syzkaller #0 PREEMPT(full) 
Tainted: [U]=USER, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:subflow_data_ready+0x40b/0x790 net/mptcp/subflow.c:1527
Code: 89 ee e8 f8 5b 5d f6 40 84 ed 75 21 e8 ae 61 5d f6 44 89 fe bf 07 00 00 00 e8 41 5c 5d f6 41 83 ff 07 74 09 e8 96 61 5d f6 90 <0f> 0b 90 e8 8d 61 5d f6 48 89 df e8 f5 ac ff ff 31 ff 89 c5 89 c6
RSP: 0000:ffffc90000007548 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88802990cc80 RCX: ffffffff8b60f71f
RDX: ffff888033d59e80 RSI: ffffffff8b60f72a RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000007
R10: 0000000000000004 R11: ffff888033d5a9b0 R12: ffff888058542400
R13: 1ffff92000000ea9 R14: ffff88805a83dc00 R15: 0000000000000004
FS:  00007f479a290c80(0000) GS:ffff8881248fd000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f479a333000 CR3: 00000000598fc000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 tcp_data_ready+0x114/0x5a0 net/ipv4/tcp_input.c:5371
 tcp_data_queue+0x1ac2/0x4ff0 net/ipv4/tcp_input.c:5461
 tcp_rcv_state_process+0xfb6/0x6540 net/ipv4/tcp_input.c:7185
 tcp_v4_do_rcv+0x68e/0x10a0 net/ipv4/tcp_ipv4.c:1904
 tcp_v4_rcv+0x3077/0x4db0 net/ipv4/tcp_ipv4.c:2324
 ip_protocol_deliver_rcu+0xba/0x4c0 net/ipv4/ip_input.c:207
 ip_local_deliver_finish+0x3f2/0x720 net/ipv4/ip_input.c:241
 NF_HOOK include/linux/netfilter.h:318 [inline]
 NF_HOOK include/linux/netfilter.h:312 [inline]
 ip_local_deliver+0x18e/0x1f0 net/ipv4/ip_input.c:262
 dst_input include/net/dst.h:474 [inline]
 ip_rcv_finish net/ipv4/ip_input.c:453 [inline]
 NF_HOOK include/linux/netfilter.h:318 [inline]
 NF_HOOK include/linux/netfilter.h:312 [inline]
 ip_rcv+0x2e0/0x600 net/ipv4/ip_input.c:573
 __netif_receive_skb_one_core+0x197/0x1e0 net/core/dev.c:6137
 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6250
 process_backlog+0x4a2/0x1650 net/core/dev.c:6602
 __napi_poll.constprop.0+0xb3/0x540 net/core/dev.c:7666
 napi_poll net/core/dev.c:7729 [inline]
 net_rx_action+0x9f9/0xfa0 net/core/dev.c:7881
 handle_softirqs+0x219/0x950 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x109/0x170 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+0xa4/0xc0 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:write_comp_data+0x42/0x90 kernel/kcov.c:246
Code: a9 00 01 ff 00 74 1d f6 c4 01 74 67 a9 00 00 0f 00 75 60 a9 00 00 f0 00 75 59 8b 82 6c 16 00 00 85 c0 74 4f 8b 82 48 16 00 00 <83> f8 03 75 44 48 8b 82 50 16 00 00 8b 92 4c 16 00 00 48 8b 38 48
RSP: 0000:ffffc900053b7910 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 000000000008dd3a RCX: ffffffff82337c82
RDX: ffff888033d59e80 RSI: 000fffffffffffff RDI: 0000000000000007
RBP: 000fffffffffffff R08: 0000000000000007 R09: 000fffffffffffff
R10: 000000000008dd3a R11: ffff888033d5a9b0 R12: 0000000000000000
R13: 0000000000000001 R14: dffffc0000000000 R15: 0000000000000000
 pfn_valid include/linux/mmzone.h:2177 [inline]
 page_table_check_set+0x32/0xa40 mm/page_table_check.c:105
 __page_table_check_ptes_set+0x276/0x4e0 mm/page_table_check.c:212
 page_table_check_ptes_set include/linux/page_table_check.h:76 [inline]
 set_ptes include/linux/pgtable.h:292 [inline]
 set_pte_range+0x5be/0xa50 mm/memory.c:5483
 filemap_map_order0_folio mm/filemap.c:3856 [inline]
 filemap_map_pages+0x6af/0x1e00 mm/filemap.c:3921
 do_fault_around mm/memory.c:5713 [inline]
 do_read_fault mm/memory.c:5746 [inline]
 do_fault+0x9cd/0x1ad0 mm/memory.c:5889
 do_pte_missing mm/memory.c:4401 [inline]
 handle_pte_fault mm/memory.c:6273 [inline]
 __handle_mm_fault+0x1919/0x2bb0 mm/memory.c:6411
 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6580
 do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1336
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x64/0xc0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f479a333000
Code: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 <48> 83 ec 08 48 8b 05 cd af 00 00 48 85 c0 74 02 ff d0 48 83 c4 08
RSP: 002b:00007ffe592e4618 EFLAGS: 00010206
RAX: 00007f479a333000 RBX: 00007f479a5fc580 RCX: 00007ffe592e46c0
RDX: 00007ffe592e46c0 RSI: 00007ffe592e4698 RDI: 0000000000000004
RBP: 0000000000000004 R08: 00000000000001e0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe592e4698
R13: 00007ffe592e46c0 R14: 00007f479a63b310 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess):
   0:	a9 00 01 ff 00       	test   $0xff0100,%eax
   5:	74 1d                	je     0x24
   7:	f6 c4 01             	test   $0x1,%ah
   a:	74 67                	je     0x73
   c:	a9 00 00 0f 00       	test   $0xf0000,%eax
  11:	75 60                	jne    0x73
  13:	a9 00 00 f0 00       	test   $0xf00000,%eax
  18:	75 59                	jne    0x73
  1a:	8b 82 6c 16 00 00    	mov    0x166c(%rdx),%eax
  20:	85 c0                	test   %eax,%eax
  22:	74 4f                	je     0x73
  24:	8b 82 48 16 00 00    	mov    0x1648(%rdx),%eax
* 2a:	83 f8 03             	cmp    $0x3,%eax <-- trapping instruction
  2d:	75 44                	jne    0x73
  2f:	48 8b 82 50 16 00 00 	mov    0x1650(%rdx),%rax
  36:	8b 92 4c 16 00 00    	mov    0x164c(%rdx),%edx
  3c:	48 8b 38             	mov    (%rax),%rdi
  3f:	48                   	rex.W