------------[ cut here ]------------
WARNING: CPU: 1 PID: 9402 at kernel/rcu/tree_stall.h:989 rcu_check_gp_start_stall.part.0+0x1c4/0x4b0 kernel/rcu/tree_stall.h:989
Modules linked in:
CPU: 1 UID: 0 PID: 9402 Comm: syz.3.882 Not tainted 6.15.0-rc6-syzkaller-00346-g5723cc3450bc #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:rcu_check_gp_start_stall.part.0+0x1c4/0x4b0 kernel/rcu/tree_stall.h:989
Code: 88 61 01 00 00 be 04 00 00 00 48 c7 c7 60 d5 b3 9a e8 d0 60 7f 00 b8 01 00 00 00 87 05 25 69 12 19 85 c0 0f 85 3d 01 00 00 90 <0f> 0b 90 48 c7 c3 b4 5d 85 90 48 81 fd c0 a9 3c 8e 74 5a 48 b8 00
RSP: 0018:ffffc90000a08df0 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000002904 RCX: ffffffff81a16c30
RDX: fffffbfff3567aac RSI: 0000000000000004 RDI: ffffffff9ab3d560
RBP: ffffffff8e3ca9c0 R08: 0000000000000001 R09: fffffbfff3567aac
R10: 0000000000000003 R11: 0000000000000000 R12: 1ffffffff1c02240
R13: 0000000000000246 R14: ffffffff8e3ca9c0 R15: ffff8880b853ad92
FS:  00007f7c11dc16c0(0000) GS:ffff888124ada000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000001b3030 CR3: 000000003244a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rcu_check_gp_start_stall kernel/rcu/tree_stall.h:952 [inline]
 rcu_core+0x4cf/0x14e0 kernel/rcu/tree.c:2819
 handle_softirqs+0x216/0x8e0 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0x4a5/0x1290 kernel/smp.c:885
Code: 89 ee e8 de 12 0c 00 85 ed 74 48 48 8b 44 24 20 49 89 c4 83 e0 07 49 c1 ec 03 48 89 c5 4d 01 f4 83 c5 03 e8 7d 17 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 de 0b 00 00 8b 43 08 31
RSP: 0018:ffffc9001073f358 EFLAGS: 00000246
RAX: 0000000000080000 RBX: ffff8880b8441720 RCX: ffffc9000f696000
RDX: 0000000000080000 RSI: ffffffff81af2e73 RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffed10170882e5
R13: 0000000000000001 R14: dffffc0000000000 R15: ffff8880b853b040
 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1052
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1291 [inline]
 flush_tlb_mm_range+0x322/0x1780 arch/x86/mm/tlb.c:1381
 flush_tlb_page arch/x86/include/asm/tlbflush.h:324 [inline]
 ptep_clear_flush+0x136/0x180 mm/pgtable-generic.c:101
 wp_page_copy mm/memory.c:3544 [inline]
 do_wp_page+0x17cb/0x5930 mm/memory.c:3939
 handle_pte_fault mm/memory.c:6013 [inline]
 __handle_mm_fault+0x1ada/0x2a40 mm/memory.c:6140
 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6309
 do_user_addr_fault+0x7a6/0x1370 arch/x86/mm/fault.c:1388
 handle_page_fault arch/x86/mm/fault.c:1480 [inline]
 exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0010:__put_user_nocheck_4+0x3/0x10 arch/x86/lib/putuser.S:104
Code: d9 0f 01 cb 89 01 31 c9 0f 01 ca e9 47 54 03 00 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 01 cb <89> 01 31 c9 0f 01 ca c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9001073f9f8 EFLAGS: 00050246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00002000001b3030
RDX: 0000000000080000 RSI: ffffffff893e3b63 RDI: 0000000000000005
RBP: ffffc9001073fd98 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000
R13: 00002000001b3000 R14: ffffc9001073fddc R15: 0000000000000002
 ____sys_recvmsg+0x2ee/0x6b0 net/socket.c:2799
 ___sys_recvmsg+0x114/0x1a0 net/socket.c:2828
 do_recvmmsg+0x2fe/0x740 net/socket.c:2923
 __sys_recvmmsg net/socket.c:2997 [inline]
 __do_sys_recvmmsg net/socket.c:3020 [inline]
 __se_sys_recvmmsg net/socket.c:3013 [inline]
 __x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3013
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7c10f8e969
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:00007f7c11dc1038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f7c111b6160 RCX: 00007f7c10f8e969
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000005
RBP: 00007f7c11010ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f7c111b6160 R15: 00007ffd1f7e91b8
 </TASK>
----------------
Code disassembly (best guess):
   0:	89 ee                	mov    %ebp,%esi
   2:	e8 de 12 0c 00       	call   0xc12e5
   7:	85 ed                	test   %ebp,%ebp
   9:	74 48                	je     0x53
   b:	48 8b 44 24 20       	mov    0x20(%rsp),%rax
  10:	49 89 c4             	mov    %rax,%r12
  13:	83 e0 07             	and    $0x7,%eax
  16:	49 c1 ec 03          	shr    $0x3,%r12
  1a:	48 89 c5             	mov    %rax,%rbp
  1d:	4d 01 f4             	add    %r14,%r12
  20:	83 c5 03             	add    $0x3,%ebp
  23:	e8 7d 17 0c 00       	call   0xc17a5
  28:	f3 90                	pause
* 2a:	41 0f b6 04 24       	movzbl (%r12),%eax <-- trapping instruction
  2f:	40 38 c5             	cmp    %al,%bpl
  32:	7c 08                	jl     0x3c
  34:	84 c0                	test   %al,%al
  36:	0f 85 de 0b 00 00    	jne    0xc1a
  3c:	8b 43 08             	mov    0x8(%rbx),%eax
  3f:	31                   	.byte 0x31