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WARNING: kernel/rcu/tree_stall.h:1049 at rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1049, CPU#1: syz-executor/5843
Modules linked in:
CPU: 1 UID: 0 PID: 5843 Comm: syz-executor Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1049
Code: ff ff 48 c7 c7 c0 55 2c 9a be 04 00 00 00 e8 43 b6 84 00 4c 89 f7 b8 01 00 00 00 87 05 15 f7 80 18 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff 40 41 76 8e 74 47 48 c7 c0 c0 0b 12 90 48 c1 e8
RSP: 0000:ffffc90000a08db8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000246 RCX: ffffffff81ab5e9d
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8e764140
RBP: ffffc90000a08f28 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff3458ab8 R12: 0000000000002904
R13: dffffc0000000000 R14: ffffffff8e764140 R15: dffffc0000000000
FS:  000055557ab1b500(0000) GS:ffff888125554000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055557ab36a28 CR3: 0000000063b4a000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 rcu_core+0x3fe/0x1070 kernel/rcu/tree.c:2864
 handle_softirqs+0x22a/0x870 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x5f/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:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xce5/0x12c0 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 d4 eb 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 7f e7 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 63 e7
RSP: 0000:ffffc90004067820 EFLAGS: 00000293
RAX: ffffffff81b9d88d RBX: 1ffff110170c8525 RCX: ffff88807c999e80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90004067950 R08: ffffffff9011d8b7 R09: 1ffffffff2023b16
R10: dffffc0000000000 R11: fffffbfff2023b17 R12: ffff8880b8642928
R13: dffffc0000000000 R14: ffff8880b873c000 R15: 0000000000000000
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:57 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1382 [inline]
 flush_tlb_mm_range+0x5c3/0x10c0 arch/x86/mm/tlb.c:1472
 flush_tlb_page arch/x86/include/asm/tlbflush.h:323 [inline]
 ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:103
 wp_page_copy mm/memory.c:3846 [inline]
 do_wp_page+0x4129/0x5a00 mm/memory.c:4241
 handle_pte_fault mm/memory.c:6333 [inline]
 __handle_mm_fault mm/memory.c:6455 [inline]
 handle_mm_fault+0x1520/0x3310 mm/memory.c:6624
 do_user_addr_fault+0xa73/0x1340 arch/x86/mm/fault.c:1334
 handle_page_fault arch/x86/mm/fault.c:1474 [inline]
 exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f85373613a0
Code: ba 28 00 48 8d 0c 1e 49 39 d0 49 89 48 60 0f 95 c2 48 29 d8 0f b6 d2 48 83 c8 01 48 c1 e2 02 48 09 da 48 83 ca 01 48 89 56 08 <48> 89 41 08 48 8d 4e 10 eb b0 48 8d 0d 37 df 0c 00 ba 9e 10 00 00
RSP: 002b:00007f853773fc50 EFLAGS: 00010206
RAX: 00000000000185e1 RBX: 0000000000008040 RCX: 000055557ab36a20
RDX: 0000000000008041 RSI: 000055557ab2e9e0 RDI: 0000000000000004
RBP: 0000000000000802 R08: 00007f85375ece20 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000008030
R13: 0000000000000000 R14: 00007f85375ece80 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess):
   0:	45 8b 2c 24          	mov    (%r12),%r13d
   4:	44 89 ee             	mov    %r13d,%esi
   7:	83 e6 01             	and    $0x1,%esi
   a:	31 ff                	xor    %edi,%edi
   c:	e8 d4 eb 0b 00       	call   0xbebe5
  11:	41 83 e5 01          	and    $0x1,%r13d
  15:	49 bd 00 00 00 00 00 	movabs $0xdffffc0000000000,%r13
  1c:	fc ff df
  1f:	75 07                	jne    0x28
  21:	e8 7f e7 0b 00       	call   0xbe7a5
  26:	eb 38                	jmp    0x60
  28:	f3 90                	pause
* 2a:	42 0f b6 04 2b       	movzbl (%rbx,%r13,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	75 11                	jne    0x44
  33:	41 f7 04 24 01 00 00 	testl  $0x1,(%r12)
  3a:	00
  3b:	74 1e                	je     0x5b
  3d:	e8                   	.byte 0xe8
  3e:	63 e7                	movsxd %edi,%esp