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WARNING: kernel/rcu/tree_stall.h:1048 at rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1048, CPU#0: syz.5.2369/18233
Modules linked in:
CPU: 0 UID: 0 PID: 18233 Comm: syz.5.2369 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1048
Code: ff ff 48 c7 c7 e0 36 7c 9a be 04 00 00 00 e8 83 2e 88 00 4c 89 f7 b8 01 00 00 00 87 05 25 c5 cf 18 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff 00 f8 b5 8e 74 47 48 c7 c0 40 7b 57 90 48 c1 e8
RSP: 0018:ffffc90000007d98 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000246 RCX: ffffffff81ac71ad
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8eb5f800
RBP: ffffc90000007f20 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff34f86dc R12: 0000000000002904
R13: dffffc0000000000 R14: ffffffff8eb5f800 R15: dffffc0000000000
FS:  00007f361fc3b6c0(0000) GS:ffff888124f55000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000058 CR3: 0000000073f4b000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 rcu_core+0x414/0x10a0 kernel/rcu/tree.c:2892
 handle_softirqs+0x225/0x840 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:188 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:206
Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 4a 77 cf f5 48 89 df e8 a2 ec cf f5 e8 0d cd fb f5 fb bf 01 00 00 00 <e8> 52 00 c1 f5 65 8b 05 4b 40 99 07 85 c0 74 07 5b e9 1c d1 3c f5
RSP: 0018:ffffc900032a7c78 EFLAGS: 00000206
RAX: 00000000049c65b7 RBX: ffff88802e701bc0 RCX: 0000000080000001
RDX: 0000000000000000 RSI: ffffffff8e228edb RDI: 0000000000000001
RBP: 0000000000000000 R08: ffffffff90574837 R09: 1ffffffff20ae906
R10: dffffc0000000000 R11: fffffbfff20ae907 R12: 0000000000000011
R13: ffff88802e701e58 R14: 0000000004000000 R15: dffffc0000000000
 spin_unlock_irq include/linux/spinlock.h:402 [inline]
 get_signal+0x1136/0x12c0 kernel/signal.c:3049
 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
 exit_to_user_mode_loop+0x104/0x730 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f361ed9e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f361fc3b0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f361f025fa8 RCX: 00007f361ed9e0d9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f361f025fa8
RBP: 00007f361f025fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f361f026038 R14: 00007ffdabf11010 R15: 00007ffdabf110f8
 </TASK>
----------------
Code disassembly (best guess):
   0:	90                   	nop
   1:	f3 0f 1e fa          	endbr64
   5:	53                   	push   %rbx
   6:	48 89 fb             	mov    %rdi,%rbx
   9:	48 83 c7 18          	add    $0x18,%rdi
   d:	48 8b 74 24 08       	mov    0x8(%rsp),%rsi
  12:	e8 4a 77 cf f5       	call   0xf5cf7761
  17:	48 89 df             	mov    %rbx,%rdi
  1a:	e8 a2 ec cf f5       	call   0xf5cfecc1
  1f:	e8 0d cd fb f5       	call   0xf5fbcd31
  24:	fb                   	sti
  25:	bf 01 00 00 00       	mov    $0x1,%edi
* 2a:	e8 52 00 c1 f5       	call   0xf5c10081 <-- trapping instruction
  2f:	65 8b 05 4b 40 99 07 	mov    %gs:0x799404b(%rip),%eax        # 0x7994081
  36:	85 c0                	test   %eax,%eax
  38:	74 07                	je     0x41
  3a:	5b                   	pop    %rbx
  3b:	e9 1c d1 3c f5       	jmp    0xf53cd15c