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WARNING: CPU: 1 PID: 18921 at kernel/rcu/tree_stall.h:970 rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:962
Modules linked in:
CPU: 1 PID: 18921 Comm: syz.7.3197 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:970
Code: ff ff ff 48 c7 c7 20 2f c4 96 be 04 00 00 00 e8 ca 78 66 00 48 89 df b8 01 00 00 00 87 05 8c 26 57 15 85 c0 0f 85 19 ff ff ff <0f> 0b 48 81 ff 00 2b b3 8c 74 47 48 c7 c0 a4 13 20 8e 48 c1 e8 03
RSP: 0018:ffffc900001e0b78 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffffffff8cb32b00 RCX: ffffffff816d0886
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8cb32b00
RBP: ffffc900001e0df0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff2d885e4 R12: 0000000000002904
R13: dffffc0000000000 R14: 0000000000000a06 R15: dffffc0000000000
FS:  00007f46df9b46c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f804534da08 CR3: 0000000057cac000 CR4: 00000000003506e0
Call Trace:
 <IRQ>
 rcu_core+0x60b/0x1740 kernel/rcu/tree.c:2552
 handle_softirqs+0x2a1/0x930 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: 00 00 00 66 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 be e0 2c f7 48 89 df e8 06 a9 2d f7 e8 11 ff 50 f7 fb bf 01 00 00 00 <e8> 56 0d 21 f7 65 8b 05 a7 90 ca 75 85 c0 74 02 5b c3 e8 f4 a4 c8
RSP: 0018:ffffc9000d617b98 EFLAGS: 00000282
RAX: 1fe50bcb8f593300 RBX: ffff88802e47c0c0 RCX: 1fe50bcb8f593300
RDX: dffffc0000000000 RSI: ffffffff8a8c10a0 RDI: 0000000000000001
RBP: ffff88802e47c558 R08: ffff88802e47c0c3 R09: 1ffff11005c8f818
R10: dffffc0000000000 R11: ffffed1005c8f819 R12: 1ffff11005c8f8ab
R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x1163/0x1350 kernel/signal.c:2874
 arch_do_signal_or_restart+0xc4/0x1350 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f46e179c799
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:00007f46df9b40e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f46e1a16188 RCX: 00007f46e179c799
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f46e1a16188
RBP: 00007f46e1a16180 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f46e1a16218 R14: 00007ffc90114fa0 R15: 00007ffc90115088
 </TASK>
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	00 66 90             	add    %ah,-0x70(%rsi)
   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 be e0 2c f7       	call   0xf72ce0d5
  17:	48 89 df             	mov    %rbx,%rdi
  1a:	e8 06 a9 2d f7       	call   0xf72da925
  1f:	e8 11 ff 50 f7       	call   0xf750ff35
  24:	fb                   	sti
  25:	bf 01 00 00 00       	mov    $0x1,%edi
* 2a:	e8 56 0d 21 f7       	call   0xf7210d85 <-- trapping instruction
  2f:	65 8b 05 a7 90 ca 75 	mov    %gs:0x75ca90a7(%rip),%eax        # 0x75ca90dd
  36:	85 c0                	test   %eax,%eax
  38:	74 02                	je     0x3c
  3a:	5b                   	pop    %rbx
  3b:	c3                   	ret
  3c:	e8                   	.byte 0xe8
  3d:	f4                   	hlt
  3e:	a4                   	movsb  %ds:(%rsi),%es:(%rdi)
  3f:	c8                   	.byte 0xc8