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WARNING: kernel/rcu/tree_stall.h:1088 at rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1088, CPU#0: syz.2.2735/15995
Modules linked in:
CPU: 0 UID: 0 PID: 15995 Comm: syz.2.2735 Tainted: G             L       syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1088
Code: ff ff 48 c7 c7 a0 8b a4 9a be 04 00 00 00 e8 e3 50 8c 00 4c 89 f7 b8 01 00 00 00 87 05 c5 a9 f6 18 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff 80 41 d6 8e 74 47 48 c7 c0 d0 4e 7a 90 48 c1 e8
RSP: 0018:ffffc90000007d98 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000246 RCX: ffffffff81ade1cd
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8ed64180
RBP: ffffc90000007f28 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff3549174 R12: 0000000000002904
R13: dffffc0000000000 R14: ffffffff8ed64180 R15: dffffc0000000000
FS:  00007f41b9bd96c0(0000) GS:ffff888124caf000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007faaf80422ec CR3: 0000000079a82000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 rcu_core+0x5c6/0x1260 kernel/rcu/tree.c:2914
 handle_softirqs+0x223/0x840 kernel/softirq.c:645
 __do_softirq kernel/softirq.c:679 [inline]
 invoke_softirq kernel/softirq.c:519 [inline]
 __irq_exit_rcu+0xcb/0x220 kernel/softirq.c:758
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:775
 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:220 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:229
Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 2a 86 b6 f5 48 89 df e8 e2 fd b6 f5 e8 9d 84 e3 f5 fb bf 01 00 00 00 <e8> 02 0d a8 f5 65 48 8b 05 aa 60 a9 07 48 85 c0 74 07 5b c3 cc cc
RSP: 0018:ffffc90004dbfc78 EFLAGS: 00000202
RAX: 000000000587c707 RBX: ffff88802bb44a00 RCX: 8000000000000001
RDX: 0000000000000000 RSI: ffffffff8e428461 RDI: 0000000000000001
RBP: 0000000000000000 R08: ffffffff907a1fbf R09: 1ffffffff20f43f7
R10: dffffc0000000000 R11: fffffbfff20f43f8 R12: 0000000000000021
R13: ffff88802bb44e98 R14: 000000001c000004 R15: dffffc0000000000
 spin_unlock_irq include/linux/spinlock.h:413 [inline]
 get_signal+0x1131/0x12c0 kernel/signal.c:3115
 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+0x10e/0x770 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:343 [inline]
 do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f41b8d9e157
Code: 83 c8 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
RSP: 002b:00007f41b9bd90e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007f41b9025fa8 RCX: 00007f41b8d9e159
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f41b9025fa8
RBP: 00007f41b9025fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f41b9026038 R14: 00007fff2bc66880 R15: 00007fff2bc66968
 </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 2a 86 b6 f5       	call   0xf5b68641
  17:	48 89 df             	mov    %rbx,%rdi
  1a:	e8 e2 fd b6 f5       	call   0xf5b6fe01
  1f:	e8 9d 84 e3 f5       	call   0xf5e384c1
  24:	fb                   	sti
  25:	bf 01 00 00 00       	mov    $0x1,%edi
* 2a:	e8 02 0d a8 f5       	call   0xf5a80d31 <-- trapping instruction
  2f:	65 48 8b 05 aa 60 a9 	mov    %gs:0x7a960aa(%rip),%rax        # 0x7a960e1
  36:	07
  37:	48 85 c0             	test   %rax,%rax
  3a:	74 07                	je     0x43
  3c:	5b                   	pop    %rbx
  3d:	c3                   	ret
  3e:	cc                   	int3
  3f:	cc                   	int3