------------[ cut here ]------------
WARNING: CPU: 1 PID: 6727 at kernel/rcu/tree_stall.h:1001 rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:993
Modules linked in:
CPU: 1 PID: 6727 Comm: syz.2.251 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:1001
Code: ff ff ff 48 c7 c7 a0 e4 30 97 be 04 00 00 00 e8 6a de 6d 00 48 89 df b8 01 00 00 00 87 05 7c 67 bf 15 85 c0 0f 85 19 ff ff ff <0f> 0b 48 81 ff 00 73 13 8d 74 47 48 c7 c0 ac 49 8b 8e 48 c1 e8 03
RSP: 0018:ffffc900001f0bb8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffffffff8d137300 RCX: ffffffff81717d16
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8d137300
RBP: ffffc900001f0e30 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff2e61c94 R12: 0000000000002904
R13: ffffffff8d137300 R14: 0000000000000a02 R15: dffffc0000000000
FS:  00007f84ece6f6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000006b000 CR3: 0000000051529000 CR4: 00000000003506e0
Call Trace:
 <IRQ>
 rcu_core+0x635/0x1770 kernel/rcu/tree.c:2462
 handle_softirqs+0x280/0x820 kernel/softirq.c:578
 __do_softirq kernel/softirq.c:612 [inline]
 invoke_softirq kernel/softirq.c:452 [inline]
 __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202
Code: 00 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 ea a7 d8 f6 48 89 df e8 a2 7c d9 f6 e8 1d 8f fd f6 fb bf 01 00 00 00 <e8> 82 83 cc f6 65 8b 05 c3 b0 73 75 85 c0 74 02 5b c3 e8 40 98 70
RSP: 0018:ffffc90004acfc78 EFLAGS: 00000286
RAX: b5f72c342f192400 RBX: ffff88805b6dc0c0 RCX: b5f72c342f192400
RDX: dffffc0000000000 RSI: ffffffff8acac9e0 RDI: 0000000000000001
RBP: ffff88805b6dc558 R08: ffffffff8e8b14ef R09: 1ffffffff1d1629d
R10: dffffc0000000000 R11: fffffbfff1d1629e R12: 1ffff1100b6db8ab
R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x11f5/0x13f0 kernel/signal.c:2905
 arch_do_signal_or_restart+0xc2/0x800 arch/x86/kernel/signal.c:310
 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:291 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f84ebe62b04
Code: 5d 41 5c 41 5e c3 48 8b 44 24 20 48 8b 5c 24 08 48 8b b0 88 00 00 00 8b 78 08 48 8d 53 30 e8 d3 3b ff ff 48 89 83 88 00 00 00 <e9> 35 fe ff ff 0f 1f 80 00 00 00 00 8b 7c 24 1c 48 8d 74 24 50 ba
RSP: 002b:00007f84ece6f050 EFLAGS: 00000206
RAX: 0000000000000000 RBX: 00007f84ec215fa0 RCX: 00007f84ec032c91
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f84ec032c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f84ec216038 R14: 00007f84ec215fa0 R15: 00007ffeab26aa68
 </TASK>
----------------
Code disassembly (best guess):
   0:	00 f3                	add    %dh,%bl
   2:	0f 1e fa             	nop    %edx
   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 ea a7 d8 f6       	call   0xf6d8a801
  17:	48 89 df             	mov    %rbx,%rdi
  1a:	e8 a2 7c d9 f6       	call   0xf6d97cc1
  1f:	e8 1d 8f fd f6       	call   0xf6fd8f41
  24:	fb                   	sti
  25:	bf 01 00 00 00       	mov    $0x1,%edi
* 2a:	e8 82 83 cc f6       	call   0xf6cc83b1 <-- trapping instruction
  2f:	65 8b 05 c3 b0 73 75 	mov    %gs:0x7573b0c3(%rip),%eax        # 0x7573b0f9
  36:	85 c0                	test   %eax,%eax
  38:	74 02                	je     0x3c
  3a:	5b                   	pop    %rbx
  3b:	c3                   	ret
  3c:	e8                   	.byte 0xe8
  3d:	40 98                	rex cwtl
  3f:	70                   	.byte 0x70