------------[ cut here ]------------
WARNING: kernel/rcu/tree_stall.h:1050 at rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1050, CPU#0: syz.6.5867/29086
Modules linked in:
CPU: 0 UID: 0 PID: 29086 Comm: syz.6.5867 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1050
Code: ff ff 48 c7 c7 60 d5 85 99 be 04 00 00 00 e8 93 1d 80 00 4c 89 f7 b8 01 00 00 00 87 05 d5 7a dd 17 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff c0 2c f4 8d 74 47 48 c7 c0 a0 1b 7e 8f 48 c1 e8
RSP: 0018:ffffc90000007bb8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000a02 RCX: ffffffff81a85a7d
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8df42cc0
RBP: ffffc90000007e30 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff330baac R12: 0000000000002904
R13: 1ffff110170c771a R14: ffffffff8df42cc0 R15: dffffc0000000000
FS:  00007fd62626f6c0(0000) GS:ffff888125eba000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdade271000 CR3: 000000004bc62000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 rcu_core+0x5fa/0x1770 kernel/rcu/tree.c:2856
 handle_softirqs+0x27d/0x880 kernel/softirq.c:626
 __do_softirq kernel/softirq.c:660 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:727
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:743
 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:__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: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 8a 34 40 f6 48 89 df e8 c2 cb 40 f6 e8 9d 3f 6b f6 fb bf 01 00 00 00 <e8> 32 b6 32 f6 65 8b 05 db ed 17 07 85 c0 74 07 5b e9 81 4d 00 00
RSP: 0018:ffffc9000466fc60 EFLAGS: 00000286
RAX: 9ca1729fa69bed00 RBX: ffff8880349ee5c0 RCX: 9ca1729fa69bed00
RDX: 0000000000000000 RSI: ffffffff8d78f71d RDI: 0000000000000001
RBP: 0000000000000021 R08: ffffffff8f7deb77 R09: 1ffffffff1efbd6e
R10: dffffc0000000000 R11: fffffbfff1efbd6f R12: 1ffff1100693dd4b
R13: 0000000000000000 R14: 000000001c000004 R15: ffff8880349eea58
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x11a7/0x1340 kernel/signal.c:3037
 arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x2e9/0xfa0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd62538f747
Code: ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89
RSP: 002b:00007fd62626f0e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007fd6255e6188 RCX: 00007fd62538f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fd6255e6188
RBP: 00007fd6255e6180 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd6255e6218 R14: 00007ffd94337ec0 R15: 00007ffd94337fa8
 </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 8a 34 40 f6       	call   0xf64034a1
  17:	48 89 df             	mov    %rbx,%rdi
  1a:	e8 c2 cb 40 f6       	call   0xf640cbe1
  1f:	e8 9d 3f 6b f6       	call   0xf66b3fc1
  24:	fb                   	sti
  25:	bf 01 00 00 00       	mov    $0x1,%edi
* 2a:	e8 32 b6 32 f6       	call   0xf632b661 <-- trapping instruction
  2f:	65 8b 05 db ed 17 07 	mov    %gs:0x717eddb(%rip),%eax        # 0x717ee11
  36:	85 c0                	test   %eax,%eax
  38:	74 07                	je     0x41
  3a:	5b                   	pop    %rbx
  3b:	e9 81 4d 00 00       	jmp    0x4dc1