syzbot

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WARNING: CPU: 1 PID: 6840 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: 6840 Comm: syz.0.274 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:1001
Code: ff ff ff 48 c7 c7 a0 24 ef 96 be 04 00 00 00 e8 4a d0 6c 00 48 89 df b8 01 00 00 00 87 05 4c f4 7e 15 85 c0 0f 85 19 ff ff ff <0f> 0b 48 81 ff 80 51 d3 8c 74 47 48 c7 c0 ac c8 4a 8e 48 c1 e8 03
RSP: 0018:ffffc900001f0bb8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffffffff8cd35180 RCX: ffffffff81703046
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8cd35180
RBP: ffffc900001f0e30 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff2dde494 R12: 0000000000002904
R13: 1ffff110171e79e2 R14: 0000000000000a02 R15: dffffc0000000000
FS:  00007f59c697f6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc6dfeb1f40 CR3: 0000000031bf7000 CR4: 00000000003506e0
Call Trace:
 <IRQ>
 rcu_core+0x612/0x1720 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+0xc7/0x190 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:signal_setup_done+0x23b/0x310 kernel/signal.c:2951
Code: 75 3e bf 05 00 00 00 31 f6 48 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f 5d e9 93 c5 ff ff e8 6e 67 31 00 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 10 75 0f 48 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f 5d c3
RSP: 0018:ffffc9000c26fd30 EFLAGS: 00000293
RAX: 09e868c1108b3800 RBX: 0000000000000000 RCX: ffff88802c948000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000002 R08: ffffffff8e4a93ef R09: 1ffffffff1c9527d
R10: dffffc0000000000 R11: fffffbfff1c9527e R12: 1ffff1100592912c
R13: 0000000100000000 R14: ffff88802c948000 R15: ffff88802c948960
 handle_signal arch/x86/kernel/signal.c:285 [inline]
 arch_do_signal_or_restart+0x4a6/0x7b0 arch/x86/kernel/signal.c:312
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xf6/0x180 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+0x61/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f59c5bb7e80
Code: 83 c0 16 83 e0 f7 74 12 50 48 8d 3d 8a 54 08 00 e8 05 8f f8 ff 0f 1f 44 00 00 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <83> ff 21 74 0b c3 66 2e 0f 1f 84 00 00 00 00 00 55 53 48 89 f3 48
RSP: 002b:00007f59c697ea78 EFLAGS: 00000246 ORIG_RAX: 0000000000000013
RAX: 0000000000000000 RBX: 00007f59c5de5fa0 RCX: 00007f59c5b8f749
RDX: 00007f59c697ea80 RSI: 00007f59c697ebb0 RDI: 0000000000000021
RBP: 00007f59c5c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f59c5de6038 R14: 00007f59c5de5fa0 R15: 00007ffc1c049258
 </TASK>
----------------
Code disassembly (best guess):
   0:	75 3e                	jne    0x40
   2:	bf 05 00 00 00       	mov    $0x5,%edi
   7:	31 f6                	xor    %esi,%esi
   9:	48 83 c4 18          	add    $0x18,%rsp
   d:	5b                   	pop    %rbx
   e:	41 5c                	pop    %r12
  10:	41 5d                	pop    %r13
  12:	41 5e                	pop    %r14
  14:	41 5f                	pop    %r15
  16:	5d                   	pop    %rbp
  17:	e9 93 c5 ff ff       	jmp    0xffffc5af
  1c:	e8 6e 67 31 00       	call   0x31678f
  21:	65 48 8b 04 25 28 00 	mov    %gs:0x28,%rax
  28:	00 00
* 2a:	48 3b 44 24 10       	cmp    0x10(%rsp),%rax <-- trapping instruction
  2f:	75 0f                	jne    0x40
  31:	48 83 c4 18          	add    $0x18,%rsp
  35:	5b                   	pop    %rbx
  36:	41 5c                	pop    %r12
  38:	41 5d                	pop    %r13
  3a:	41 5e                	pop    %r14
  3c:	41 5f                	pop    %r15
  3e:	5d                   	pop    %rbp
  3f:	c3                   	ret