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WARNING: CPU: 0 PID: 5103 at kernel/rcu/tree_stall.h:970 rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:962
Modules linked in:
CPU: 0 PID: 5103 Comm: syz.4.157 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:970
Code: ff ff ff 48 c7 c7 20 3f a1 96 be 04 00 00 00 e8 3a 5d 65 00 48 89 df b8 01 00 00 00 87 05 8c 89 35 15 85 c0 0f 85 19 ff ff ff <0f> 0b 48 81 ff 80 06 93 8c 74 47 48 c7 c0 e4 42 ff 8d 48 c1 e8 03
RSP: 0018:ffffc90000007b78 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffffffff8c930680 RCX: ffffffff816bb586
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8c930680
RBP: ffffc90000007df0 R08: 0000000000000004 R09: 0000000000000003
R10: fffffbfff2d427e4 R11: 1ffffffff2d427e4 R12: 0000000000002904
R13: dffffc0000000000 R14: 0000000000000a06 R15: dffffc0000000000
FS:  00007f54406426c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f846f5db000 CR3: 000000007dcb8000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rcu_core+0x5d9/0x16a0 kernel/rcu/tree.c:2552
 handle_softirqs+0x2a1/0x920 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x12f/0x220 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:should_fail_ex+0x33/0x4d0 lib/fault-inject.c:119
Code: 53 48 83 ec 18 89 14 24 49 89 f6 48 89 fb 49 bc 00 00 00 00 00 fc ff df 65 8b 05 a0 ab d7 7b a9 00 01 ff 00 0f 84 ed 00 00 00 <49> 89 dd 49 c1 ed 03 43 80 7c 25 00 00 74 08 48 89 df e8 56 4d a6
RSP: 0018:ffffc900032e7af0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffff8cfc2cc0 RCX: 0000000000080000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff8cfc2cc0
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff5200065cf90
R10: fffff5200065cf90 R11: 1ffff9200065cf8a R12: dffffc0000000000
R13: 1ffff110053de670 R14: 0000000000000001 R15: ffff888029ef3384
 __copy_from_user include/linux/uaccess.h:77 [inline]
 check_xstate_in_sigframe arch/x86/kernel/fpu/signal.c:35 [inline]
 __fpu_restore_sig arch/x86/kernel/fpu/signal.c:348 [inline]
 fpu__restore_sig+0x215/0x1190 arch/x86/kernel/fpu/signal.c:493
 restore_sigcontext arch/x86/kernel/signal.c:140 [inline]
 __ia32_sys_rt_sigreturn+0x649/0x790 arch/x86/kernel/signal.c:675
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f543f78f749
Code: 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 01 48
RSP: 002b:00007f54406420e8 EFLAGS: 00000246
RAX: fffffffffffffffc RBX: 00007f543f9e6098 RCX: 00007f543f78f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f543f9e6098
RBP: 00007f543f9e6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f543f9e6128 R14: 00007ffdfa671720 R15: 00007ffdfa671808
 </TASK>
----------------
Code disassembly (best guess):
   0:	53                   	push   %rbx
   1:	48 83 ec 18          	sub    $0x18,%rsp
   5:	89 14 24             	mov    %edx,(%rsp)
   8:	49 89 f6             	mov    %rsi,%r14
   b:	48 89 fb             	mov    %rdi,%rbx
   e:	49 bc 00 00 00 00 00 	movabs $0xdffffc0000000000,%r12
  15:	fc ff df
  18:	65 8b 05 a0 ab d7 7b 	mov    %gs:0x7bd7aba0(%rip),%eax        # 0x7bd7abbf
  1f:	a9 00 01 ff 00       	test   $0xff0100,%eax
  24:	0f 84 ed 00 00 00    	je     0x117
* 2a:	49 89 dd             	mov    %rbx,%r13 <-- trapping instruction
  2d:	49 c1 ed 03          	shr    $0x3,%r13
  31:	43 80 7c 25 00 00    	cmpb   $0x0,0x0(%r13,%r12,1)
  37:	74 08                	je     0x41
  39:	48 89 df             	mov    %rbx,%rdi
  3c:	e8                   	.byte 0xe8
  3d:	56                   	push   %rsi
  3e:	4d a6                	rex.WRB cmpsb %es:(%rdi),%ds:(%rsi)