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WARNING: CPU: 0 PID: 7861 at kernel/rcu/tree_stall.h:1001 rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:993
Modules linked in:
CPU: 0 PID: 7861 Comm: syz.4.534 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:1001
Code: ff ff ff 48 c7 c7 a0 04 ef 96 be 04 00 00 00 e8 ba ac 6c 00 48 89 df b8 01 00 00 00 87 05 ac cc 7e 15 85 c0 0f 85 19 ff ff ff <0f> 0b 48 81 ff 80 50 d3 8c 74 47 48 c7 c0 5c c6 4a 8e 48 c1 e8 03
RSP: 0018:ffffc90000007bb8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffffffff8cd35080 RCX: ffffffff817037e6
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8cd35080
RBP: ffffc90000007e30 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff2dde094 R12: 0000000000002904
R13: 1ffff110171c7a22 R14: 0000000000000a02 R15: dffffc0000000000
FS: 00007f5b87d7a6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c40ff8d CR3: 000000006a3ec000 CR4: 00000000003506f0
Call Trace:
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
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:trace_sys_enter+0x64/0x80 include/trace/events/syscalls.h:18
Code: 91 7e 83 f8 08 73 38 89 c0 48 0f a3 05 fd 02 d8 0c 73 d6 65 ff 05 14 29 91 7e 48 8b 05 fd fd c2 0c 48 85 c0 74 09 48 8b 78 08 37 fb ff ff 65 ff 0d f8 28 91 7e 75 90 e8 49 0d 8e ff eb 89 0f
RSP: 0018:ffffc90003b17ee8 EFLAGS: 00000282
RAX: ffff8880253f1d10 RBX: ffffc90003b17f58 RCX: 9bd205fe66055700
RDX: 00000000000000ca RSI: ffffc90003b17f58 RDI: ffffc90003afb000
RBP: ffffc90003b17f48 R08: ffffffff8e4a91af R09: 1ffffffff1c95235
R10: dffffc0000000000 R11: fffffbfff1c95236 R12: ffff88802acada00
R13: 0000000000000000 R14: 0000000000000002 R15: 0000000000000000
syscall_trace_enter+0xf0/0x150 kernel/entry/common.c:81
do_syscall_64+0x28/0xb0 arch/x86/entry/common.c:77
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f5b86f8ec29
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:00007f5b87d7a0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f5b871d6098 RCX: 00007f5b86f8ec29
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f5b871d6098
RBP: 00007f5b871d6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5b871d6128 R14: 00007ffd44ee5f50 R15: 00007ffd44ee6038
----------------
Code disassembly (best guess):
0: 91 xchg %eax,%ecx
1: 7e 83 jle 0xffffff86
3: f8 clc
4: 08 73 38 or %dh,0x38(%rbx)
7: 89 c0 mov %eax,%eax
9: 48 0f a3 05 fd 02 d8 bt %rax,0xcd802fd(%rip) # 0xcd8030e
10: 0c
11: 73 d6 jae 0xffffffe9
13: 65 ff 05 14 29 91 7e incl %gs:0x7e912914(%rip) # 0x7e91292e
1a: 48 8b 05 fd fd c2 0c mov 0xcc2fdfd(%rip),%rax # 0xcc2fe1e
21: 48 85 c0 test %rax,%rax
24: 74 09 je 0x2f
26: 48 8b 78 08 mov 0x8(%rax),%rdi
* 2a: e8 37 fb ff ff call 0xfffffb66 <-- trapping instruction
2f: 65 ff 0d f8 28 91 7e decl %gs:0x7e9128f8(%rip) # 0x7e91292e
36: 75 90 jne 0xffffffc8
38: e8 49 0d 8e ff call 0xff8e0d86
3d: eb 89 jmp 0xffffffc8
3f: 0f .byte 0xf