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WARNING: CPU: 1 PID: 6201 at kernel/rcu/tree_stall.h:937 rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:929
Modules linked in:
CPU: 1 PID: 6201 Comm: syz.4.435 Not tainted 5.15.186-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:937
Code: ff ff ff 48 c7 c7 00 6c 0e 96 be 04 00 00 00 e8 da 22 59 00 48 89 df b8 01 00 00 00 87 05 1c 51 aa 14 85 c0 0f 85 19 ff ff ff <0f> 0b 48 81 ff 00 04 12 8c 74 47 48 c7 c0 c4 df 68 8d 48 c1 e8 03
RSP: 0018:ffffc90000dd0bb8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffffffff8c120400 RCX: ffffffff81641ad6
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8c120400
RBP: ffffc90000dd0e10 R08: 0000000000000004 R09: 0000000000000003
R10: fffffbfff2c1cd80 R11: 1ffffffff2c1cd80 R12: 0000000000002904
R13: ffffffff8c120400 R14: 0000000000000a02 R15: dffffc0000000000
FS: 00007f761a8336c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3fe0da CR3: 0000000077c0a000 CR4: 00000000003506e0
Call Trace:
<IRQ>
rcu_core+0x5ef/0x15d0 kernel/rcu/tree.c:2758
handle_softirqs+0x328/0x820 kernel/softirq.c:576
__do_softirq kernel/softirq.c:610 [inline]
invoke_softirq kernel/softirq.c:450 [inline]
__irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659
irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f6 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 ee 69 b1 f7 48 89 df e8 b6 3e b2 f7 e8 f1 e3 d2 f7 fb bf 01 00 00 00 <e8> e6 62 a6 f7 65 8b 05 87 72 57 76 85 c0 74 02 5b c3 e8 34 7d 55
RSP: 0018:ffffc90002dbfcf0 EFLAGS: 00000286
RAX: e34000e51bb5d200 RBX: ffff88805d098940 RCX: e34000e51bb5d200
RDX: dffffc0000000000 RSI: ffffffff8a0b11c0 RDI: 0000000000000001
RBP: ffffc90002dbff10 R08: dffffc0000000000 R09: ffffed100ba13129
R10: ffffed100ba13129 R11: 1ffff1100ba13128 R12: ffff888022ff8000
R13: 1ffff920005b7ffe R14: 1ffff920005b7fa8 R15: ffffc90002dbfff0
__ia32_sys_rt_sigreturn+0x184/0x790 arch/x86/kernel/signal.c:672
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f761c967b19
Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25
RSP: 002b:00007f761a832b40 EFLAGS: 00000206 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00007f761cbf2fa8 RCX: 00007f761c967b19
RDX: 00007f761a832b40 RSI: 00007f761a832c70 RDI: 0000000000000021
RBP: 00007f761cbf2fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 00007f761cbf2fac
R13: 0000000000000000 R14: 00007ffda1ea6660 R15: 00007ffda1ea6748
</TASK>
----------------
Code disassembly (best guess):
0: f6 ff idiv %bh
2: 0f 1f 00 nopl (%rax)
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 ee 69 b1 f7 call 0xf7b16a05
17: 48 89 df mov %rbx,%rdi
1a: e8 b6 3e b2 f7 call 0xf7b23ed5
1f: e8 f1 e3 d2 f7 call 0xf7d2e415
24: fb sti
25: bf 01 00 00 00 mov $0x1,%edi
* 2a: e8 e6 62 a6 f7 call 0xf7a66315 <-- trapping instruction
2f: 65 8b 05 87 72 57 76 mov %gs:0x76577287(%rip),%eax # 0x765772bd
36: 85 c0 test %eax,%eax
38: 74 02 je 0x3c
3a: 5b pop %rbx
3b: c3 ret
3c: e8 .byte 0xe8
3d: 34 7d xor $0x7d,%al
3f: 55 push %rbp