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WARNING: CPU: 1 PID: 6397 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: 6397 Comm: syz.4.92 Not tainted 6.6.101-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:1001
Code: ff ff ff 48 c7 c7 a0 c4 ee 96 be 04 00 00 00 e8 2a a8 6c 00 48 89 df b8 01 00 00 00 87 05 4c 8f 7e 15 85 c0 0f 85 19 ff ff ff <0f> 0b 48 81 ff 00 54 d3 8c 74 47 48 c7 c0 9c b9 4a 8e 48 c1 e8 03
RSP: 0018:ffffc900001f0bb8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffffffff8cd35400 RCX: ffffffff81703546
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8cd35400
RBP: ffffc900001f0e30 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff2ddd894 R12: 0000000000002904
R13: 1ffff110171e7a6a R14: 0000000000000a02 R15: dffffc0000000000
FS: 00007f56b1d116c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000006b000 CR3: 00000000229e7000 CR4: 00000000003506e0
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:__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: 00 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 9a c8 f0 f6 48 89 df e8 b2 9a f1 f6 e8 4d 37 15 f7 fb bf 01 00 00 00 92 b2 e4 f6 65 8b 05 93 f8 8c 75 85 c0 74 02 5b c3 e8 70 da 89
RSP: 0018:ffffc90003927c98 EFLAGS: 00000282
RAX: 3740cfa035218000 RBX: ffff88802c7a1bc0 RCX: 3740cfa035218000
RDX: dffffc0000000000 RSI: ffffffff8aaaba40 RDI: 0000000000000001
RBP: ffff88802c7a2058 R08: ffffffff8e4a84ef R09: 1ffffffff1c9509d
R10: dffffc0000000000 R11: fffffbfff1c9509e R12: 1ffff110058f440b
R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000
spin_unlock_irq include/linux/spinlock.h:401 [inline]
get_signal+0x11f5/0x1400 kernel/signal.c:2905
arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xb1/0x140 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: 0033:0x7f56b0f8ebe9
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:00007f56b1d11038 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f56b11b5fa0 RCX: 00007f56b0f8ebe9
RDX: 000020000006b000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f56b1011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f56b11b6038 R14: 00007f56b11b5fa0 R15: 00007ffcbb7934f8
----------------
Code disassembly (best guess):
0: 00 f3 add %dh,%bl
2: 0f 1e fa nop %edx
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 9a c8 f0 f6 call 0xf6f0c8b1
17: 48 89 df mov %rbx,%rdi
1a: e8 b2 9a f1 f6 call 0xf6f19ad1
1f: e8 4d 37 15 f7 call 0xf7153771
24: fb sti
25: bf 01 00 00 00 mov $0x1,%edi
* 2a: e8 92 b2 e4 f6 call 0xf6e4b2c1 <-- trapping instruction
2f: 65 8b 05 93 f8 8c 75 mov %gs:0x758cf893(%rip),%eax # 0x758cf8c9
36: 85 c0 test %eax,%eax
38: 74 02 je 0x3c
3a: 5b pop %rbx
3b: c3 ret
3c: e8 .byte 0xe8
3d: 70 da jo 0x19
3f: 89 .byte 0x89