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WARNING: kernel/rcu/tree_stall.h:1048 at rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1048, CPU#1: kworker/u8:1/13
Modules linked in:
CPU: 1 UID: 0 PID: 13 Comm: kworker/u8:1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1048
Code: ff ff 48 c7 c7 e0 06 7c 9a be 04 00 00 00 e8 53 22 88 00 4c 89 f7 b8 01 00 00 00 87 05 95 27 d0 18 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff 00 f8 b5 8e 74 47 48 c7 c0 00 aa 57 90 48 c1 e8
RSP: 0018:ffffc90000a08d98 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000246 RCX: ffffffff81abdf3d
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8eb5f800
RBP: ffffc90000a08f20 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff34f80dc R12: 0000000000002904
R13: dffffc0000000000 R14: ffffffff8eb5f800 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888125058000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa3405d4ff8 CR3: 000000000e946000 CR4: 00000000003526f0
Call Trace:
rcu_core+0x414/0x10a0 kernel/rcu/tree.c:2892
handle_softirqs+0x225/0x840 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xca/0x220 kernel/softirq.c:735
irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0x10b0/0x14b0 kernel/smp.c:892
Code: c0 75 73 41 8b 1e 89 de 83 e6 01 31 ff e8 d8 1e 0c 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 84 1a 0c 00 eb 37 f3 90 <41> 0f b6 04 1c 84 c0 75 10 41 f7 06 01 00 00 00 74 1e e8 69 1a 0c
RSP: 0018:ffffc90000127720 EFLAGS: 00000293
RAX: ffffffff81ba57d7 RBX: dffffc0000000000 RCX: ffff88801dec5d00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000127860 R08: ffffffff905776f7 R09: 1ffffffff20aeede
R10: dffffc0000000000 R11: fffffbfff20aeedf R12: 1ffff110170c85fd
R13: ffff8880b873c448 R14: ffff8880b8642fe8 R15: 0000000000000000
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
on_each_cpu include/linux/smp.h:72 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2773 [inline]
smp_text_poke_batch_finish+0x5fd/0x1110 arch/x86/kernel/alternative.c:2983
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate+0xab/0x290 mm/kfence/core.c:911
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
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Code disassembly (best guess):
0: c0 75 73 41 shlb $0x41,0x73(%rbp)
4: 8b 1e mov (%rsi),%ebx
6: 89 de mov %ebx,%esi
8: 83 e6 01 and $0x1,%esi
b: 31 ff xor %edi,%edi
d: e8 d8 1e 0c 00 call 0xc1eea
12: 83 e3 01 and $0x1,%ebx
15: 48 bb 00 00 00 00 00 movabs $0xdffffc0000000000,%rbx
1c: fc ff df
1f: 75 07 jne 0x28
21: e8 84 1a 0c 00 call 0xc1aaa
26: eb 37 jmp 0x5f
28: f3 90 pause
* 2a: 41 0f b6 04 1c movzbl (%r12,%rbx,1),%eax <-- trapping instruction
2f: 84 c0 test %al,%al
31: 75 10 jne 0x43
33: 41 f7 06 01 00 00 00 testl $0x1,(%r14)
3a: 74 1e je 0x5a
3c: e8 .byte 0xe8
3d: 69 .byte 0x69
3e: 1a .byte 0x1a
3f: 0c .byte 0xc