------------[ cut here ]------------
WARNING: CPU: 0 PID: 13 at kernel/rcu/tree_stall.h:1050 rcu_check_gp_start_stall.part.0+0x1c4/0x4b0 kernel/rcu/tree_stall.h:1050
Modules linked in:
CPU: 0 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 08/18/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:rcu_check_gp_start_stall.part.0+0x1c4/0x4b0 kernel/rcu/tree_stall.h:1050
Code: 88 61 01 00 00 be 04 00 00 00 48 c7 c7 80 10 8a 9a e8 60 e3 82 00 b8 01 00 00 00 87 05 35 65 e9 18 85 c0 0f 85 3d 01 00 00 90 <0f> 0b 90 48 c7 c3 f4 c7 5f 90 48 81 fd c0 d1 1c 8e 74 5a 48 b8 00
RSP: 0018:ffffc90000007df0 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000002904 RCX: ffffffff81a0ab40
RDX: fffffbfff3514210 RSI: 0000000000000004 RDI: ffffffff9a8a1080
RBP: ffffffff8e1cd1c0 R08: 0000000000000001 R09: fffffbfff3514210
R10: 0000000000000003 R11: 0000000000000000 R12: 1ffffffff1bc2240
R13: 0000000000000246 R14: ffffffff8e1cd1c0 R15: ffff8880b863b312
FS: 0000000000000000(0000) GS:ffff888124e77000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31f21ff8 CR3: 000000000df80000 CR4: 00000000003526f0
Call Trace:
rcu_check_gp_start_stall kernel/rcu/tree_stall.h:1013 [inline]
rcu_core+0x4cf/0x1530 kernel/rcu/tree.c:2856
handle_softirqs+0x219/0x8e0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x109/0x170 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1052
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xdfd/0x1600 kernel/smp.c:877
Code: 57 48 8b 54 24 10 4c 89 74 24 10 49 89 d5 48 89 d5 48 89 54 24 18 49 c1 ed 03 83 e5 07 4d 01 e5 83 c5 03 e8 b5 0c 0c 00 f3 90 <41> 0f b6 45 00 40 38 c5 7c 08 84 c0 0f 85 e0 05 00 00 8b 43 08 31
RSP: 0018:ffffc90000127888 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b87402e0 RCX: ffffffff81af06a1
RDX: ffff88801d6f8000 RSI: ffffffff81af067b RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: dffffc0000000000
R13: ffffed10170e805d R14: 0000000000000001 R15: 0000000000000001
on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1043
on_each_cpu include/linux/smp.h:71 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2653 [inline]
smp_text_poke_batch_finish+0x27b/0xdb0 arch/x86/kernel/alternative.c:2863
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
jump_label_update+0x376/0x550 kernel/jump_label.c:919
static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate mm/kfence/core.c:852 [inline]
toggle_allocation_gate+0xfa/0x280 mm/kfence/core.c:844
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3263
process_scheduled_works kernel/workqueue.c:3346 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x56d/0x730 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
----------------
Code disassembly (best guess):
0: 57 push %rdi
1: 48 8b 54 24 10 mov 0x10(%rsp),%rdx
6: 4c 89 74 24 10 mov %r14,0x10(%rsp)
b: 49 89 d5 mov %rdx,%r13
e: 48 89 d5 mov %rdx,%rbp
11: 48 89 54 24 18 mov %rdx,0x18(%rsp)
16: 49 c1 ed 03 shr $0x3,%r13
1a: 83 e5 07 and $0x7,%ebp
1d: 4d 01 e5 add %r12,%r13
20: 83 c5 03 add $0x3,%ebp
23: e8 b5 0c 0c 00 call 0xc0cdd
28: f3 90 pause
* 2a: 41 0f b6 45 00 movzbl 0x0(%r13),%eax <-- trapping instruction
2f: 40 38 c5 cmp %al,%bpl
32: 7c 08 jl 0x3c
34: 84 c0 test %al,%al
36: 0f 85 e0 05 00 00 jne 0x61c
3c: 8b 43 08 mov 0x8(%rbx),%eax
3f: 31 .byte 0x31