'lapic_irq' is a local variable and its 'level' field isn't initialized, so 'level' is random, it doesn't matter but makes UBSAN unhappy: UBSAN: Undefined behaviour in .../lapic.c:... load of value 10 is not a valid value for type '_Bool' ... Call Trace: [<ffffffff81f030b6>] dump_stack+0x1e/0x20 [<ffffffff81f03173>] ubsan_epilogue+0x12/0x55 [<ffffffff81f03b96>] __ubsan_handle_load_invalid_value+0x118/0x162 [<ffffffffa1575173>] kvm_apic_set_irq+0xc3/0xf0 [kvm] [<ffffffffa1575b20>] kvm_irq_delivery_to_apic_fast+0x450/0x910 [kvm] [<ffffffffa15858ea>] kvm_irq_delivery_to_apic+0xfa/0x7a0 [kvm] [<ffffffffa1517f4e>] kvm_emulate_hypercall+0x62e/0x760 [kvm] [<ffffffffa113141a>] handle_vmcall+0x1a/0x30 [kvm_intel] [<ffffffffa114e592>] vmx_handle_exit+0x7a2/0x1fa0 [kvm_intel] ... Signed-off-by: Longpeng(Mike) <longpeng2@xxxxxxxxxx> --- arch/x86/kvm/x86.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 6c97c82..b411f92 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6215,6 +6215,7 @@ static void kvm_pv_kick_cpu_op(struct kvm *kvm, unsigned long flags, int apicid) lapic_irq.shorthand = 0; lapic_irq.dest_mode = 0; + lapic_irq.level = 0; lapic_irq.dest_id = apicid; lapic_irq.msi_redir_hint = false; -- 1.8.3.1