Re: [PATCH] KVM: x86: remove duplicated KVM_REQ_EVENT request

From: Vitaly Kuznetsov
Date: Thu Feb 06 2020 - 05:41:30 EST


linmiaohe <linmiaohe@xxxxxxxxxx> writes:

> From: Miaohe Lin <linmiaohe@xxxxxxxxxx>
>
> The KVM_REQ_EVENT request is already made in kvm_set_rflags(). We should
> not make it again.
>
> Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
> ---
> arch/x86/kvm/x86.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index fbabb2f06273..212282c6fb76 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -8942,7 +8942,6 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int idt_index,
>
> kvm_rip_write(vcpu, ctxt->eip);
> kvm_set_rflags(vcpu, ctxt->eflags);
> - kvm_make_request(KVM_REQ_EVENT, vcpu);

I would've actually done it the other way around and removed
kvm_make_request() from kvm_set_rflags() as it is not an obvious
behavior (e.g. why kvm_rip_write() doens't do that and kvm_set_rflags()
does ?) adding kvm_make_request() to all call sites.

In case this looks like too big of a change with no particular gain I'd
suggest you at least leave a comment above kvm_set_rflags(), something
like

"kvm_make_request() also requests KVM_REQ_EVENT"

> return 1;
> }
> EXPORT_SYMBOL_GPL(kvm_task_switch);

--
Vitaly