Re: [PATCH 1/4] KVM: x86: hyper-v: Drop redundant 'ex' parameter from kvm_hv_send_ipi()

Maxim Levitsky
2022-02-25T18:21:35Z

On Tue, 2022-02-22 at 16:46 +0100, Vitaly Kuznetsov wrote:
> 'struct kvm_hv_hcall' has all the required information already,
> there's no need to pass 'ex' additionally.
>
> No functional change intended.
>
> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
> ---
> arch/x86/kvm/hyperv.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
> index 6e38a7d22e97..15b6a7bd2346 100644
> --- a/arch/x86/kvm/hyperv.c
> +++ b/arch/x86/kvm/hyperv.c
> @@ -1875,7 +1875,7 @@ static void kvm_send_ipi_to_many(struct kvm *kvm, u32 vector,
> }
> }
>
> -static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool ex)
> +static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
> {
> struct kvm *kvm = vcpu->kvm;
> struct hv_send_ipi_ex send_ipi_ex;
> @@ -1889,7 +1889,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool
> u32 vector;
> bool all_cpus;
>
> - if (!ex) {
> + if (hc->code == HVCALL_SEND_IPI) {

I am thinking, if we already touch this code,
why not to use switch here instead on the hc->code,
so that we can catch this function being called with something else than
HVCALL_SEND_IPI_EX

> if (!hc->fast) {
> if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi,
> sizeof(send_ipi))))
> @@ -2279,14 +2279,14 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
> ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
> break;
> }
> - ret = kvm_hv_send_ipi(vcpu, &hc, false);
> + ret = kvm_hv_send_ipi(vcpu, &hc);
> break;
> case HVCALL_SEND_IPI_EX:
> if (unlikely(hc.fast || hc.rep)) {
> ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
> break;
> }
> - ret = kvm_hv_send_ipi(vcpu, &hc, true);
> + ret = kvm_hv_send_ipi(vcpu, &hc);
> break;
> case HVCALL_POST_DEBUG_DATA:
> case HVCALL_RETRIEVE_DEBUG_DATA:

Other than this minor nitpick:

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>

Best regards,
Maxim Levitsky