Re: [PATCH] KVM: Loongarch: Remove undefined a6 argument comment for kvm_hypercall

[Huacai Chen]

On Fri, Jul 26, 2024 at 9:49 AM maobibo <maobibo@xxxxxxxxxxx> wrote:
>
>
>
> On 2024/7/25 下午9:48, Dandan Zhang wrote:
> > The kvm_hypercall set for LoongArch is limited to a1-a5.
> > The mention of a6 in the comment is undefined that needs to be rectified.
> >
> > Signed-off-by: Wentao Guan <guanwentao@xxxxxxxxxxxxx>
> > Signed-off-by: Dandan Zhang <zhangdandan@xxxxxxxxxxxxx>
> > ---
> >   arch/loongarch/include/asm/kvm_para.h | 4 ++--
> >   1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/loongarch/include/asm/kvm_para.h b/arch/loongarch/include/asm/kvm_para.h
> > index 335fb86778e2..43ec61589e6c 100644
> > --- a/arch/loongarch/include/asm/kvm_para.h
> > +++ b/arch/loongarch/include/asm/kvm_para.h
> > @@ -39,9 +39,9 @@ struct kvm_steal_time {
> >    * Hypercall interface for KVM hypervisor
> >    *
> >    * a0: function identifier
> > - * a1-a6: args
> > + * a1-a5: args
> >    * Return value will be placed in a0.
> > - * Up to 6 arguments are passed in a1, a2, a3, a4, a5, a6.
> > + * Up to 5 arguments are passed in a1, a2, a3, a4, a5.
> >    */
> >   static __always_inline long kvm_hypercall0(u64 fid)
> >   {
> >
>
> Dandan,
>
> Nice catch. In future hypercall abi may expand such as the number of
> input register and output register, or async hypercall function if there
> is really such requirement.
>
> Anyway the modification is deserved and it is enough to use now, thanks
> for doing it.
>
> Reviewed-by: Bibo Mao <maobibo@xxxxxxxxxxx>
Maybe it is better to implement kvm_hypercall6() than remove a6 now?

Huacai
>