Re: [RFC PATCH v2 16/26] KVM: arm64: Prepare Hyp memory protection

From: Will Deacon
Date: Tue Feb 09 2021 - 07:24:00 EST


On Tue, Feb 09, 2021 at 10:00:29AM +0000, Quentin Perret wrote:
> On Thursday 04 Feb 2021 at 10:47:08 (+0000), Quentin Perret wrote:
> > On Wednesday 03 Feb 2021 at 14:37:10 (+0000), Will Deacon wrote:
> > > > +static void handle___pkvm_init(struct kvm_cpu_context *host_ctxt)
> > > > +{
> > > > + DECLARE_REG(phys_addr_t, phys, host_ctxt, 1);
> > > > + DECLARE_REG(unsigned long, size, host_ctxt, 2);
> > > > + DECLARE_REG(unsigned long, nr_cpus, host_ctxt, 3);
> > > > + DECLARE_REG(unsigned long *, per_cpu_base, host_ctxt, 4);
> > > > +
> > > > + cpu_reg(host_ctxt, 1) = __pkvm_init(phys, size, nr_cpus, per_cpu_base);
> > >
> > > __pkvm_init() doesn't return, so I think this assignment back into host_ctxt
> > > is confusing.
> >
> > Very good point, I'll get rid of this.
>
> Actually not, I think I'll leave it like that. __pkvm_init can return an
> error, which is why I did this in the first place And it is useful for
> debugging to have it propagated back to the host.

Good point, but please add a comment!

Will