[PATCH v3 02/17] KVM: arm64: nv: Allocate VNCR page when required

[Marc Zyngier]

On Fri, 09 May 2025 11:11:16 +0100,
Oliver Upton <oliver.upton at linux.dev> wrote:
> 
> On Wed, Apr 23, 2025 at 04:14:53PM +0100, Marc Zyngier wrote:
> > If running a NV guest on an ARMv8.4-NV capable system, let's
> > allocate an additional page that will be used by the hypervisor
> > to fulfill system register accesses.
> > 
> > Reviewed-by: Ganapatrao Kulkarni <gankulkarni at os.amperecomputing.com>
> > Signed-off-by: Marc Zyngier <maz at kernel.org>
> > ---
> >  arch/arm64/kvm/nested.c | 9 +++++++++
> >  arch/arm64/kvm/reset.c  | 1 +
> >  2 files changed, 10 insertions(+)
> > 
> > diff --git a/arch/arm64/kvm/nested.c b/arch/arm64/kvm/nested.c
> > index 4a3fc11f7ecf3..884b3e25795c4 100644
> > --- a/arch/arm64/kvm/nested.c
> > +++ b/arch/arm64/kvm/nested.c
> > @@ -55,6 +55,12 @@ int kvm_vcpu_init_nested(struct kvm_vcpu *vcpu)
> >  	    !cpus_have_final_cap(ARM64_HAS_HCR_NV1))
> >  		return -EINVAL;
> >  
> > +	if (!vcpu->arch.ctxt.vncr_array)
> > +		vcpu->arch.ctxt.vncr_array = (u64 *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
> 
> Think you want GFP_KERNEL_ACCOUNT here.

Yup, good point. I'll fold that in.

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.