Re: [PATCH 2/2] KVM: arm64: Remove extra argument for __pvkm_host_{share,unshare}_hyp()

[Marc Zyngier <maz@kernel.org>]

On Wed, 10 Dec 2025 13:21:02 +0000,
Alexandru Elisei <alexandru.elisei@arm.com> wrote:
> 
> __pvkm_host_share_hyp() and __pkvm_host_unshare_hyp() both have one
> parameter, the pfn, not two. Even though correctness isn't impacted because
> the SMCCC handlers pass the first argument and ignore the second one, let's
> call the functions with the proper number of arguments.
> 
> Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
> ---
>  arch/arm64/kvm/mmu.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
> index 7cc964af8d30..6c6abcd8e89e 100644
> --- a/arch/arm64/kvm/mmu.c
> +++ b/arch/arm64/kvm/mmu.c
> @@ -497,7 +497,7 @@ static int share_pfn_hyp(u64 pfn)
>  	this->count = 1;
>  	rb_link_node(&this->node, parent, node);
>  	rb_insert_color(&this->node, &hyp_shared_pfns);
> -	ret = kvm_call_hyp_nvhe(__pkvm_host_share_hyp, pfn, 1);
> +	ret = kvm_call_hyp_nvhe(__pkvm_host_share_hyp, pfn);
>  unlock:
>  	mutex_unlock(&hyp_shared_pfns_lock);
>  

Yeah, we lost all form of type-checking when everything was hastily
converted to SMCCC to avoid function pointers. Somehow, I feel that
the cure was worse than the disease.

I wish we'd reintroduce some form of compile-time checks, maybe by
having generated stubs?

Thanks,

	M.

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