Re: [RFC PATCH v2 04/26] KVM: arm64: Initialize kvm_nvhe_init_params early

[Will Deacon]

On Fri, Jan 08, 2021 at 12:15:02PM +0000, Quentin Perret wrote:
> Move the initialization of kvm_nvhe_init_params in a dedicated function
> that is run early, and only once during KVM init, rather than every time
> the KVM vectors are set and reset.
> 
> This also opens the opportunity for the hypervisor to change the init
> structs during boot, hence simplifying the replacement of host-provided
> page-tables and stacks by the ones the hypervisor will create for
> itself.
> 
> Signed-off-by: Quentin Perret <qperret@xxxxxxxxxx>
> ---
>  arch/arm64/kvm/arm.c | 28 ++++++++++++++++++++--------
>  1 file changed, 20 insertions(+), 8 deletions(-)
> 
> diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
> index 04c44853b103..3ac0f3425833 100644
> --- a/arch/arm64/kvm/arm.c
> +++ b/arch/arm64/kvm/arm.c

[...]

> @@ -1807,6 +1813,12 @@ static int init_hyp_mode(void)
>  			goto out_err;
>  	}
>  
> +	/*
> +	 * Prepare the CPU initialization parameters
> +	 */
> +	for_each_possible_cpu(cpu)
> +		cpu_prepare_hyp_mode(cpu);
> +

This is the fifth for_each_possible_cpu() loop in this function; can any of
them be merged together?

Will