Re: [PATCH v7 5/10] KVM: arm/arm64: preserve host MDCR_EL2 value

[Amit Daniel Kachhap]

Hi,

On 3/26/19 1:34 AM, Kristina Martsenko wrote:
> On 19/03/2019 08:30, Amit Daniel Kachhap wrote:
> > Save host MDCR_EL2 value during kvm HYP initialisation and restore
> > after every switch from host to guest. There should not be any
> > change in functionality due to this.
> >
> > The value of mdcr_el2 is now stored in struct kvm_cpu_context as
> > both host and guest can now use this field in a common way.
> >
> > Signed-off-by: Amit Daniel Kachhap <amit.kachhap@xxxxxxx>
> > Acked-by: Mark Rutland <mark.rutland@xxxxxxx>
> > Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
> > Cc: Mark Rutland <mark.rutland@xxxxxxx>
> > Cc: Christoffer Dall <christoffer.dall@xxxxxxx>
> > Cc: kvmarm@xxxxxxxxxxxxxxxxxxxxx
>
> [...]
>
> >   /**
> > - * kvm_arm_init_debug - grab what we need for debug
> > - *
> > - * Currently the sole task of this function is to retrieve the initial
> > - * value of mdcr_el2 so we can preserve MDCR_EL2.HPMN which has
> > - * presumably been set-up by some knowledgeable bootcode.
> > - *
> > - * It is called once per-cpu during CPU hyp initialisation.
> > - */
> > -
> > -void kvm_arm_init_debug(void)
> > -{
> > -	__this_cpu_write(mdcr_el2, kvm_call_hyp_ret(__kvm_get_mdcr_el2));
> > -}
>
> The __kvm_get_mdcr_el2 function is no longer used anywhere, so can also
> be removed.
Nice catch. Will do.

Thanks,
Amit D
> Thanks,
> Kristina