2015-06-04 11:07:10

by Christoffer Dall

[permalink] [raw]
Subject: Re: [PATCH v5 05/12] KVM: arm: introduce kvm_arm_init/setup/clear_debug

On Fri, May 29, 2015 at 10:30:21AM +0100, Alex Benn?e wrote:
> This is a precursor for later patches which will need to do more to
> setup debug state before entering the hyp.S switch code. The existing
> functionality for setting mdcr_el2 has been moved out of hyp.S and now
> uses the value kept in vcpu->arch.mdcr_el2.
>
> As the assembler used to previously mask and preserve MDCR_EL2.HPMN I've
> had to add a mechanism to save the value of mdcr_el2 as a per-cpu
> variable during the initialisation code. The kernel never sets this
> number so we are assuming the bootcode has set up the correct value
> here.
>
> This also moves the conditional setting of the TDA bit from the hyp code
> into the C code which is currently used for the lazy debug register
> context switch code.
>
> Signed-off-by: Alex Benn?e <[email protected]>
>
Reviewed-by: Christoffer Dall <[email protected]>