From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Maydell <peter.maydell@linaro.org>
Subject: Re: [RFC 5/5] KVM: ARM: Access all registers via KVM_GET_ONE_REG/KVM_SET_ONE_REG.
Date: Wed, 29 Aug 2012 16:36:52 +0100
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Cc: Avi Kivity <avi@redhat.com>,
	Christoffer Dall <c.dall@virtualopensystems.com>,
	Alexander Graf <agraf@suse.de>, kvmarm@lists.cs.columbia.edu,
	kvm-devel <kvm@vger.kernel.org>
To: Rusty Russell <rusty.russell@linaro.org>
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On 29 August 2012 00:48, Rusty Russell <rusty.russell@linaro.org> wrote:
> No structures at all any more.

I'm not fussed whether we use structs for the core regs or
not; they're not exactly going to change in future so it's
purely a question of whether you think it's aesthetically
prettier to have everything funneled through the one ioctl.

> +       /* Coprocessor 0 means we want a core register. */
> +       if ((u32)reg->id >> KVM_REG_ARM_COPROC_START == 0)
> +               return set_core_reg(vcpu, reg);

...but if we do go this path, you can't use coprocessor 0
to mean core register -- cp0 could be a valid coprocessor
(the ARM ARM reserves cp0..cp7 for "vendor specific features").
Use something outside 0..15.

-- PMM