From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rusty Russell <rusty.russell@linaro.org>
Subject: Re: [RFC 5/5] KVM: ARM: Access all registers via KVM_GET_ONE_REG/KVM_SET_ONE_REG.
Date: Thu, 30 Aug 2012 03:51:35 +0930
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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: Peter Maydell <peter.maydell@linaro.org>
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Peter Maydell <peter.maydell@linaro.org> writes:
> 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.

Avi wanted to get rid of the structures.

But I thought "it will never change" was already proven untrue, for your
psuedo-secure mode proposal?

>> +       /* 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.

OK, changed that too (16).

Thanks,
Rusty.