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Re: [PATCH v2 10/21] arm64: KVM: VHE: Split save/restore of sysregs shared between EL1 and EL2

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On 01/02/16 13:54, Christoffer Dall wrote:
> On Mon, Jan 25, 2016 at 03:53:44PM +0000, Marc Zyngier wrote:
>> A handful of system registers are still shared between EL1 and EL2,
>> even while using VHE. These are tpidr*_el[01], actlr_el1, sp0, elr,
>> and spsr.
> 
> So by shared registers you mean registers that do both have an EL0/1
> version as well as an EL2 version, but where accesses aren't rewritten
> transparently?

No, I mean that these registers do *not* have a separate banked version.
There is only a single set of registers, which have to be save/restored
the old way.

> 
> also, by sp0 do you mean sp_el0, and by elr you mean elr_el1, and by
> spsr you mean spsr_el1 ?

sp0 -> sp_el0 indeed. elr and spsr really are the guest PC and PSTATE,
so I should really reword this commit message, it is utterly confusing.

> 
>>
>> In order to facilitate the introduction of a VHE-specific sysreg
>> save/restore, make move the access to these registers to their
>> own save/restore functions.
>>
>> No functionnal change.
> 
> Otherwise:
> 
> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...

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Re: [PATCH v2 10/21] arm64: KVM: VHE: Split save/restore of sysregs  shared between EL1 and EL2 Christoffer Dall <christoffer.dall@linaro.org> - 2016-02-01 15:00 +0100
  Re: [PATCH v2 10/21] arm64: KVM: VHE: Split save/restore of sysregs  shared between EL1 and EL2 Marc Zyngier <marc.zyngier@arm.com> - 2016-02-02 10:50 +0100
    Re: [PATCH v2 10/21] arm64: KVM: VHE: Split save/restore of sysregs  shared between EL1 and EL2 Christoffer Dall <christoffer.dall@linaro.org> - 2016-02-02 16:50 +0100
      Re: [PATCH v2 10/21] arm64: KVM: VHE: Split save/restore of sysregs  shared between EL1 and EL2 Marc Zyngier <marc.zyngier@arm.com> - 2016-02-02 17:20 +0100
        Re: [PATCH v2 10/21] arm64: KVM: VHE: Split save/restore of sysregs  shared between EL1 and EL2 Christoffer Dall <christoffer.dall@linaro.org> - 2016-02-02 21:10 +0100

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