Re: [PATCH] xen/arm: Don't set the ACTLR SMP bit for 64 bit guests

[Julien Grall <julien.grall@linaro.org>]

On 09/03/2013 04:56 PM, Ian Campbell wrote:
> On Thu, 2013-08-29 at 18:28 +0100, Julien Grall wrote:
>> The ACTLR register is implementation defined. The SMP bit is CA15 and CA7
>> specific. Also replace ACTLR_CA15_SMP by ACTLR_V7_SMP.
>>
>> Signed-off-by: Julien Grall <julien.grall@linaro.org>
> 
> I'm afraid this breaks the arm64 build:
>         domain.c: In function 'vcpu_initialise':
>         domain.c:482:30: error: 'ACTLR_V7_SMP' undeclared (first use in this function)
>         domain.c:482:30: note: each undeclared identifier is reported only once for eac
>         h function it appears in
>         
> I'm not sure it is worth putting *that* much effort into a CA15/CA7
> kernel as a 32-bit guest on a 64-bit processor, at least not right now.
> The interesting use case of this support is really a 32-bit kernel which
> is aware that it is running in AArch32 EL1 on a 64-bit processor (i.e.
> knows about the 64-bit processors implementation specific stuff)
> 
> How about moving this into a proc info hook, or just ifdeffing it for
> 32-bit?

The first solution sounds better. I will rewrite the patch to add a proc
info hook.

-- 
Julien Grall