Re: [PATCH resend] KVM: ARM: enable Cortex A7 hosts

[Marc Zyngier <marc.zyngier@arm.com>]

On 26/09/13 15:41, Christoffer Dall wrote:
> On Thu, Sep 26, 2013 at 01:48:51PM +0200, Ulrich Hecht wrote:
>> KVM runs fine on Cortex A7 cores, so they should be enabled. Tested on an
>> APE6EVM board (r8a73a4 SoC).
>>
>> Signed-off-by: Ulrich Hecht <ulrich.hecht@gmail.com>
>> ---
>>  arch/arm/kvm/guest.c | 2 ++
>>  1 file changed, 2 insertions(+)
>>
>> diff --git a/arch/arm/kvm/guest.c b/arch/arm/kvm/guest.c
>> index 152d036..05c62d5 100644
>> --- a/arch/arm/kvm/guest.c
>> +++ b/arch/arm/kvm/guest.c
>> @@ -192,6 +192,8 @@ int __attribute_const__ kvm_target_cpu(void)
>>  	switch (part_number) {
>>  	case ARM_CPU_PART_CORTEX_A15:
>>  		return KVM_ARM_TARGET_CORTEX_A15;
>> +	case ARM_CPU_PART_CORTEX_A7:
>> +		return KVM_ARM_TARGET_CORTEX_A15;
>>  	default:
>>  		return -EINVAL;
>>  	}
>> -- 
>> 1.8.3.1
>>
> 
> nack
> 
> we need to have support and implementation for A7 cores and not try to
> shoehorn A7 support by pretending that it's an A15.
> 
> The fact that you have tested this and it happens to work with the
> workload you ran does not mean it is the right solution.  At the very
> least, you need to document and think about the different system
> register implementation and deal with them correctly.

Not to mention that supporting Cortex-A7 requires some generic KVM/ARM
fixes to work properly.

I believe Jonny is going to post these patches shortly, along with a
more compelling set of changes to support Cortex-A7.

Cheers,

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