On 15/05/12 22:03, Christoffer Dall wrote:
> On Mon, May 14, 2012 at 9:04 AM, Marc Zyngier <marc.zyngier at arm.com> wrote:
>> The ACTLR is implementation dependant, and better left untouched
>> by the guest.
>>
>> Trap the access by ignoring writes, and let reads return the host
>> view of the ACTLR, adjusted to reflect whether the guest is SMP
>> or not.
>>
>> Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
>> ---
>> arch/arm/include/asm/kvm_arm.h | 2 +-
>> arch/arm/kvm/emulate.c | 24 ++++++++++++++++++++++++
>> 2 files changed, 25 insertions(+), 1 deletions(-)
>>
>> diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h
>> index 29f3a36..b9e4197 100644
>> --- a/arch/arm/include/asm/kvm_arm.h
>> +++ b/arch/arm/include/asm/kvm_arm.h
>> @@ -49,7 +49,7 @@
>> #define HCR_SWIO (1 << 1)
>> #define HCR_VM 1
>> #define HCR_GUEST_MASK (HCR_TSC | HCR_TWI | HCR_VM | HCR_BSU_IS | HCR_FB | \
>> - HCR_AMO | HCR_IMO | HCR_FMO | HCR_SWIO)
>> + HCR_TAC | HCR_AMO | HCR_IMO | HCR_FMO | HCR_SWIO)
>> #define HCR_VIRT_EXCP_MASK (HCR_VA | HCR_VI | HCR_VF)
>>
>> /* Hyp System Control Register (HSCTLR) bits */
>> diff --git a/arch/arm/kvm/emulate.c b/arch/arm/kvm/emulate.c
>> index e356d1c..6eaa97d 100644
>> --- a/arch/arm/kvm/emulate.c
>> +++ b/arch/arm/kvm/emulate.c
>> @@ -238,6 +238,23 @@ static bool read_l2ctlr(struct kvm_vcpu *vcpu,
>> return true;
>> }
>>
>> +static bool read_actlr(struct kvm_vcpu *vcpu,
>> + const struct coproc_params *p,
>> + unsigned long arg)
>> +{
>> + u32 actlr;
>> +
>> + asm volatile("mrc p15, 0, %0, c1, c0, 1\n" : "=r" (actlr));
>> + /* Make the SMP bit consistent with the guest configuration */
>> + if (atomic_read(&vcpu->kvm->online_vcpus) > 1)
>> + actlr |= 1U << 6;
>
> should we not check the MIDR here since it's implementation defined?
> (refer to Russel's "Check the cpuid we're being asked to emulate"
> patch)
Indeed, that's a very good point. I'll respin that patch.
Thanks,
M.
--
Jazz is not dead. It just smells funny...
