Subject: [PATCH v4 06/19] arm/arm64: KVM: move kvm_register_device_ops() into vGIC probing

From: [email-masked] (Andre Przywara)
Date: Tue, 18 Nov 2014 11:03:19 +0000

Hi Eric,

thanks for the review! Much appreciated.

On 18/11/14 10:58, Eric Auger wrote:
> On 11/18/2014 11:43 AM, Eric Auger wrote:
>> On 11/14/2014 11:07 AM, Andre Przywara wrote:
>>> Currently we unconditionally register the GICv2 emulation device
>>> during the host's KVM initialization. Since with GICv3 support we
>>> may end up with only v2 or only v3 or both supported, we move the
>>> registration into the GIC probing function, where we will later know
>>> which combination is valid.
>>>
>>> Signed-off-by: Andre Przywara <[email-masked]>
>>> Acked-by: Christoffer Dall <[email-masked]>
>>> ---
>>> Changelog v3...v4:
>>> - add Acked-by
>>>
>>>  include/linux/kvm_host.h |    1 +
>>>  virt/kvm/arm/vgic-v2.c   |    2 ++
>>>  virt/kvm/arm/vgic-v3.c   |    1 +
>>>  virt/kvm/arm/vgic.c      |    5 ++---
>>>  4 files changed, 6 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
>>> index ea53b04..326ba7a 100644
>>> --- a/include/linux/kvm_host.h
>>> +++ b/include/linux/kvm_host.h
>>> @@ -1084,6 +1084,7 @@ void kvm_unregister_device_ops(u32 type);
>>>  
>>>  extern struct kvm_device_ops kvm_mpic_ops;
>>>  extern struct kvm_device_ops kvm_xics_ops;
>>> +extern struct kvm_device_ops kvm_arm_vgic_v2_ops;
>>>  
>>>  #ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
>>>  
>>> diff --git a/virt/kvm/arm/vgic-v2.c b/virt/kvm/arm/vgic-v2.c
>>> index 2935405..e1cd3cb 100644
>>> --- a/virt/kvm/arm/vgic-v2.c
>>> +++ b/virt/kvm/arm/vgic-v2.c
>>> @@ -229,6 +229,8 @@ int vgic_v2_probe(struct device_node *vgic_node,
>>>  		goto out_unmap;
>>>  	}
>>>  
>>> +	kvm_register_device_ops(&kvm_arm_vgic_v2_ops, KVM_DEV_TYPE_ARM_VGIC_V2);
>>> +
>>>  	vgic->vcpu_base = vcpu_res.start;
>>>  
>>>  	kvm_info("%s@%llx IRQ%d\n", vgic_node->name,
>>> diff --git a/virt/kvm/arm/vgic-v3.c b/virt/kvm/arm/vgic-v3.c
>>> index 1c2c8ee..d14c75f 100644
>>> --- a/virt/kvm/arm/vgic-v3.c
>>> +++ b/virt/kvm/arm/vgic-v3.c
>>> @@ -230,6 +230,7 @@ int vgic_v3_probe(struct device_node *vgic_node,
>>>  		ret = -ENXIO;
>>>  		goto out;
>>>  	}
>>> +	kvm_register_device_ops(&kvm_arm_vgic_v2_ops, KVM_DEV_TYPE_ARM_VGIC_V2);
>> I did not find any unregistration? I am wrong or isn't it relevant? If
>> confirmed might be added in kvm_arch_exit. Saw KVM-VFIO device ops
>> unregistration is done in kvm_exit/kvm_vfio_ops_exit.
> 
> well forget that one. I guess it is not relevant for that device which
> is not going to be released.

Yeah, I think that's due to the fact that we cannot remove KVM from the
kernel on ARM (no modprobe -r).

Cheers,
Andre.

> BR
> 
> Eric
>>
>> Eric
>>>  
>>>  	vgic->vcpu_base = vcpu_res.start;
>>>  	vgic->vctrl_base = NULL;
>>> diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
>>> index 963b84e..e8003ca 100644
>>> --- a/virt/kvm/arm/vgic.c
>>> +++ b/virt/kvm/arm/vgic.c
>>> @@ -2540,7 +2540,7 @@ static int vgic_create(struct kvm_device *dev, u32 type)
>>>  	return kvm_vgic_create(dev->kvm, type);
>>>  }
>>>  
>>> -static struct kvm_device_ops kvm_arm_vgic_v2_ops = {
>>> +struct kvm_device_ops kvm_arm_vgic_v2_ops = {
>>>  	.name = "kvm-arm-vgic",
>>>  	.create = vgic_create,
>>>  	.destroy = vgic_destroy,
>>> @@ -2619,8 +2619,7 @@ int kvm_vgic_hyp_init(void)
>>>  
>>>  	on_each_cpu(vgic_init_maintenance_interrupt, NULL, 1);
>>>  
>>> -	return kvm_register_device_ops(&kvm_arm_vgic_v2_ops,
>>> -				       KVM_DEV_TYPE_ARM_VGIC_V2);
>>> +	return 0;
>>>  
>>>  out_free_irq:
>>>  	free_percpu_irq(vgic->maint_irq, kvm_get_running_vcpus());
>>>
>>
> 
>