Subject: [PATCH v2] virt: kvm: arm: vgic: Process the failure case when kvm_register_device_ops() fails

From: [email-masked] (Chen Gang)
Date: Sat, 15 Nov 2014 00:30:11 +0800

According to your taste, we need improve 2 contents below:

On 11/14/2014 11:55 PM, Marc Zyngier wrote:
> 
> No. This is completely overdesigned, and fixes something that really
> cannot happen. What is wrong with:
> 
> diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
> index 3aaca49..b7dffa80 100644
> --- a/virt/kvm/arm/vgic.c
> +++ b/virt/kvm/arm/vgic.c
> @@ -2465,13 +2465,17 @@ int kvm_vgic_hyp_init(void)
>  		goto out_free_irq;
>  	}
>  
> +	ret = kvm_register_device_ops(&kvm_arm_vgic_v2_ops,
> +				       KVM_DEV_TYPE_ARM_VGIC_V2);
> +	if (ret)
> +		goto out_free_irq;
> +

Need call __unregister_cpu_notifier(), since __register_cpu_notifier()
is already successfully called.

Need print some information for failure via kvm_err().

Thanks.
>  	/* Callback into for arch code for setup */
>  	vgic_arch_setup(vgic);
>  
>  	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());
> 
> This achieves the exact same effect.
> 
> Thanks,
> 
> 	M.
> 

-- 
Chen Gang

Open share and attitude like air water and life which God blessed