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

From: Chen Gang
Date: Sat Nov 29 2014 - 22:19:19 EST


Hello maintainers:

Is this discussion OK? If necessary, I shall send patch v3 according to
your taste.

Thanks.

On 11/15/14 00:30, Chen Gang wrote:
>
> 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
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