Subject: Re: [PATCH v2 3/3] KVM: SVM: Add irqchip_split() checks before
 enabling AVIC
To: =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= <rkrcmar@redhat.com>
References: <1505230962-86304-1-git-send-email-suravee.suthikulpanit@amd.com>
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 <20170914152031.GA23415@flask>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, pbonzini@redhat.com,
        joro@8bytes.org
From: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
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Date: Thu, 14 Sep 2017 08:23:48 -0700
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Radim,

On 9/14/17 08:20, Radim Krčmář wrote:
>> @@ -1594,6 +1593,12 @@ static int avic_init_vcpu(struct vcpu_svm *svm)
>>  	if (!avic)
>>  		return 0;
>>
>> +	if (!kvm_vcpu_apicv_active(&svm->vcpu)) {
>> +		pr_debug("%s: Disable AVIC due to non-split irqchip.\n",
>> +			      __func__);
> We need to have an extra condition just because of this print ...
> I removed the print altogether when applying -- I thought more about
> that and it was aimed at people who wonder why AVIC was suddenly
> disabled and it's unlikely that they will enable a debug message without
> already knowing the reason,

Make sense. Thanks.

>
> thanks.
>
>> @@ -4388,7 +4393,7 @@ static void svm_set_virtual_x2apic_mode(struct kvm_vcpu *vcpu, bool set)
>>
>>  static bool svm_get_enable_apicv(struct kvm_vcpu *vcpu)
>>  {
> A close contender was pr_info_once() here:
>
> 	if (avic && !irqchip_split(vcpu->kvm))
> 		pr_info_once(...)
>

Looks good.

Thanks,
Suravee