DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 4CC33356E6
Subject: Re: [PATCH v2 3/3] KVM: SVM: Add irqchip_split() checks before
 enabling AVIC
To: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>,
        =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= <rkrcmar@redhat.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, joro@8bytes.org
References: <1505230962-86304-1-git-send-email-suravee.suthikulpanit@amd.com>
 <1505230962-86304-4-git-send-email-suravee.suthikulpanit@amd.com>
 <20170914152031.GA23415@flask> <3603043c-964f-d10c-8cc0-fa3476e3bbb5@amd.com>
 <dcbe0fce-3d7a-d519-835f-872bf0e65ed2@amd.com>
From: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <36af3324-dd87-c932-2b23-4b4ba45047e4@redhat.com>
Date: Fri, 15 Sep 2017 23:14:23 +0200
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On 15/09/2017 21:21, Suravee Suthikulpanit wrote:
>>>>
>>>>
>>>>  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.
> 
> Actually, thinking about it again, this would not work either since
> pr_xxx_once() would only print the message once per loading of kvm_amd
> module. However, we would prefer the message to be printed per VM
> initialization. I also tried adding the check and print this message in
> the kvm_x86_ops.vm_init(), but this also does not work since the
> vm_init() function is called before the
> kvm_vm_ioctl_enable_cap(KVM_CAP_SPLIT_IRQCHIP).
> 
> Therefore, pr_info() might be better here, even though this would get
> print per VCPU initialization. Any other suggestions?

My suggestion is to make it pr_info_once.  No one looks at dmesg anyway
unless things go very wrong.

Paolo