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Date: Tue, 28 May 2024 15:50:32 -0700
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Subject: Re: [PATCH v2 4/6] KVM: Add arch hooks for enabling/disabling virtualization
From: Sean Christopherson <seanjc@google.com>
To: Kai Huang <kai.huang@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, 
	Chao Gao <chao.gao@intel.com>
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On Thu, May 23, 2024, Kai Huang wrote:
> On 22/05/2024 2:28 pm, Sean Christopherson wrote:
> >   static int __kvm_enable_virtualization(void)
> >   {
> >   	if (__this_cpu_read(hardware_enabled))
> > @@ -5604,6 +5614,8 @@ static int kvm_enable_virtualization(void)
> >   	if (kvm_usage_count++)
> >   		return 0;
> > +	kvm_arch_enable_virtualization();
> > +
> >   	r = cpuhp_setup_state(CPUHP_AP_KVM_ONLINE, "kvm/cpu:online",
> >   			      kvm_online_cpu, kvm_offline_cpu);
> 
> 
> Nit:  is kvm_arch_pre_enable_virtualization() a better name?

Hmm, yes?  I don't have a strong preference either way.  I did consider a more
verbose name, but omitted the "pre" because the hook is called only on the 0=>1
transition of kvm_usage_count, and for some reason that made me think "pre" would
be confusing.

On the other hand, "pre" very clearly communicates that the hook is invoked,
and _needs_ to be invoked (for x86), before KVM enables virtualization.

So I'm leaning towards kvm_arch_pre_enable_virtualization().

Anyone else have an opinion?