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Message-ID: <2d873eb4-67d2-446d-8208-a43a4a8aba14@intel.com>
Date: Thu, 23 May 2024 10:33:17 +1200
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH v2 4/6] KVM: Add arch hooks for enabling/disabling
 virtualization
To: Sean Christopherson <seanjc@google.com>, Paolo Bonzini
	<pbonzini@redhat.com>
CC: <kvm@vger.kernel.org>, <linux-kernel@vger.kernel.org>, Chao Gao
	<chao.gao@intel.com>
References: <20240522022827.1690416-1-seanjc@google.com>
 <20240522022827.1690416-5-seanjc@google.com>
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From: "Huang, Kai" <kai.huang@intel.com>
In-Reply-To: <20240522022827.1690416-5-seanjc@google.com>
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On 22/05/2024 2:28 pm, Sean Christopherson wrote:
> Add arch hooks that are invoked when KVM enables/disable virtualization.
> x86 will use the hooks to register an "emergency disable" callback, which
> is essentially an x86-specific shutdown notifier that is used when the
> kernel is doing an emergency reboot/shutdown/kexec.
> 
> Signed-off-by: Sean Christopherson <seanjc@google.com>

Reviewed-by: Kai Huang <kai.huang@intel.com>

[...]

> +
>   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?