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Date:   Thu, 17 Aug 2023 16:53:27 +0000
In-Reply-To: <d6858d5c-7db6-6e4c-7f07-92ff3340e02b@redhat.com> (message from
 Paolo Bonzini on Thu, 10 Aug 2023 16:03:16 +0200)
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Subject: Re: [RFC PATCH 08/11] KVM: x86: Let moving encryption context be configurable
From:   Ackerley Tng <ackerleytng@google.com>
To:     Paolo Bonzini <pbonzini@redhat.com>
Cc:     seanjc@google.com, tglx@linutronix.de, x86@kernel.org,
        kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
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Paolo Bonzini <pbonzini@redhat.com> writes:

> On 8/8/23 01:01, Ackerley Tng wrote:
>> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
>> index 75d48379d94d..a1a28dd77b94 100644
>> --- a/arch/x86/kvm/x86.c
>> +++ b/arch/x86/kvm/x86.c
>> @@ -6351,7 +6351,14 @@ static int kvm_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd)
>>   	if (r)
>>   		goto out_mark_migration_done;
>>   
>> -	r = static_call(kvm_x86_vm_move_enc_context_from)(kvm, source_kvm);
>> +	/*
>> +	 * Different types of VMs will allow userspace to define if moving
>> +	 * encryption context should be supported.
>> +	 */
>> +	if (kvm->arch.vm_move_enc_ctxt_supported &&
>> +	    kvm_x86_ops.vm_move_enc_context_from) {
>> +		r = static_call(kvm_x86_vm_move_enc_context_from)(kvm, source_kvm);
>> +	}
>
> Rather than "supported" this is more "required".  So  perhaps 
> kvm->arch.use_vm_enc_ctxt_op?
>
> Paolo

Thanks, that is a great suggestion, I'll incorporate this in the next
revision!