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Date: Wed, 13 Aug 2014 19:41:37 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Andy Lutomirski <luto@amacapital.net>, "Theodore Ts'o" <tytso@mit.edu>,
        kvm list <kvm@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Kees Cook <keescook@chromium.org>, X86 ML <x86@kernel.org>,
        Daniel Borkmann <dborkman@redhat.com>,
        Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>,
        Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>,
        Gleb Natapov <gleb@kernel.org>, Paolo Bonzini <pbonzini@redhat.com>,
        Bandan Das <bsd@redhat.com>, Andrew Honig <ahonig@google.com>
Subject: Re: [PATCH v5 0/5] random,x86,kvm: Rework arch RNG seeds and get
 some from kvm
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On 08/13/2014 11:44 AM, H. Peter Anvin wrote:
> On 08/13/2014 11:33 AM, Andy Lutomirski wrote:
>>
>> As for doing arch_random_init after clone/migration, I think we'll
>> need another KVM extension for that, since, AFAIK, we don't actually
>> get notified that we were cloned or migrated.  That will be
>> nontrivial.  Maybe we can figure that out at KS, too.
>>
> 
> We don't need a reset when migrated (although it might be a good idea
> under some circumstances, i.e. if the pools might somehow have gotten
> exposed) but definitely when cloned.
> 

But yes, we need a notification.  For obvious reasons there is no
suspend event (one can snapshot a running VM) but we need to be notified
upon wakeup, *or* we need to give KVM a way to update the necessary state.

	-hpa