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Date: Tue, 01 Oct 2013 11:58:11 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
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To: Michael Ellerman <michael@ellerman.id.au>
Subject: Re: [PATCH 3/3] KVM: PPC: Book3S: Add support for hwrng found on
 some powernv systems
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Il 01/10/2013 10:34, Michael Ellerman ha scritto:
>> If you really want to have the hypercall, implementing it in QEMU means
>> that you can support it on all systems, in fact even when running
>> without KVM.  
> 
> Sure, I can add a fallback to /dev/hwrng for full emulation.
> 
>> The QEMU command line would be something like "-object
>> rng-random,filename=/dev/random,id=rng0 -device spapr-rng,rng=rng0".
> 
> We can't use /dev/random like that. The PAPR specification, which is
> what we're implementing, implies that H_RANDOM provides data from a
> hardware source.

Then use /dev/hwrng.

I don't have POWER machines, but I still want to be able to test as much
as possible using emulation.

Paolo