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Date:   Wed, 5 Jun 2019 13:20:31 +0100
From:   Will Deacon <will.deacon@arm.com>
To:     Ali Saidi <alisaidi@amazon.com>
Cc:     linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-crypto@vger.kernel.org,
        Catalin Marinas <catalin.marinas@arm.com>,
        Matt Mackall <mpm@selenic.com>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Ron Rindjunsky <ronrindj@amazon.com>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        David Woodhouse <dwmw@amazon.co.uk>
Subject: Re: [PATCH 0/3] Add support for Graviton TRNG
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On Tue, Jun 04, 2019 at 08:30:57PM +0000, Ali Saidi wrote:
> AWS Graviton based systems provide an Arm SMC call in the vendor defined
> hypervisor region to read random numbers from a HW TRNG and return them to the
> guest. 
> 
> We've observed slower guest boot and especially reboot times due to lack of
> entropy and providing access to a TRNG is meant to address this. 

Curious, but why this over something like virtio-rng?

Will