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Subject: Re: [PATCH] KEYS: asym_tpm: Switch to get_random_bytes()
From:   Mimi Zohar <zohar@linux.ibm.com>
To:     Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
        linux-integrity@vger.kernel.org
Cc:     stable@vger.kernel.org, David Howells <dhowells@redhat.com>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        "David S. Miller" <davem@davemloft.net>,
        "open list:ASYMMETRIC KEYS" <keyrings@vger.kernel.org>,
        "open list:CRYPTO API" <linux-crypto@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>
Date:   Wed, 02 Oct 2019 10:00:19 -0400
In-Reply-To: <20190926171601.30404-1-jarkko.sakkinen@linux.intel.com>
References: <20190926171601.30404-1-jarkko.sakkinen@linux.intel.com>
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On Thu, 2019-09-26 at 20:16 +0300, Jarkko Sakkinen wrote:
> Only the kernel random pool should be used for generating random numbers.
> TPM contributes to that pool among the other sources of entropy. In here it
> is not, agreed, absolutely critical because TPM is what is trusted anyway
> but in order to remove tpm_get_random() we need to first remove all the
> call sites.

At what point during boot is the kernel random pool available?  Does
this imply that you're planning on changing trusted keys as well?

Mimi