kvm.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Theodore Ts'o <tytso@mit.edu>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>,
	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
Date: Wed, 13 Aug 2014 10:32:09 -0400	[thread overview]
Message-ID: <20140813143209.GD6437@thunk.org> (raw)
In-Reply-To: <53EB1859.6030800@zytor.com>

On Wed, Aug 13, 2014 at 12:48:41AM -0700, H. Peter Anvin wrote:
> The proposed arch_get_rng_seed() is not really what it claims to be; it
> most definitely does not produce seed-grade randomness, instead it seems
> to be an arch function for best-effort initialization of the entropy
> pools -- which is fine, it is just something quite different.

Without getting into an argument about which definition of "seed" is
correct --- it's certainly confusing and different form the RDSEED
usage of the word "seed".

Do we expect that anyone else besides arch_get_rnd_seed() would
actually want to use it?  I'd argue no; we want the rest of the kernel
to either use get_random_bytes() or prandom_u32().  Given that, maybe
we should just call it arch_random_init(), and expect that the only
user of this interface would be drivers/char/random.c?

					- Ted

  parent reply	other threads:[~2014-08-13 14:32 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-07-24  4:57 [PATCH v5 0/5] random,x86,kvm: Rework arch RNG seeds and get some from kvm Andy Lutomirski
2014-07-24  4:57 ` [PATCH v5 1/5] x86,kvm: Add MSR_KVM_GET_RNG_SEED and a matching feature bit Andy Lutomirski
2014-07-31 11:56   ` Paolo Bonzini
2014-07-24  4:57 ` [PATCH v5 2/5] random: Add and use arch_get_rng_seed Andy Lutomirski
2014-07-29 23:46   ` Andy Lutomirski
2014-08-04 22:25   ` Theodore Ts'o
2014-07-24  4:57 ` [PATCH v5 3/5] x86,random: Add an x86 implementation of arch_get_rng_seed Andy Lutomirski
2014-07-24  4:57 ` [PATCH v5 4/5] x86,random,kvm: Use KVM_GET_RNG_SEED in arch_get_rng_seed Andy Lutomirski
2014-07-31 11:56   ` Paolo Bonzini
2014-07-24  4:57 ` [PATCH v5 5/5] x86,kaslr: Use MSR_KVM_GET_RNG_SEED for KASLR if available Andy Lutomirski
2014-07-31 11:56   ` Paolo Bonzini
2014-08-12 19:11 ` [PATCH v5 0/5] random,x86,kvm: Rework arch RNG seeds and get some from kvm Andy Lutomirski
2014-08-12 19:17   ` Theodore Ts'o
2014-08-12 19:22     ` Andy Lutomirski
2014-08-13  7:48       ` H. Peter Anvin
2014-08-13  8:37         ` Andy Lutomirski
2014-08-13 14:32         ` Theodore Ts'o [this message]
2014-08-13 16:13           ` Andy Lutomirski
2014-08-13 17:45             ` H. Peter Anvin
2014-08-13 18:22               ` Theodore Ts'o
2014-08-13 18:33                 ` Andy Lutomirski
2014-08-13 18:44                   ` H. Peter Anvin
2014-08-14  2:41                     ` H. Peter Anvin
2014-08-14  5:14                       ` Andy Lutomirski
2014-08-17  8:44                   ` Paolo Bonzini

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20140813143209.GD6437@thunk.org \
    --to=tytso@mit.edu \
    --cc=ahonig@google.com \
    --cc=bsd@redhat.com \
    --cc=dborkman@redhat.com \
    --cc=gleb@kernel.org \
    --cc=hpa@zytor.com \
    --cc=keescook@chromium.org \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luto@amacapital.net \
    --cc=pbonzini@redhat.com \
    --cc=raghavendra.kt@linux.vnet.ibm.com \
    --cc=vatsa@linux.vnet.ibm.com \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).