All of lore.kernel.org
 help / color / mirror / Atom feed
From: "H. Peter Anvin" <hpa@zytor.com>
To: KY Srinivasan <kys@microsoft.com>,
	Andy Lutomirski <luto@amacapital.net>,
	Linux Virtualization <virtualization@lists.linux-foundation.org>,
	kvm list <kvm@vger.kernel.org>
Cc: Gleb Natapov <gleb@kernel.org>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Theodore Ts'o <tytso@mit.edu>
Subject: Re: Standardizing an MSR or other hypercall to get an RNG seed?
Date: Thu, 18 Sep 2014 07:43:09 -0700	[thread overview]
Message-ID: <541AEF7D.2010007@zytor.com> (raw)
In-Reply-To: <2aa00301e9af4826b5781e01709f81e7@BY2PR0301MB0711.namprd03.prod.outlook.com>

On 09/18/2014 07:40 AM, KY Srinivasan wrote:
>>
>> The main questions are what MSR index to use and how to detect the
>> presence of the MSR.  I've played with two approaches:
>>
>> 1. Use CPUID to detect the presence of this feature.  This is very easy for
>> KVM to implement by using a KVM-specific CPUID feature.  The problem is
>> that this will necessarily be KVM-specific, as the guest must first probe for
>> KVM and then probe for the KVM feature.  I doubt that Hyper-V, for
>> example, wants to claim to be KVM.  If we could standardize a non-
>> hypervisor-specific CPUID feature, then this problem would go away.
> 
> We would prefer a CPUID feature bit to detect this feature.
>  

I guess if we're introducing the concept of pan-OS MSRs we could also
have pan-OS CPUID.  The real issue is to get a single non-conflicting
standard.

	-hpa

  reply	other threads:[~2014-09-18 14:43 UTC|newest]

Thread overview: 84+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-09-18  2:50 Standardizing an MSR or other hypercall to get an RNG seed? Andy Lutomirski
2014-09-18 14:40 ` KY Srinivasan
2014-09-18 14:40 ` KY Srinivasan
2014-09-18 14:43   ` H. Peter Anvin [this message]
2014-09-18 15:38     ` Andy Lutomirski
2014-09-18 15:44       ` Andy Lutomirski
2014-09-18 15:58         ` Paolo Bonzini
2014-09-18 16:36       ` KY Srinivasan
2014-09-18 17:13         ` Nakajima, Jun
2014-09-18 17:17           ` Paolo Bonzini
2014-09-18 17:17           ` Paolo Bonzini
2014-09-18 17:20             ` Jake Oshins
2014-09-18 17:20             ` Jake Oshins
2014-09-18 17:20             ` KY Srinivasan
2014-09-18 17:20             ` KY Srinivasan
2014-09-18 17:42               ` Nakajima, Jun
2014-09-18 18:35                 ` Andy Lutomirski
2014-09-18 18:39                   ` H. Peter Anvin
2014-09-18 18:54                     ` Niels Ferguson
2014-09-18 19:03                       ` Andy Lutomirski
2014-09-18 21:54                         ` David Hepkin
2014-09-19  6:04                           ` Paolo Bonzini
2014-09-18 21:54                         ` David Hepkin
2014-09-18 18:58                   ` Paolo Bonzini
2014-09-18 19:07                     ` Andy Lutomirski
2014-09-18 21:21                       ` Nakajima, Jun
2014-09-18 21:35                         ` Andy Lutomirski
2014-09-18 21:46                       ` David Hepkin
2014-09-18 21:57                         ` H. Peter Anvin
2014-09-18 22:07                           ` Andy Lutomirski
2014-09-19  0:49                             ` Nakajima, Jun
2014-09-19  0:49                             ` Nakajima, Jun
2014-09-19  1:03                               ` Andy Lutomirski
2014-09-19  1:28                                 ` Andy Lutomirski
2014-09-19 16:14                                   ` Nakajima, Jun
2014-09-19 16:22                                     ` Paolo Bonzini
2014-09-19 16:40                                     ` H. Peter Anvin
2014-09-19 17:21                                       ` Andy Lutomirski
2014-09-19 17:36                                         ` H. Peter Anvin
2014-09-19 17:39                                           ` Andy Lutomirski
2014-09-19 22:05                                       ` Theodore Ts'o
2014-09-19 22:06                                         ` Andy Lutomirski
2014-09-19 22:57                                           ` Nakajima, Jun
2014-09-19 22:57                                           ` Theodore Ts'o
2014-09-19 23:12                                             ` Andy Lutomirski
2014-09-19 23:29                                               ` H. Peter Anvin
2014-09-19 23:35                                                 ` Theodore Ts'o
2014-09-19 23:41                                                   ` Andy Lutomirski
2014-09-20  0:06                                                   ` H. Peter Anvin
2014-09-19 23:29                                               ` H. Peter Anvin
2014-09-19  1:28                                 ` Andy Lutomirski
2014-09-18 22:00                         ` Andy Lutomirski
2014-09-18 22:03                           ` H. Peter Anvin
2014-09-19 16:37                           ` Gleb Natapov
2014-09-19 16:40                             ` H. Peter Anvin
2014-09-19 16:53                               ` Gleb Natapov
2014-09-19 17:08                                 ` H. Peter Anvin
2014-09-19 17:15                                   ` Gleb Natapov
2014-09-19 17:18                                     ` H. Peter Anvin
2014-09-19 17:49                                       ` Gleb Natapov
2014-09-19 18:02                                         ` Andy Lutomirski
2014-09-19 18:12                                           ` Gleb Natapov
2014-09-19 18:20                                             ` Andy Lutomirski
2014-09-19 20:53                                               ` Gleb Natapov
2014-09-22  4:11                                               ` Alok Kataria
2014-09-19 17:18                                     ` H. Peter Anvin
2014-09-19 17:21                                 ` Andy Lutomirski
2014-09-19 17:59                                   ` Gleb Natapov
2014-09-19 17:59                                   ` Gleb Natapov
2014-09-18 21:46                       ` David Hepkin
2014-09-18 18:56                 ` Paolo Bonzini
2014-09-18 16:36       ` KY Srinivasan
2014-09-19 18:30 ` Christopher Covington
2014-09-19 18:42   ` Andy Lutomirski
2014-09-19 20:21     ` Nadav Amit
2014-09-19 20:46       ` Andy Lutomirski
2014-09-19 21:46         ` H. Peter Anvin
2014-09-22 13:31           ` Christopher Covington
2014-09-22 14:17             ` H. Peter Anvin
2014-09-22 14:18               ` H. Peter Anvin
2014-09-22 23:01             ` H. Peter Anvin
2014-09-21 12:39         ` Paolo Bonzini
2014-09-19 20:21     ` Nadav Amit
2014-09-22 13:33     ` Christopher Covington

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=541AEF7D.2010007@zytor.com \
    --to=hpa@zytor.com \
    --cc=gleb@kernel.org \
    --cc=kvm@vger.kernel.org \
    --cc=kys@microsoft.com \
    --cc=luto@amacapital.net \
    --cc=pbonzini@redhat.com \
    --cc=tytso@mit.edu \
    --cc=virtualization@lists.linux-foundation.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.