All of lore.kernel.org
 help / color / mirror / Atom feed
From: Thomas Gleixner <tglx@linutronix.de>
To: speck@linutronix.de
Subject: Re: [PATCH v5 08/11] TAAv5 8
Date: Mon, 21 Oct 2019 10:09:41 +0200 (CEST)	[thread overview]
Message-ID: <alpine.DEB.2.21.1910211002450.1904@nanos.tec.linutronix.de> (raw)
In-Reply-To: <20191018001407.GA28905@guptapadev.amr>

On Thu, 17 Oct 2019, speck for Pawan Gupta wrote:
> On Wed, Oct 16, 2019 at 02:15:08PM +0200, speck for Thomas Gleixner wrote:
> Below is the matrix for the impact of tsx=<on|off|auto> cmdline options
> on state of TAA mitigation, VERW behavior and TSX feature for various
> combinations of MSR_IA32_ARCH_CAPABILITIES bits.
> 
> 1. tsx=auto
> +----------+----------+----------------+---------------+--------------+-------------------+
> |  MSR_IA32_ARCH_CAPABILITIES bits     |           Result with cmdline tsx=auto           |
> +----------+----------+----------------+---------------+--------------+-------------------+
> |  TAA_NO  |  MDS_NO  |  TSX_CTRL_MSR  |  VERW clears  |  TSX state   |  TAA mitigation   |
> |          |          |                |  CPU buffers  | after bootup |                   |
> +==========+==========+================+===============+==============+===================+
> |    0     |    0     |       0        |      Yes      |  HW default  |    Same as MDS    |
> +----------+----------+----------------+---------------+--------------+-------------------+
> |    0     |    0     |       1        | Invalid case  | Invalid case |   Invalid case    |
> +----------+----------+----------------+---------------+--------------+-------------------+

So you're saying that if TSX_CTRL_MSR is available VERW clears CPU buffers
independent of MDS_NO being set, right? So:

  MDS_NO	MD_CLEAR	TSX_CTRL_MSR
    0		  0		    0		Vulnerable (needs ucode)
    0		  1		    0		MDS and TAA mitigated via VERW
    1		  1		    0		MDS fixed, TAA vulnerable if TSX enabled
    		  		    		because MD_CLEAR has no meaning and
						VERW is not guaranteed to clear buffers
    1		  x		    1		MDS fixed, TAA can be mitigated by
    		  		    		    	   VERW or TSX_CTRL_MSR

If so, please document all of that proper and fixup the other comments
people had on this series.

Thanks,

	tglx

  reply	other threads:[~2019-10-21  8:09 UTC|newest]

Thread overview: 75+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-05  6:17 [MODERATED] [PATCH v5 00/11] TAAv5 0 Pawan Gupta
2019-10-05  6:26 ` [MODERATED] [PATCH v5 01/11] TAAv5 1 Pawan Gupta
2019-10-05  6:27 ` [MODERATED] [PATCH v5 02/11] TAAv5 2 Pawan Gupta
2019-10-05  6:28 ` [MODERATED] [PATCH v5 03/11] TAAv5 3 Pawan Gupta
2019-10-05  6:29 ` [MODERATED] [PATCH v5 04/11] TAAv5 4 Pawan Gupta
2019-10-05  6:30 ` [MODERATED] [PATCH v5 05/11] TAAv5 5 Pawan Gupta
2019-10-05  6:31 ` [MODERATED] [PATCH v5 06/11] TAAv5 6 Pawan Gupta
2019-10-05  6:32 ` [MODERATED] [PATCH v5 07/11] TAAv5 7 Pawan Gupta
2019-10-05  6:33 ` [MODERATED] [PATCH v5 08/11] TAAv5 8 Pawan Gupta
2019-10-05  6:34 ` [MODERATED] [PATCH v5 09/11] TAAv5 9 Pawan Gupta
2019-10-05  6:35 ` [MODERATED] [PATCH v5 10/11] TAAv5 10 Pawan Gupta
2019-10-05  6:36 ` [MODERATED] [PATCH v5 11/11] TAAv5 11 Pawan Gupta
2019-10-05 10:54 ` [MODERATED] Re: [PATCH v5 02/11] TAAv5 2 Borislav Petkov
2019-10-07 17:48   ` Pawan Gupta
     [not found] ` <5d98396a.1c69fb81.6c7a8.23b1SMTPIN_ADDED_BROKEN@mx.google.com>
2019-10-05 21:43   ` [MODERATED] Re: [PATCH v5 03/11] TAAv5 3 Andy Lutomirski
2019-10-07 17:50     ` Pawan Gupta
     [not found] ` <5d9839a4.1c69fb81.238e9.8312SMTPIN_ADDED_BROKEN@mx.google.com>
2019-10-05 21:45   ` [MODERATED] Re: [PATCH v5 04/11] TAAv5 4 Andy Lutomirski
     [not found] ` <5d983ad2.1c69fb81.63edd.6575SMTPIN_ADDED_BROKEN@mx.google.com>
2019-10-05 21:49   ` [MODERATED] Re: [PATCH v5 09/11] TAAv5 9 Andy Lutomirski
2019-10-07 18:35     ` Pawan Gupta
     [not found] ` <5d9838f1.1c69fb81.f1bab.d886SMTPIN_ADDED_BROKEN@mx.google.com>
2019-10-05 21:49   ` [MODERATED] Re: [PATCH v5 01/11] TAAv5 1 Andy Lutomirski
2019-10-06 17:40     ` Andrew Cooper
     [not found] ` <5d983ad2.1c69fb81.e6640.8f51SMTPIN_ADDED_BROKEN@mx.google.com>
2019-10-06 17:06   ` [MODERATED] Re: [PATCH v5 09/11] TAAv5 9 Greg KH
2019-10-08  6:01     ` Pawan Gupta
2019-10-10 21:31       ` Pawan Gupta
2019-10-11  8:45         ` Greg KH
2019-10-21  8:00           ` Thomas Gleixner
2019-10-08  2:46 ` [MODERATED] Re: [PATCH v5 05/11] TAAv5 5 Josh Poimboeuf
2019-10-09  1:45   ` Pawan Gupta
2019-10-08  2:57 ` [MODERATED] Re: [PATCH v5 09/11] TAAv5 9 Josh Poimboeuf
2019-10-08  6:10   ` Pawan Gupta
2019-10-08 10:49     ` Jiri Kosina
2019-10-09 13:12 ` [MODERATED] Re: ***UNCHECKED*** [PATCH v5 08/11] TAAv5 8 Michal Hocko
2019-10-14 19:41   ` Thomas Gleixner
2019-10-14 19:51     ` [MODERATED] " Jiri Kosina
2019-10-14 21:04       ` [MODERATED] " Borislav Petkov
2019-10-14 21:31         ` Jiri Kosina
2019-10-15  8:01           ` Thomas Gleixner
2019-10-15 10:34             ` [MODERATED] Re: ***UNCHECKED*** " Michal Hocko
2019-10-15 13:06               ` Josh Poimboeuf
2019-10-15 13:10                 ` Jiri Kosina
2019-10-15 15:26                   ` Josh Poimboeuf
2019-10-15 15:32                     ` Jiri Kosina
2019-10-15 19:34                       ` Tyler Hicks
2019-10-15 20:00                       ` Josh Poimboeuf
2019-10-15 20:15                         ` Jiri Kosina
2019-10-15 20:35                           ` Jiri Kosina
2019-10-15 20:54                             ` Josh Poimboeuf
2019-10-15 20:56                             ` [MODERATED] " Pawan Gupta
2019-10-15 21:14                               ` Jiri Kosina
2019-10-15 23:12                                 ` Josh Poimboeuf
2019-10-15 23:13                                   ` [MODERATED] [AUTOREPLY] [MODERATED] [AUTOREPLY] Automatic reply: " James, Hengameh M
2019-10-16  4:52                                   ` [MODERATED] " Jiri Kosina
2019-10-16  5:05                                     ` Jiri Kosina
2019-10-21 21:15                                       ` Luck, Tony
2019-10-16  7:14                                     ` Josh Poimboeuf
2019-10-16  7:20                                       ` Jiri Kosina
2019-10-18  1:17                                   ` Ben Hutchings
2019-10-18  4:04                                     ` Pawan Gupta
2019-10-15 17:47               ` Borislav Petkov
2019-10-16  7:26               ` [MODERATED] Re: ***UNCHECKED*** " Jiri Kosina
2019-10-16  7:54                 ` [MODERATED] Re: ***UNCHECKED*** " Michal Hocko
2019-10-16  9:23                   ` [MODERATED] Re: ***UNCHECKED*** " Michal Hocko
2019-10-16 12:15                     ` Thomas Gleixner
2019-10-16 18:34                       ` [MODERATED] " Pawan Gupta
2019-10-18  0:14                       ` Pawan Gupta
2019-10-21  8:09                         ` Thomas Gleixner [this message]
2019-10-21 12:54                         ` [MODERATED] Re: ***UNCHECKED*** " Michal Hocko
2019-10-21 20:01                           ` [MODERATED] " Pawan Gupta
2019-10-21 20:33                             ` Josh Poimboeuf
2019-10-21 20:34                               ` Josh Poimboeuf
2019-10-21 20:33                                 ` Pawan Gupta
2019-10-21 23:01                                   ` Andrew Cooper
2019-10-21 23:37                                     ` Luck, Tony
2019-10-21 23:39                                       ` Andrew Cooper
2019-10-14 21:05       ` [MODERATED] Re: ***UNCHECKED*** " Michal Hocko

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=alpine.DEB.2.21.1910211002450.1904@nanos.tec.linutronix.de \
    --to=tglx@linutronix.de \
    --cc=speck@linutronix.de \
    /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.