historical-speck.lore.kernel.org archive mirror
 help / color / mirror / Atom feed
From: mark gross <mgross@linux.intel.com>
To: speck@linutronix.de
Subject: [MODERATED] [PATCH 0/2] v3 more sampling fun 0
Date: Wed, 11 Mar 2020 08:39:29 -0700	[thread overview]
Message-ID: <cover.1583941169.git.mgross@linux.intel.com> (raw)

From: mark gross <mgross@linux.intel.com>
Subject: [PATCH 0/2] V3: more sampling funn

This is a significantly reworked version of the mitigation control   I think
I've addressed all the high quality feedback give on the first 2 versions.

This version of the mitigation no longer needs to change the structure of
cpu_vuln_whitelist as it creates a similar "affected_processors" list.

--- 

Special Register Buffer Data Sampling is a sampling type of vulnerability that
leaks data across cores sharing the HW-RNG for vulnerable processors.

This leak is fixed by a microcode update and is enabled by default.

This new microcode serializes processor access during execution of RDRAND or
RDSEED. It ensures that the shared buffer is overwritten before it is released
for reuse.

The mitigation impacts the throughput of the RDRAND and RDSEED instructions and
latency of RT processing running on the socket while executing RDRAND or
RDSEED.  The micro benchmark of calling RDRAND many times shows a slowdown.

This patch set enables kernel command line control of this mitigation and
exports vulnerability and mitigation status.

This patch set includes 2 patches:
The fist patch enables the command line control of the mitigation as well as
the sysfs export of vulnerability status.

The second patch has the Documentation/admin-guide/hw-vuln documentation for the
issue and the control over the mitigation.

The microcode defaults to enabling the mitigation.


mark gross (2):
  x86/speculation: Special Register Buffer Data Sampling (SRBDS)
    mitigation control.
  x86/speculation: SRBDS vulnerability and mitigation documentation

 Documentation/admin-guide/hw-vuln/index.rst   |   2 +
 .../special-register-buffer-data-sampling.rst | 145 ++++++++++++++++++
 .../admin-guide/kernel-parameters.txt         |  11 ++
 arch/x86/include/asm/cpu_device_id.h          |  12 ++
 arch/x86/include/asm/cpufeatures.h            |   2 +
 arch/x86/include/asm/msr-index.h              |   4 +
 arch/x86/kernel/cpu/bugs.c                    | 110 +++++++++++++
 arch/x86/kernel/cpu/common.c                  |  41 +++++
 arch/x86/kernel/cpu/cpu.h                     |  13 ++
 arch/x86/kernel/cpu/intel.c                   |   2 +
 arch/x86/kernel/cpu/match.c                   |  26 ++++
 drivers/base/cpu.c                            |   8 +
 12 files changed, 376 insertions(+)
 create mode 100644 Documentation/admin-guide/hw-vuln/special-register-buffer-data-sampling.rst

-- 
2.17.1

             reply	other threads:[~2020-03-11 16:02 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-11 15:39 mark gross [this message]
2020-01-16 22:16 ` [MODERATED] [PATCH 1/2] v3 more sampling fun 1 mark gross
2020-01-30 19:12 ` [MODERATED] [PATCH 2/2] v3 more sampling fun 2 mark gross
     [not found] ` <5e690bea.1c69fb81.16d6d.4b78SMTPIN_ADDED_BROKEN@mx.google.com>
2020-03-11 17:21   ` [MODERATED] Re: [PATCH 1/2] v3 more sampling fun 1 Greg KH
2020-03-11 23:09     ` mark gross
2020-03-11 20:02 ` Thomas Gleixner
2020-03-17 18:56   ` [MODERATED] " mark gross
2020-03-11 20:26 ` [PATCH 2/2] v3 more sampling fun 2 Thomas Gleixner
2020-03-11 20:38   ` [MODERATED] " Andrew Cooper
2020-03-11 23:23   ` mark gross
2020-03-12 22:04   ` mark gross
2020-03-13 15:21     ` Thomas Gleixner
2020-03-11 20:28 ` [MODERATED] Re: [PATCH 1/2] v3 more sampling fun 1 Andrew Cooper
2020-03-11 23:18   ` mark gross
2020-03-12  0:25     ` Luck, Tony
2020-03-12  1:34       ` Andrew Cooper
2020-03-12 15:25         ` Luck, Tony
2020-03-12 16:02           ` Luck, Tony
2020-03-12 16:45             ` Andrew Cooper

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=cover.1583941169.git.mgross@linux.intel.com \
    --to=mgross@linux.intel.com \
    --cc=speck@linutronix.de \
    --subject='Re: [MODERATED] [PATCH 0/2] v3 more sampling fun 0' \
    /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

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).