linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: linux@armlinux.org.uk (Russell King - ARM Linux)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 0/5] Spectre big.Little updates
Date: Wed, 19 Sep 2018 10:48:02 +0100	[thread overview]
Message-ID: <20180919094802.GH30658@n2100.armlinux.org.uk> (raw)

This series of patches allows Spectre to be worked around on
big.Little systems, and as far as I'm aware, completes the Spectre
workarounds as were known at the beginning of the year for 32-bit
ARM.

In order to solve Spectre for such systems, we need to introduce
per-CPU indirection of the "processor" vtable, but we are unable to
use the kernel's per-CPU infrastructure as this is not initialised
early enough.

To work around that, we fall back to using a static array of
processor vtables indexed by the logical CPU number.  This should
not be a problem as 32-bit ARM systems are limited to 8 logical
CPUs.

 arch/arm/include/asm/cputype.h  |  2 ++
 arch/arm/include/asm/proc-fns.h | 49 ++++++++++++++++++++++++++++++++---------
 arch/arm/kernel/bugs.c          |  4 ++--
 arch/arm/kernel/head-common.S   |  6 ++---
 arch/arm/kernel/setup.c         | 40 ++++++++++++++++++++-------------
 arch/arm/kernel/smp.c           | 31 ++++++++++++++++++++++++++
 arch/arm/mm/proc-v7-bugs.c      | 17 ++------------
 7 files changed, 103 insertions(+), 46 deletions(-)

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 13.8Mbps down 630kbps up
According to speedtest.net: 13Mbps down 490kbps up

             reply	other threads:[~2018-09-19  9:48 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-09-19  9:48 Russell King - ARM Linux [this message]
2018-09-19  9:48 ` [PATCH 1/5] ARM: make lookup_processor_type() non-__init Russell King
2018-09-20  9:07   ` Julien Thierry
2018-09-19  9:48 ` [PATCH 2/5] ARM: split out processor lookup Russell King
2018-09-20  9:05   ` Julien Thierry
2018-09-19  9:49 ` [PATCH 3/5] ARM: clean up per-processor check_bugs method call Russell King
2018-09-20  9:06   ` Julien Thierry
2018-09-19  9:49 ` [PATCH 4/5] ARM: add PROC_VTABLE macro Russell King
2018-09-20  9:07   ` Julien Thierry
2018-09-19  9:49 ` [PATCH 5/5] ARM: spectre-v2: per-CPU vtables to work around big.Little systems Russell King
2018-09-20  9:04   ` Julien Thierry
2018-09-20  9:21     ` Russell King - ARM Linux
2018-09-20  9:28       ` Julien Thierry
2018-10-05  9:09   ` Marek Szyprowski
2018-10-05  9:35     ` Krzysztof Kozlowski
2018-10-05  9:46     ` Russell King - ARM Linux
2018-10-30 10:50       ` Russell King - ARM Linux
2018-10-31 15:21         ` Marek Szyprowski
2018-10-31 18:12           ` Russell King - ARM Linux
2018-11-02 17:17         ` Kevin Hilman

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=20180919094802.GH30658@n2100.armlinux.org.uk \
    --to=linux@armlinux.org.uk \
    --cc=linux-arm-kernel@lists.infradead.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).