archive mirror
 help / color / mirror / Atom feed
From: Andy Lutomirski <>
To: LKML <>, X86 ML <>,
	Stas Sergeev <>
Subject: Linux FSGSBASE testing
Date: Sat, 20 Jun 2020 08:59:57 -0700	[thread overview]
Message-ID: <> (raw)

Hi Stas-

FSGSBASE support is queued up for Linux 5.9.  Since you're one of the
more exotic users of segmentation on Linux, is there any chance you
could test it?  The code is here:

There are two interesting cases to test:

1. FSGSBASE on.  This is the default if you boot this kernel on Ivy
Bridge or newer hardware.

2. FSGSBASE off on a patched kernel.  Boot the same kernel as in #1
but either pass nofsgsbase on the kernel command line or use pre-Ivy
Bridge hardware.  You will *

You can tell you have FSGSBASE enabled for test #1 by running
tools/testing/selftests/x86/fsgsbase_64 -- the first line of output
will be :FSGSBASE instructions are enabled".  You can build it by
cd-ing to tools/testing/selftests/x86 and running make.

If anything is broken for you, I'd like to know before this makes it
into a released kernel!


             reply	other threads:[~2020-06-20 16:00 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-20 15:59 Andy Lutomirski [this message]
2020-06-20 16:20 ` Andy Lutomirski
2020-07-18 20:18 ` Don Porter

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:

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

  git send-email \ \ \ \ \ \
    --subject='Re: Linux FSGSBASE testing' \

* 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).