public inbox for libc-alpha@sourceware.org
 help / color / mirror / Atom feed
From: Florian Weimer <fweimer@redhat.com>
To: "H.J. Lu" <hjl.tools@gmail.com>
Cc: libc-alpha@sourceware.org
Subject: Re: [PATCH] x86: Set FSGSBASE to active if enabled by kernel
Date: Mon, 13 Mar 2023 14:44:36 +0100	[thread overview]
Message-ID: <87zg8grcjf.fsf@oldenburg.str.redhat.com> (raw)
In-Reply-To: <20230309182603.205394-1-hjl.tools@gmail.com> (H. J. Lu's message of "Thu, 9 Mar 2023 10:26:03 -0800")

* H. J. Lu:

> Linux kernel uses AT_HWCAP2 to indicate if FSGSBASE instructions are
> enabled.  If the HWCAP2_FSGSBASE bit in AT_HWCAP2 is set, FSGSBASE
> instructions can be used in user space.  Define dl_check_hwcap2 to set
> the FSGSBASE feature to active on Linux when the HWCAP2_FSGSBASE bit is
> set.

Could you add a test against /proc/cpuinfo flags?  It should be a
perfect match on current kernels.

Thanks,
Florian


  reply	other threads:[~2023-03-13 13:44 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-09 18:26 H.J. Lu
2023-03-13 13:44 ` Florian Weimer [this message]
2023-03-16  0:42   ` H.J. Lu

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=87zg8grcjf.fsf@oldenburg.str.redhat.com \
    --to=fweimer@redhat.com \
    --cc=hjl.tools@gmail.com \
    --cc=libc-alpha@sourceware.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 read-only IMAP folder(s) and NNTP newsgroup(s).