From: Linus Torvalds <torvalds@linux-foundation.org>
To: Borislav Petkov <bp@suse.de>
Cc: Rik van Riel <riel@surriel.com>,
Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
x86-ml <x86@kernel.org>, lkml <linux-kernel@vger.kernel.org>
Subject: Re: [GIT PULL] x86 FPU changes for 5.2
Date: Tue, 7 May 2019 10:35:25 -0700 [thread overview]
Message-ID: <CAHk-=wh4Cjb1qDj_VRW9W4d4n9WLksgMKF-roG8eCk_O0ZaEEg@mail.gmail.com> (raw)
In-Reply-To: <20190507132632.GB26655@zn.tnic>
On Tue, May 7, 2019 at 6:26 AM Borislav Petkov <bp@suse.de> wrote:
>
> This branch contains work started by Rik van Riel and brought to
> fruition by Sebastian Andrzej Siewior with the main goal to optimize
> when to load FPU registers: only when returning to userspace and not on
> every context switch (while the task remains in the kernel).
I love this and we should have done it long ago, but I also worry that
every time we've messed with the FP state, we've had interesting bugs.
Which is obviously why we didn't do this long ago.
Has this gone through lots of testing, particularly with things like
FP signal handling and old machines that don't necessarily have
anything but the most basic FP state (ie Pentium class etc)?
I've pulled it, but I'd still like to feel safer about it after-the-fact ;)
Linus
next prev parent reply other threads:[~2019-05-07 17:35 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-07 13:26 [GIT PULL] x86 FPU changes for 5.2 Borislav Petkov
2019-05-07 17:35 ` Linus Torvalds [this message]
2019-05-07 17:59 ` Borislav Petkov
2019-05-07 20:12 ` Ingo Molnar
2019-05-07 21:59 ` Sebastian Andrzej Siewior
2019-05-07 17:55 ` pr-tracker-bot
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='CAHk-=wh4Cjb1qDj_VRW9W4d4n9WLksgMKF-roG8eCk_O0ZaEEg@mail.gmail.com' \
--to=torvalds@linux-foundation.org \
--cc=bigeasy@linutronix.de \
--cc=bp@suse.de \
--cc=linux-kernel@vger.kernel.org \
--cc=riel@surriel.com \
--cc=x86@kernel.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).