From: Linus Torvalds <torvalds@linux-foundation.org>
To: Joerg Roedel <jroedel@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>,
Meelis Roos <mroos@linux.ee>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
linux-mm <linux-mm@kvack.org>,
Andrea Arcangeli <aarcange@redhat.com>
Subject: Re: 32-bit PTI with THP = userspace corruption
Date: Tue, 11 Sep 2018 08:20:33 -1000 [thread overview]
Message-ID: <CA+55aFzo3b2aChbJ2aOSvKbguYKMG8wv02NS8qzp6w2T5z8WTg@mail.gmail.com> (raw)
In-Reply-To: <20180911114927.gikd3uf3otxn2ekq@suse.de>
On Tue, Sep 11, 2018 at 1:49 AM Joerg Roedel <jroedel@suse.de> wrote:
>
> I had a look into the THP and the HugeTLBfs code, and that is not
> really easy to fix there. As I can see it now, there are a few options
> to fix that, but most of them are ugly:
Just do (4): disable PTI with PAE.
Then we can try to make people perhaps not use !PAE very much, and
warn if you have PAE disabled on a machine that supports it.
As you say, there shouldn't be much of a performance impact from PAE.
There is a more noticeable performance impact from HIGHMEM, not from
HIGHMEM_64G, iirc.
Linus
next prev parent reply other threads:[~2018-09-11 18:20 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-08-30 18:09 Meelis Roos
2018-08-30 20:55 ` Joerg Roedel
2018-08-31 4:12 ` Meelis Roos
2018-08-31 7:07 ` Joerg Roedel
2018-09-08 10:24 ` Thomas Gleixner
2018-09-11 11:49 ` Joerg Roedel
2018-09-11 11:58 ` Meelis Roos
2018-09-11 12:12 ` Joerg Roedel
2018-09-18 13:00 ` Alan Cox
2018-10-21 12:37 ` Pavel Machek
2018-10-22 7:56 ` Joerg Roedel
2018-10-22 18:48 ` Alan Cox
2018-10-23 9:11 ` Not-so-old machines without PAE was " Pavel Machek
2018-10-22 20:56 ` Pavel Machek
2018-09-11 18:20 ` Linus Torvalds [this message]
2018-08-31 7:10 ` Meelis Roos
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=CA+55aFzo3b2aChbJ2aOSvKbguYKMG8wv02NS8qzp6w2T5z8WTg@mail.gmail.com \
--to=torvalds@linux-foundation.org \
--cc=aarcange@redhat.com \
--cc=jroedel@suse.de \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mroos@linux.ee \
--cc=tglx@linutronix.de \
/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