From: Pavel Machek <pavel@ucw.cz>
To: Jiri Kosina <jikos@kernel.org>
Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk>,
Linus Torvalds <torvalds@linux-foundation.org>,
Dan Williams <dan.j.williams@intel.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Mark Rutland <mark.rutland@arm.com>,
linux-arch@vger.kernel.org, Peter Zijlstra <peterz@infradead.org>,
Greg KH <gregkh@linuxfoundation.org>,
Thomas Gleixner <tglx@linutronix.de>,
Elena Reshetova <elena.reshetova@intel.com>
Subject: Re: [RFC PATCH] asm/generic: introduce if_nospec and nospec_barrier
Date: Thu, 4 Jan 2018 20:39:36 +0100 [thread overview]
Message-ID: <20180104193936.GB10427@amd> (raw)
In-Reply-To: <nycvar.YFH.7.76.1801040243300.11852@cbobk.fhfr.pm>
[-- Attachment #1: Type: text/plain, Size: 882 bytes --]
On Thu 2018-01-04 02:47:51, Jiri Kosina wrote:
> On Thu, 4 Jan 2018, Alan Cox wrote:
>
> > > If the CPU speculation can cause these kinds of side-effects, it just must
> > > not happen, full stop.
> >
> > At which point your performance will resemble that of a 2012 atom
> > processor at best.
>
> You know what? I'd be completely fine with that, if it's traded for "my
> ssh and internet banking keys are JUST MINE, ok?" :)
Agreed.
For kernel, we may be able to annonate "tainted" pointers. But then
there's quite a lot of code in userspace... What will need to be
modified? Just JITs? Setuid programs?
And we can get part of the performance back by adding more of
SMT... AFAICT.
Best regards,
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 181 bytes --]
next prev parent reply other threads:[~2018-01-04 19:39 UTC|newest]
Thread overview: 82+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-01-03 22:38 [RFC PATCH 0/4] API for inhibiting speculative arbitrary read primitives Mark Rutland
2018-01-03 22:38 ` [RFC PATCH 1/4] asm-generic/barrier: add generic nospec helpers Mark Rutland
2018-01-03 22:38 ` Mark Rutland
2018-01-04 12:00 ` Mark Rutland
2018-01-05 4:21 ` Dan Williams
2018-01-05 9:15 ` Mark Rutland
2018-01-03 22:38 ` [RFC PATCH 2/4] Documentation: document " Mark Rutland
2018-01-03 22:38 ` Mark Rutland
2018-01-03 22:38 ` [RFC PATCH 3/4] arm64: implement nospec_{load,ptr}() Mark Rutland
2018-01-03 22:38 ` Mark Rutland
2018-01-03 22:38 ` [RFC PATCH 4/4] bpf: inhibit speculated out-of-bounds pointers Mark Rutland
2018-01-03 22:38 ` Mark Rutland
2018-01-03 23:45 ` Peter Zijlstra
2018-01-03 23:45 ` Peter Zijlstra
2018-01-04 10:59 ` Mark Rutland
2018-01-04 0:15 ` [RFC PATCH] asm/generic: introduce if_nospec and nospec_barrier Dan Williams
2018-01-04 0:15 ` Dan Williams
2018-01-04 0:39 ` Linus Torvalds
2018-01-04 1:07 ` Alan Cox
2018-01-04 1:13 ` Dan Williams
2018-01-04 1:13 ` Dan Williams
2018-01-04 6:28 ` Julia Lawall
2018-01-04 17:58 ` Dan Williams
2018-01-04 19:26 ` Pavel Machek
2018-01-04 19:26 ` Pavel Machek
2018-01-04 21:43 ` Dan Williams
2018-01-04 22:20 ` Linus Torvalds
2018-01-04 22:23 ` Linus Torvalds
2018-01-04 22:55 ` Alan Cox
2018-01-04 23:06 ` Linus Torvalds
2018-01-04 23:11 ` Alan Cox
2018-01-04 23:11 ` Alan Cox
2018-01-05 0:24 ` Dan Williams
2018-01-04 22:44 ` Pavel Machek
2018-01-04 23:12 ` Dan Williams
2018-01-04 23:12 ` Dan Williams
2018-01-04 23:21 ` Alan Cox
2018-01-04 23:33 ` Pavel Machek
2018-01-05 8:11 ` Julia Lawall
2018-01-04 1:27 ` Jiri Kosina
2018-01-04 1:27 ` Jiri Kosina
2018-01-04 1:41 ` Alan Cox
2018-01-04 1:47 ` Jiri Kosina
2018-01-04 1:47 ` Jiri Kosina
2018-01-04 19:39 ` Pavel Machek [this message]
2018-01-04 20:32 ` Alan Cox
2018-01-04 20:32 ` Alan Cox
2018-01-04 20:39 ` Jiri Kosina
2018-01-04 21:23 ` Alan Cox
2018-01-04 21:23 ` Alan Cox
2018-01-04 21:48 ` Pavel Machek
2018-01-04 1:51 ` Dan Williams
2018-01-04 1:51 ` Dan Williams
2018-01-04 1:54 ` Linus Torvalds
2018-01-04 1:54 ` Linus Torvalds
2018-01-04 3:10 ` Williams, Dan J
2018-01-04 4:44 ` Al Viro
2018-01-04 5:44 ` Dan Williams
2018-01-04 5:49 ` Dave Hansen
2018-01-04 5:49 ` Dave Hansen
2018-01-04 5:50 ` Al Viro
2018-01-04 5:55 ` Al Viro
2018-01-04 6:42 ` Dan Williams
2018-01-04 5:01 ` Eric W. Biederman
2018-01-04 6:32 ` Dan Williams
2018-01-04 14:54 ` Eric W. Biederman
2018-01-04 16:39 ` Mark Rutland
2018-01-04 20:56 ` Pavel Machek
2018-01-04 20:56 ` Pavel Machek
2018-01-04 11:47 ` Mark Rutland
2018-01-04 11:47 ` Mark Rutland
2018-01-04 22:09 ` Dan Williams
2018-01-05 14:40 ` Mark Rutland
2018-01-05 16:44 ` Dan Williams
2018-01-05 18:05 ` Dan Williams
2018-01-04 1:59 ` Jiri Kosina
2018-01-04 1:59 ` Jiri Kosina
2018-01-04 2:15 ` Alan Cox
2018-01-04 3:12 ` Alexei Starovoitov
2018-01-04 9:16 ` Reshetova, Elena
2018-01-04 9:16 ` Reshetova, Elena
2018-01-04 20:40 ` Pavel Machek
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=20180104193936.GB10427@amd \
--to=pavel@ucw.cz \
--cc=dan.j.williams@intel.com \
--cc=elena.reshetova@intel.com \
--cc=gnomes@lxorguk.ukuu.org.uk \
--cc=gregkh@linuxfoundation.org \
--cc=jikos@kernel.org \
--cc=linux-arch@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=peterz@infradead.org \
--cc=tglx@linutronix.de \
--cc=torvalds@linux-foundation.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).