All of lore.kernel.org
 help / color / mirror / Atom feed
From: Willy Tarreau <w@1wt.eu>
To: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>,
	Alexei Starovoitov <alexei.starovoitov@gmail.com>,
	Andy Lutomirski <luto@kernel.org>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Peter Zijlstra <peterz@infradead.org>,
	LKML <linux-kernel@vger.kernel.org>, X86 ML <x86@kernel.org>,
	Borislav Petkov <bp@alien8.de>, Brian Gerst <brgerst@gmail.com>,
	Ingo Molnar <mingo@kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Kees Cook <keescook@chromium.org>
Subject: Re: [RFC PATCH v2 6/6] x86/entry/pti: don't switch PGD on when pti_disable is set
Date: Thu, 11 Jan 2018 20:11:30 +0100	[thread overview]
Message-ID: <20180111191130.GH15344@1wt.eu> (raw)
In-Reply-To: <a8b043b5-84a9-af92-ffcc-4b9c68f6917d@linux.intel.com>

On Thu, Jan 11, 2018 at 10:38:07AM -0800, Dave Hansen wrote:
> On 01/11/2018 10:32 AM, Josh Poimboeuf wrote:
> >> hmm. Exposing cr3 to user space will make it trivial for user process
> >> to know whether kpti is active. Not sure how exploitable such
> >> information leak.
> > It's already trivial to detect PTI from user space.
> 
> Do tell.

Probably because meltdown doesn't work anymore ? :-)

Willy

  parent reply	other threads:[~2018-01-11 19:12 UTC|newest]

Thread overview: 104+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-01-09 12:56 [RFC PATCH v2 0/6] Per process PTI activation Willy Tarreau
2018-01-09 12:56 ` [RFC PATCH v2 1/6] x86/mm: add a pti_disable entry in mm_context_t Willy Tarreau
2018-01-09 12:56 ` [RFC PATCH v2 2/6] x86/arch_prctl: add ARCH_GET_NOPTI and ARCH_SET_NOPTI to enable/disable PTI Willy Tarreau
2018-01-09 14:17   ` Borislav Petkov
2018-01-09 14:36     ` Willy Tarreau
2018-01-09 14:51       ` Borislav Petkov
2018-01-09 14:54         ` Willy Tarreau
2018-01-09 21:26           ` Andy Lutomirski
2018-01-09 21:29             ` Borislav Petkov
2018-01-09 21:32               ` Willy Tarreau
2018-01-09 21:46                 ` Borislav Petkov
2018-01-09 22:06                   ` Willy Tarreau
2018-01-09 22:20                     ` Borislav Petkov
2018-01-09 22:29                       ` Dave Hansen
2018-01-09 22:40                       ` Willy Tarreau
2018-01-10 14:42                         ` Borislav Petkov
2018-01-10 15:39                           ` Willy Tarreau
2018-01-10 16:09                             ` Borislav Petkov
2018-01-10 16:19                               ` Willy Tarreau
2018-01-10 17:28                                 ` Borislav Petkov
2018-01-10  7:31                       ` Ingo Molnar
2018-01-10  7:37                         ` Willy Tarreau
2018-01-10  7:59                           ` Ingo Molnar
2018-01-09 23:53                     ` Andy Lutomirski
2018-01-10  4:25                       ` Willy Tarreau
2018-01-10  7:25               ` Ingo Molnar
2018-01-10 14:45                 ` Borislav Petkov
2018-01-10 15:43                   ` Willy Tarreau
2018-01-10 15:45                   ` Ingo Molnar
2018-01-09 21:34             ` Kees Cook
2018-01-09 21:41             ` Willy Tarreau
2018-01-09 21:50               ` Kees Cook
2018-01-09 22:03                 ` Willy Tarreau
2018-01-10  7:13             ` Ingo Molnar
2018-01-12 15:03   ` David Laight
2018-01-12 15:06     ` Willy Tarreau
2018-01-09 12:56 ` [RFC PATCH v2 3/6] x86/pti: add a per-cpu variable pti_disable Willy Tarreau
2018-01-10  7:19   ` Ingo Molnar
2018-01-10  7:29     ` Willy Tarreau
2018-01-10  8:01       ` Ingo Molnar
2018-01-10  8:50         ` Willy Tarreau
2018-01-10  8:59           ` Ingo Molnar
2018-01-10  9:00             ` Willy Tarreau
2018-01-09 12:56 ` [RFC PATCH v2 4/6] x86/pti: don't mark the user PGD with _PAGE_NX Willy Tarreau
2018-01-09 12:56 ` [RFC PATCH v2 5/6] x86/entry/pti: avoid setting CR3 when it's already correct Willy Tarreau
2018-01-10  7:16   ` Ingo Molnar
2018-01-10  7:18     ` Willy Tarreau
2018-01-10 20:29   ` Dave Hansen
2018-01-11  6:46     ` Willy Tarreau
2018-01-09 12:56 ` [RFC PATCH v2 6/6] x86/entry/pti: don't switch PGD on when pti_disable is set Willy Tarreau
2018-01-10  7:15   ` Ingo Molnar
2018-01-10  7:23     ` Willy Tarreau
2018-01-10  8:22   ` Peter Zijlstra
2018-01-10  9:11     ` Willy Tarreau
2018-01-10 19:21       ` Andy Lutomirski
2018-01-10 19:39         ` Willy Tarreau
2018-01-10 19:44           ` Andy Lutomirski
2018-01-10 19:50         ` Linus Torvalds
2018-01-10 20:04           ` Andy Lutomirski
2018-01-11  6:42           ` Willy Tarreau
2018-01-11 15:29             ` Dave Hansen
2018-01-11 15:44               ` Willy Tarreau
2018-01-11 15:51                 ` Dave Hansen
2018-01-11 17:02                   ` Andy Lutomirski
2018-01-11 18:21                     ` Alexei Starovoitov
2018-01-11 18:30                       ` Dave Hansen
2018-01-11 18:32                       ` Josh Poimboeuf
2018-01-11 18:36                         ` Linus Torvalds
2018-01-11 18:38                         ` Dave Hansen
2018-01-11 18:51                           ` Linus Torvalds
2018-01-11 18:57                             ` Dave Hansen
2018-01-11 19:05                               ` Josh Poimboeuf
2018-01-11 19:07                               ` Borislav Petkov
2018-01-11 19:17                                 ` Dave Hansen
2018-01-11 19:19                                   ` Olivier Galibert
2018-01-11 19:26                                     ` Josh Poimboeuf
2018-01-11 19:34                                       ` Alan Cox
2018-01-11 21:23                                         ` Willy Tarreau
2018-01-11 21:28                                           ` Linus Torvalds
2018-01-11 22:06                                             ` Willy Tarreau
2018-01-12 16:37                                               ` David Laight
2018-01-11 19:12                               ` Linus Torvalds
2018-01-11 19:38                               ` Alexei Starovoitov
2018-01-11 19:11                           ` Willy Tarreau [this message]
2018-01-11 20:00                     ` Dave Hansen
2018-01-11 17:09                 ` Andy Lutomirski
2018-01-11 17:40                   ` Willy Tarreau
2018-01-11 17:53                     ` Andy Lutomirski
2018-01-11 18:05                       ` Willy Tarreau
2018-01-11 18:15                         ` Dave Hansen
2018-01-11 18:31                           ` Linus Torvalds
2018-01-11 18:25                     ` Linus Torvalds
2018-01-11 18:26                       ` Linus Torvalds
2018-01-11 19:33                         ` Andy Lutomirski
2018-01-12 20:22                           ` Ingo Molnar
2018-01-12 21:18                             ` Andy Lutomirski
2018-01-12 21:54                               ` Willy Tarreau
2018-01-11 21:59                       ` Willy Tarreau
2018-01-12 16:27                       ` David Laight
2018-01-12 17:55                         ` Linus Torvalds
2018-01-12 19:36                           ` Willy Tarreau
2018-01-11 18:35                 ` Dave Hansen
2018-01-11 21:49                   ` Willy Tarreau
  -- strict thread matches above, loose matches on Subject: below --
2018-01-11 23:11 Alexey Dobriyan

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=20180111191130.GH15344@1wt.eu \
    --to=w@1wt.eu \
    --cc=alexei.starovoitov@gmail.com \
    --cc=bp@alien8.de \
    --cc=brgerst@gmail.com \
    --cc=dave.hansen@linux.intel.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=hpa@zytor.com \
    --cc=jpoimboe@redhat.com \
    --cc=keescook@chromium.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luto@kernel.org \
    --cc=mingo@kernel.org \
    --cc=peterz@infradead.org \
    --cc=tglx@linutronix.de \
    --cc=torvalds@linux-foundation.org \
    --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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.