linux-kernel - Re: [PATCHv3 0/8] Linear Address Masking enabling

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20220616234352.2h4f64a4fw46atrs@black.fi.intel.com>
Date:   Fri, 17 Jun 2022 02:43:52 +0300
From:   "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>
To:     "Edgecombe, Rick P" <rick.p.edgecombe@...el.com>
Cc:     "peterz@...radead.org" <peterz@...radead.org>,
        "Lutomirski, Andy" <luto@...nel.org>,
        "dave.hansen@...ux.intel.com" <dave.hansen@...ux.intel.com>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "hjl.tools@...il.com" <hjl.tools@...il.com>,
        "linux-mm@...ck.org" <linux-mm@...ck.org>,
        "kcc@...gle.com" <kcc@...gle.com>,
        "andreyknvl@...il.com" <andreyknvl@...il.com>,
        "ak@...ux.intel.com" <ak@...ux.intel.com>,
        "dvyukov@...gle.com" <dvyukov@...gle.com>,
        "x86@...nel.org" <x86@...nel.org>,
        "ryabinin.a.a@...il.com" <ryabinin.a.a@...il.com>,
        "glider@...gle.com" <glider@...gle.com>
Subject: Re: [PATCHv3 0/8] Linear Address Masking enabling

On Thu, Jun 16, 2022 at 10:52:14PM +0000, Edgecombe, Rick P wrote:
> On Fri, 2022-06-10 at 17:35 +0300, Kirill A. Shutemov wrote:
> > Linear Address Masking[1] (LAM) modifies the checking that is applied
> > to
> > 64-bit linear addresses, allowing software to use of the untranslated
> > address bits for metadata.
> > 
> > The patchset brings support for LAM for userspace addresses.
> 
> Arm has this documentation about which memory operations support being
> passed tagged pointers, and which do not:
> Documentation/arm64/tagged-address-abi.rst
> 
> Is the idea that LAM would have something similar, or exactly mirror
> the arm ABI? It seems like it is the same right now. Should the docs be
> generalized?

It is somewhat similar, but not exact. ARM TBI interface implies tag size
and placement. ARM TBI is per-thread and LAM is per-process.

-- 
 Kirill A. Shutemov