linux-kernel - Re: [RFC, PATCHv1 15/28] x86: detect 5-level paging support

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 for Android: free password hash cracker in your pocket

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

Message-ID: <34A313BB-EB15-4A4C-AB77-BD678118F086@zytor.com>
Date:   Thu, 15 Dec 2016 12:57:43 -0800
From:   hpa@...or.com
To:     Andi Kleen <ak@...ux.intel.com>, Borislav Petkov <bp@...en8.de>
CC:     Linus Torvalds <torvalds@...ux-foundation.org>,
        "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        the arch/x86 maintainers <x86@...nel.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Arnd Bergmann <arnd@...db.de>,
        Dave Hansen <dave.hansen@...el.com>,
        Andy Lutomirski <luto@...capital.net>,
        "linux-arch@...r.kernel.org" <linux-arch@...r.kernel.org>,
        linux-mm <linux-mm@...ck.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [RFC, PATCHv1 15/28] x86: detect 5-level paging support

On December 15, 2016 11:20:17 AM PST, Andi Kleen <ak@...ux.intel.com> wrote:
>
>The code is not calling CPUID in any performance critical path, only
>at initialization. So any discussion about saving a few instructions
>is a complete waste of time.
>
>-Andi

NB: the chief offender is Loadlin, which is still used in some manufacturing flows that depends on a mix of legacy DOS and Linux applications; however, older versions of LILO also have this problem.
-- 
Sent from my Android device with K-9 Mail. Please excuse my brevity.