linux-kernel - Re: [PATCH] x86: static_cpu_has_safe: discard dynamic check after init

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: <D8F73F27-54E5-4791-8E77-CA68433FA4EA@zytor.com>
Date:	Wed, 20 Jan 2016 06:48:30 -0800
From:	"H. Peter Anvin" <hpa@...or.com>
To:	Borislav Petkov <bp@...e.de>
CC:	Brian Gerst <brgerst@...il.com>,
	the arch/x86 maintainers <x86@...nel.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Ingo Molnar <mingo@...nel.org>,
	Denys Vlasenko <dvlasenk@...hat.com>,
	Andy Lutomirski <luto@...capital.net>,
	Linus Torvalds <torvalds@...ux-foundation.org>
Subject: Re: [PATCH] x86: static_cpu_has_safe: discard dynamic check after init

On January 20, 2016 3:05:19 AM PST, Borislav Petkov <bp@...e.de> wrote:
>On Wed, Jan 20, 2016 at 02:55:24AM -0800, H. Peter Anvin wrote:
>> How about:
>> 
>> section for code used exclusively before alternatives are run.  All
>references to such code must be patched out by alternatives, normally
>by using a patch with X86_FEATURE_ALWAYS.
>> 
>> See static_cpu_has() for an example.
>
>Sure.
>
>My thinking was to make it a bit more generic so that if we decide to
>do
>some different monkey business with the alternatives, to put stuff in
>there too.
>
>But we can always change that later - it's not like it is user-visible.

I don't think the verbiage I suggested in any way disagrees with that notion.
-- 
Sent from my Android device with K-9 Mail. Please excuse brevity and formatting.