linux-kernel - Re: [PATCH v1 07/12] tools/x86/kcpuid: Add rudimentary CPU vendor detection

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: <Z8r5E3wfFyv-n8XK@lx-t490>
Date: Fri, 7 Mar 2025 14:48:03 +0100
From: "Ahmed S. Darwish" <darwi@...utronix.de>
To: Dave Hansen <dave.hansen@...el.com>
Cc: Borislav Petkov <bp@...en8.de>, Ingo Molnar <mingo@...hat.com>,
	Dave Hansen <dave.hansen@...ux.intel.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Andrew Cooper <andrew.cooper3@...rix.com>,
	"H. Peter Anvin" <hpa@...or.com>, x86@...nel.org,
	John Ogness <john.ogness@...utronix.de>, x86-cpuid@...ts.linux.dev,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v1 07/12] tools/x86/kcpuid: Add rudimentary CPU vendor
 detection

On Thu, 06 Mar 2025, Dave Hansen wrote:
>
> So, this is cute and all. But isn't it a _wee_ bit too clever for its
> own good?
>

That was funny, thanks for the laugh :)

> Why not just have a dumb array:
>
> 	{ INTEL, "GenuineIntel" },
> 	{ AMD,   "AuthenticAMD" ],
> 	...
>
> Are we really looking to save a few dozen CPU cycles in this thing? It
> took me at least a minute or two of staring at this thing to figure out
> what the heck it was doing.
>

Indeed.

For some reason I forgot that this is all little-endian and a simple
strcmp() like what the kernel does at get_cpu_vendor() would suffice.

I'll fix it in v2.

Thanks!
Ahmed