linux-kernel - RE: [PATCH v2 2/5] x86/bugs: Use early_param for spectre

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:
 <LV3PR12MB9265EFE40F2C8EB7C15BBD06943DA@LV3PR12MB9265.namprd12.prod.outlook.com>
Date: Fri, 22 Aug 2025 14:12:55 +0000
From: "Kaplan, David" <David.Kaplan@....com>
To: Borislav Petkov <bp@...en8.de>
CC: Thomas Gleixner <tglx@...utronix.de>, Peter Zijlstra
	<peterz@...radead.org>, Josh Poimboeuf <jpoimboe@...nel.org>, Pawan Gupta
	<pawan.kumar.gupta@...ux.intel.com>, Ingo Molnar <mingo@...hat.com>, Dave
 Hansen <dave.hansen@...ux.intel.com>, "x86@...nel.org" <x86@...nel.org>, "H .
 Peter Anvin" <hpa@...or.com>, "linux-kernel@...r.kernel.org"
	<linux-kernel@...r.kernel.org>
Subject: RE: [PATCH v2 2/5] x86/bugs: Use early_param for spectre_v2

[AMD Official Use Only - AMD Internal Distribution Only]

> -----Original Message-----
> From: Borislav Petkov <bp@...en8.de>
> Sent: Friday, August 22, 2025 6:49 AM
> To: Kaplan, David <David.Kaplan@....com>
> Cc: Thomas Gleixner <tglx@...utronix.de>; Peter Zijlstra <peterz@...radead.org>;
> Josh Poimboeuf <jpoimboe@...nel.org>; Pawan Gupta
> <pawan.kumar.gupta@...ux.intel.com>; Ingo Molnar <mingo@...hat.com>; Dave
> Hansen <dave.hansen@...ux.intel.com>; x86@...nel.org; H . Peter Anvin
> <hpa@...or.com>; linux-kernel@...r.kernel.org
> Subject: Re: [PATCH v2 2/5] x86/bugs: Use early_param for spectre_v2
>
> Caution: This message originated from an External Source. Use proper caution
> when opening attachments, clicking links, or responding.
>
>
> On Tue, Aug 19, 2025 at 02:21:57PM -0500, David Kaplan wrote:
> > +static void __init spectre_v2_check_cmd(void)
>
> Why the separate function?
>
> This can simply go in spectre_v2_select_mitigation() before the switch-case
> like with all the others *_select_mitigation() functions...

It could, but I felt this was a way to logically separate the code vs having one giant function.  All the code in spectre_v2_check_cmd() does one thing: verifies if the chosen command is possible on this system.  The rest of spectre_v2_select_mitigation() then uses the cmd to actually pick a mitigation.

Since these were two distinct flows, I thought having a separate function made sense to make the code more readable.  But that was just my opinion, I won't object if you want to inline it.

--David Kaplan