linux-kernel - Re: [PATCH 2/3] x86/bugs: Fix BHI retpoline check

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: <20240412231648.orlj7lomjaqqj7mz@desk>
Date: Fri, 12 Apr 2024 16:18:21 -0700
From: Pawan Gupta <pawan.kumar.gupta@...ux.intel.com>
To: Josh Poimboeuf <jpoimboe@...nel.org>
Cc: x86@...nel.org, linux-kernel@...r.kernel.org,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Daniel Sneddon <daniel.sneddon@...ux.intel.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Alexandre Chartre <alexandre.chartre@...cle.com>,
	Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>,
	Peter Zijlstra <peterz@...radead.org>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Sean Christopherson <seanjc@...gle.com>,
	Andrew Cooper <andrew.cooper3@...rix.com>,
	Dave Hansen <dave.hansen@...ux.intel.com>,
	Nikolay Borisov <nik.borisov@...e.com>,
	KP Singh <kpsingh@...nel.org>, Waiman Long <longman@...hat.com>,
	Borislav Petkov <bp@...en8.de>, Ingo Molnar <mingo@...nel.org>
Subject: Re: [PATCH 2/3] x86/bugs: Fix BHI retpoline check

On Fri, Apr 12, 2024 at 11:10:33AM -0700, Josh Poimboeuf wrote:
> Confusingly, X86_FEATURE_RETPOLINE doesn't mean retpolines are enabled,
> as it also includes the original "AMD retpoline" which isn't a retpoline
> at all.
> 
> Also replace cpu_feature_enabled() with boot_cpu_has() because this is
> before alternatives are patched and cpu_feature_enabled()'s fallback
> path is slower than plain old boot_cpu_has().
> 
> Fixes: ec9404e40e8f ("x86/bhi: Add BHI mitigation knob")
> Signed-off-by: Josh Poimboeuf <jpoimboe@...nel.org>

Reviewed-by: Pawan Gupta <pawan.kumar.gupta@...ux.intel.com>