From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8C569C433DB for ; Fri, 5 Mar 2021 11:50:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3595D64F76 for ; Fri, 5 Mar 2021 11:50:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229740AbhCELtt (ORCPT ); Fri, 5 Mar 2021 06:49:49 -0500 Received: from bilbo.ozlabs.org ([203.11.71.1]:50023 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229672AbhCELtl (ORCPT ); Fri, 5 Mar 2021 06:49:41 -0500 Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4DsQy96jkXz9sWL; Fri, 5 Mar 2021 22:49:37 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ellerman.id.au; s=201909; t=1614944979; bh=MFuEr/zpCREmU8rWGDeBRzuATbhdbCM1oGMnXg6xVJA=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=iqqfOFNX9EQlJSH/QhZZ0p6dE3IkuDgX/+x3w6yrBguuBdJT+jY7FX2diXMKV0ALl +keQy4Z341L6a8EZLdY7Gl8NJU5gZS0MAfOpTNZiAzBO2QKsrzfaiGylrzMQIPZQm3 CSxGVfSC5Iw41blS8SDq2alD7gJzxyOUQf0AwLVw7+h+Ps7feiYoEJ/JVJ/gr/fxMj UtLYMOgbVPH16NxnEsyLRgZVmjPul7J53e1mOrzcI3Mt/hrBZc2Moqi3m3N9hqpVue yQDAjSKkliB/ApMNL2rDGxjiCxQ9sxw2Xi1NaGtkMwf/LJy+eKyHcKqwqOAypP9nXG VqDsphppeLQ5A== From: Michael Ellerman To: Marco Elver , Christophe Leroy Cc: Alexander Potapenko , Benjamin Herrenschmidt , Paul Mackerras , Dmitry Vyukov , LKML , linuxppc-dev@lists.ozlabs.org, kasan-dev Subject: Re: [RFC PATCH v1] powerpc: Enable KFENCE for PPC32 In-Reply-To: References: <08a96c5d-4ae7-03b4-208f-956226dee6bb@csgroup.eu> <7270e1cc-bb6b-99ee-0043-08a027b8d83a@csgroup.eu> <874khqry78.fsf@mpe.ellerman.id.au> Date: Fri, 05 Mar 2021 22:49:36 +1100 Message-ID: <87tupprfan.fsf@mpe.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Marco Elver writes: ... > > The choice is between: > > 1. ARCH_FUNC_PREFIX (as a matter of fact, the ARCH_FUNC_PREFIX patch > is already in -mm). Perhaps we could optimize it further, by checking > ARCH_FUNC_PREFIX in buf, and advancing buf like you propose, but I'm > not sure it's worth worrying about. > > 2. The dynamic solution that I proposed that does not use a hard-coded > '.' (or some variation thereof). > > Please tell me which solution you prefer, 1 or 2 -- I'd like to stop > bikeshedding here. If there's a compelling argument for hard-coding > the '.' in non-arch code, please clarify, but otherwise I'd like to > keep arch-specific things out of generic code. It's your choice, I was just trying to minimise the size of the wart you have to carry in kfence code to deal with it. The ARCH_FUNC_PREFIX solution is fine by me. cheers