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=-4.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 C8D74C43603 for ; Thu, 12 Dec 2019 04:52:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 993B2206C3 for ; Thu, 12 Dec 2019 04:52:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576126352; bh=wU7MOiAKcmA1brj18jg6XBrLjIBGxB5YTGkfdP4OipE=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=I014ZG52Dc6I9B+833fQcRj3o3TH91EKt4lWq4feE44t1BR9lvlYcdBJkYtzIhYNK ojVm/y/txXcykH3VA7wshMkLMisofMskW/+bGopDzT9K2/qg+21IZ6flAN9JL6NY6B tf4Ujjq4fCwOeWvq5g1lYSr3nH05lx8MGe3l2NwQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727906AbfLLEwb (ORCPT ); Wed, 11 Dec 2019 23:52:31 -0500 Received: from conssluserg-02.nifty.com ([210.131.2.81]:33731 "EHLO conssluserg-02.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727833AbfLLEwb (ORCPT ); Wed, 11 Dec 2019 23:52:31 -0500 Received: from mail-ua1-f53.google.com (mail-ua1-f53.google.com [209.85.222.53]) (authenticated) by conssluserg-02.nifty.com with ESMTP id xBC4q23H013067 for ; Thu, 12 Dec 2019 13:52:03 +0900 DKIM-Filter: OpenDKIM Filter v2.10.3 conssluserg-02.nifty.com xBC4q23H013067 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nifty.com; s=dec2015msa; t=1576126323; bh=TyTFhnCKN2YT9bgwjekkQfef7OcPW8tA1OCfAFWZK7Q=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=A7yKkfSAcs9WjoquxzLh7cMFno8KGaAwFSH0NIn9ESuM6QSL/TUGtVFFbTa8/xu0r wQVmdp/Pe9koFAp6WKmBLh3ri+Kl32LgSe8/nZ/SMkRf44czRfl6X3ZcGUSrXDa+Mn oWW1ouviggHFzlGX53/yURcUMqqueqGKosTv0OZ45wjBVfTjwjF6Y4nRnEIS9p4yLd 6LXBVMLZH3Yfr4SVlGxe6+4SxWgBxDzjlRKpTAp0QvK6vpue1IzqMBBfmO/qKsz6/J IHf8jAfgfV4pGvwPlGtVfoy2SCebW0f/u4ssKUQpcIk0cJC+miKFQW2VdBnFpvfn0q jGcgniX76NfKQ== X-Nifty-SrcIP: [209.85.222.53] Received: by mail-ua1-f53.google.com with SMTP id i31so353672uae.13 for ; Wed, 11 Dec 2019 20:52:03 -0800 (PST) X-Gm-Message-State: APjAAAUonxWcDiWvL2H72wOZLifIAF/lrBuQy9tepU3IuzKeB9DlUOVj OZOcwUgynAcwekPXQCx9CioQnVbdOlp5Evw1ajE= X-Google-Smtp-Source: APXvYqz/xKbHHZjwUWVynvq0LAVaNNjyZIbkX3XCyi5Zubq0qkD3LmQSy2gKjjpQPjA4me5ky2NjvvlFXvzrYZyE/Xw= X-Received: by 2002:ab0:6509:: with SMTP id w9mr6474644uam.121.1576126321925; Wed, 11 Dec 2019 20:52:01 -0800 (PST) MIME-Version: 1.0 References: <20191211133951.401933-1-arnd@arndb.de> In-Reply-To: <20191211133951.401933-1-arnd@arndb.de> From: Masahiro Yamada Date: Thu, 12 Dec 2019 13:51:26 +0900 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] gcc-plugins: make it possible to disable CONFIG_GCC_PLUGINS again To: Arnd Bergmann Cc: Kees Cook , Emese Revfy , Ard Biesheuvel , Andrey Ryabinin , Kernel Hardening , Linux Kernel Mailing List , clang-built-linux Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 11, 2019 at 10:40 PM Arnd Bergmann wrote: > > I noticed that randconfig builds with gcc no longer produce a lot of > ccache hits, unlike with clang, and traced this back to plugins > now being enabled unconditionally if they are supported. > > I am now working around this by adding > > export CCACHE_COMPILERCHECK=/usr/bin/size -A %compiler% > > to my top-level Makefile. This changes the heuristic that ccache uses > to determine whether the plugins are the same after a 'make clean'. > > However, it also seems that being able to just turn off the plugins is > generally useful, at least for build testing it adds noticeable overhead > but does not find a lot of bugs additional bugs, and may be easier for > ccache users than my workaround. > > Fixes: 9f671e58159a ("security: Create "kernel hardening" config area") > Signed-off-by: Arnd Bergmann > --- Reviewed-by: Masahiro Yamada -- Best Regards Masahiro Yamada