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=-7.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 304DEC433E2 for ; Thu, 3 Sep 2020 22:46:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EDBF720716 for ; Thu, 3 Sep 2020 22:46:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="oZ5KzCEi" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729582AbgICWqP (ORCPT ); Thu, 3 Sep 2020 18:46:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56462 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729438AbgICWqL (ORCPT ); Thu, 3 Sep 2020 18:46:11 -0400 Received: from mail-pg1-x544.google.com (mail-pg1-x544.google.com [IPv6:2607:f8b0:4864:20::544]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8FDD3C061245 for ; Thu, 3 Sep 2020 15:46:11 -0700 (PDT) Received: by mail-pg1-x544.google.com with SMTP id g29so3284833pgl.2 for ; Thu, 03 Sep 2020 15:46:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=5TqmD5EyVPuB9TiyITqacSmLzI3cDbmlqWUeyi+ujCg=; b=oZ5KzCEi7wKIrEEj86amUMkUmItIM2KtyMb6kJV1Bx2j+6SLbFuob0rHAOq9f5nYH0 BvcS2/vu4CZRFtoI7y0Mt062eAYVzZTqZzFG2Iu7rRRlhQSIXmNmKgue9t4cr4gsNbj6 cT+JilU0DZpxA7uH2zokAyWWmg9TpkmIfF0Qk= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=5TqmD5EyVPuB9TiyITqacSmLzI3cDbmlqWUeyi+ujCg=; b=ZsB4PVhEPgNP2cyDzM9U7UO+i2MiwpP3KKdtt/TdIExppjQKoRwuq/8ZAhMtRXJ94V 0BSsm9H4I3ivZ5Rh4+rsBgjqmfcVW7UmimcEPAdNFg7YyOBXjnFTry7WxiLaJ83XR3C6 jY/7u2MGrgr9dWjYWz2pk0swkula2Icopz1c+Fldsukp2BFnNXrD2l+tXrfg190saRkN vcd3kyyWs2cOYLr1XQ2R8T9maXCwseKxEdYYzh6ncL38S6FL/Fc+p/bvIXY457bTylvQ C3IREye7fMmjSZMT6vuI1hgPXZpjs7CP3P6dndbRZVQ8v5GCmLwrPVLs4SX1kjtM8ePD ehZg== X-Gm-Message-State: AOAM53097RRzDbLcFwB0aoGzdIb3gJMznzZWiW9XmONp4KZgSXrrldOv n2eEcuff8W13KdtoDfnOYRuK/w== X-Google-Smtp-Source: ABdhPJz0Cu4W/SGUiAG+2DPCBbmeCYnLc7352WExRrDx24NF8XVfzJeuLOmeQkS8ntOwly5Q8T3lkw== X-Received: by 2002:a63:ca12:: with SMTP id n18mr4721941pgi.371.1599173171199; Thu, 03 Sep 2020 15:46:11 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id b18sm3633660pgk.36.2020.09.03.15.46.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 03 Sep 2020 15:46:10 -0700 (PDT) Date: Thu, 3 Sep 2020 15:46:09 -0700 From: Kees Cook To: Sami Tolvanen Cc: Masahiro Yamada , Will Deacon , Peter Zijlstra , Steven Rostedt , Greg Kroah-Hartman , "Paul E. McKenney" , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org Subject: Re: [PATCH v2 26/28] x86, vdso: disable LTO only for vDSO Message-ID: <202009031546.98CA2EF4@keescook> References: <20200624203200.78870-1-samitolvanen@google.com> <20200903203053.3411268-1-samitolvanen@google.com> <20200903203053.3411268-27-samitolvanen@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200903203053.3411268-27-samitolvanen@google.com> Sender: linux-arch-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org On Thu, Sep 03, 2020 at 01:30:51PM -0700, Sami Tolvanen wrote: > Remove the undefined DISABLE_LTO flag from the vDSO, and filter out > CC_FLAGS_LTO flags instead where needed. Note that while we could use > Clang's LTO for the 64-bit vDSO, it won't add noticeable benefit for > the small amount of C code. > > Signed-off-by: Sami Tolvanen Moar DISABLE_LTO... Reviewed-by: Kees Cook -- Kees Cook