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=-8.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 CA235C433E0 for ; Wed, 24 Jun 2020 21:52:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9D88720768 for ; Wed, 24 Jun 2020 21:52:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="gkQ03mH+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388332AbgFXVwi (ORCPT ); Wed, 24 Jun 2020 17:52:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34734 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404903AbgFXVwh (ORCPT ); Wed, 24 Jun 2020 17:52:37 -0400 Received: from mail-pl1-x643.google.com (mail-pl1-x643.google.com [IPv6:2607:f8b0:4864:20::643]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6563CC0613ED for ; Wed, 24 Jun 2020 14:52:37 -0700 (PDT) Received: by mail-pl1-x643.google.com with SMTP id 35so1704475ple.0 for ; Wed, 24 Jun 2020 14:52:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=ZlZyjdUHfTmn42OuhaukPgD3qQeRnM/SwkQPWmFMjno=; b=gkQ03mH+pPQbaY26mXH9tyFtYNKkc69RJVql3zuiAJ9HIg/y5EOgT1k1p8MPr1NS2p 0+9hv/B8bA8y01i7lTNiIORUq/cOqzJHzcy92+dzag7XYVdUX0EM3i8tlsySkKFAcx1W EsBVlaYTjHyKIaqiR5f+zZkVnqGQKjJtrJF7neBM45lEg19dUfITLa6w50pvskzp+H3Q 7+LiARiXwvKUf+3wbAxBMvD0W3zQDujuEi0Ff7RCeS/cXPDUV5GS8pCW67UEdB7YUlbF 0gxAzEoMpBl65jky4H43Nbd4ZEdySbpIt0IKZBbG4xl5q5BlvUG77XQRz/Foyl8g2Bff X4gA== 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=ZlZyjdUHfTmn42OuhaukPgD3qQeRnM/SwkQPWmFMjno=; b=VtohXjXdvjA1bNSxjmmOVDv3qfMDGLpg2irac/15lOUnyPG5Bv/VkJXqoJwMHMG0eV QKVfn7huZzX6A32HEQjBair3dJCu7bY28VZDCjk5bnK8BDuk1UXyGh0dkSOuqs4kTJZH IbdwMQFYaFrATTbifmeQlex2E3Lw8RPcYxgSWFymGqaNr32x7DxCHPGZSRDMhwh/blMG 9cuQkeHmAyVDVefIAM0wghJb1KYefspP+/6nyqYVOduDH7xsuc+v/dNtT9hoNeAautFt 7fDmusASGf2NQn5I73CRlc9bqiWx4G9sfLv7PFDwwB4EDlVmJHtqJQu3WS/eJOZz1d+x Ym5g== X-Gm-Message-State: AOAM531s5Kem5lUSxNDYwdBopoqvvYkOclOjHZ4utFcD/ZFibJVJ7Kvg z9oRp3/X/SwM7g5xX+l3RqdgYQ== X-Google-Smtp-Source: ABdhPJy+JpaxqpHIcJHjR6LpPq5kjrXe0+X/cVoPhow+mRdRGR18dTuC1hpKBoYOG/LhDJ7hbA1ueg== X-Received: by 2002:a17:90a:dc16:: with SMTP id i22mr30660369pjv.84.1593035556605; Wed, 24 Jun 2020 14:52:36 -0700 (PDT) Received: from google.com ([2620:15c:201:2:ce90:ab18:83b0:619]) by smtp.gmail.com with ESMTPSA id 2sm6487093pfa.110.2020.06.24.14.52.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 24 Jun 2020 14:52:35 -0700 (PDT) Date: Wed, 24 Jun 2020 14:52:31 -0700 From: Sami Tolvanen To: Nick Desaulniers Cc: Masahiro Yamada , Will Deacon , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , clang-built-linux , Kernel Hardening , linux-arch , Linux ARM , Linux Kbuild mailing list , LKML , linux-pci@vger.kernel.org, "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" Subject: Re: [PATCH 17/22] arm64: vdso: disable LTO Message-ID: <20200624215231.GC120457@google.com> References: <20200624203200.78870-1-samitolvanen@google.com> <20200624203200.78870-18-samitolvanen@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Wed, Jun 24, 2020 at 01:58:57PM -0700, 'Nick Desaulniers' via Clang Built Linux wrote: > On Wed, Jun 24, 2020 at 1:33 PM Sami Tolvanen wrote: > > > > Filter out CC_FLAGS_LTO for the vDSO. > > Just curious about this patch (and the following one for x86's vdso), > do you happen to recall specifically what the issues with the vdso's > are? I recall the compiler optimizing away functions at some point, but as LTO is not really needed in the vDSO, it's just easiest to disable it there. Sami