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=-4.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, 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 7BB99C4363D for ; Wed, 30 Sep 2020 21:10:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2DA742075F for ; Wed, 30 Sep 2020 21:10:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="aznXL+Mf" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728721AbgI3VKg (ORCPT ); Wed, 30 Sep 2020 17:10:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38660 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725372AbgI3VKg (ORCPT ); Wed, 30 Sep 2020 17:10:36 -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 55752C061755 for ; Wed, 30 Sep 2020 14:10:36 -0700 (PDT) Received: by mail-pg1-x544.google.com with SMTP id m34so1925286pgl.9 for ; Wed, 30 Sep 2020 14:10:36 -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=43NmDXRdfvytQQYY6+SkI5I3v0G1ZKlfq1R/B+8Rbe8=; b=aznXL+Mf1oo937XoxBdAUWYbrGQBox+mHPLXOBi8fxELvJxmtN4Oh2fdCubtsfNRrA rDHSxjRXgFROvxwZKbrgkOQaw+IdYULTR8nRNYUFnd02K6q1DKbVRP6qGTIrAq/ntqIt uicIip4Sy8y/dZqila87XWTqZiy3eaEQT/WgQ= 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=43NmDXRdfvytQQYY6+SkI5I3v0G1ZKlfq1R/B+8Rbe8=; b=FGLmJ0Xw3rBNX+os/VkHMNsD3GLjDDTXy97OEWd/YQ4ByTrqxHkXZKMlgXRGESlfAU 9Byusr/CRzNCZ2mEKkRY9dSKPvZxQ1DJaayAZ4ytGXqI9o9wbyN9XK0ldHvrK9Ln90/X wSU32j0IM8gm20EnG3YwYqyArrDlfaFwgEEOMNtPQUV6QLl7tdHSLm8x6UapBo4+WvZ7 Rx3DVHyH4gLu6lCDt1tuAvNUm0mhjX02l+uGHiMODGFTPOGKmIz0lCfLBAwauLY3O6zX DHRRE5WGrVKGb+VpsgHI7cAEmdPKwThwCY9gL6yiZU3T7LAaIActpf0NMKsd2kvg2p5q djFw== X-Gm-Message-State: AOAM531FReiiWWhl/DTJxIHvSdWlls3WaC3HOxLfqK5LMU9MqKmtEgst 8mfjLw0UT3MNGstNTGG4k9V31Q== X-Google-Smtp-Source: ABdhPJyw4kR2hvM1gD9zLPKC5ogvJTlrWuluJmqFM9fB7y/1oreMiPXLmURVREruQgKi3Vr48qMMIg== X-Received: by 2002:a17:902:c40d:b029:d2:562d:db9 with SMTP id k13-20020a170902c40db02900d2562d0db9mr4239380plk.46.1601500235715; Wed, 30 Sep 2020 14:10:35 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id n2sm3182853pja.41.2020.09.30.14.10.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 30 Sep 2020 14:10:34 -0700 (PDT) Date: Wed, 30 Sep 2020 14:10:33 -0700 From: Kees Cook To: Peter Zijlstra , Steven Rostedt Cc: Sami Tolvanen , Masahiro Yamada , Will Deacon , 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 v4 00/29] Add support for Clang LTO Message-ID: <202009301402.27A40DD1@keescook> References: <20200929214631.3516445-1-samitolvanen@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200929214631.3516445-1-samitolvanen@google.com> Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Tue, Sep 29, 2020 at 02:46:02PM -0700, Sami Tolvanen wrote: > Furthermore, patches 4-8 include Peter's patch for generating > __mcount_loc with objtool, and build system changes to enable it on > x86. With these patches, we no longer need to annotate functions > that have non-call references to __fentry__ with LTO, which makes > supporting dynamic ftrace much simpler. Peter, can you take patches 4-8 into -tip? I think it'd make sense to keep them together. Steven, it sounds like you're okay with the changes (i.e. Sami showed the one concern you had was already handled)? Getting these into v5.10 would be really really nice. I'd really like to get the tree-spanning prerequisites nailed down for this series. It's been difficult to coordinate given the multiple maintainers. :) Specifically these patches: Peter Zijlstra (1): objtool: Add a pass for generating __mcount_loc Sami Tolvanen (4): objtool: Don't autodetect vmlinux.o tracing: move function tracer options to Kconfig tracing: add support for objtool mcount x86, build: use objtool mcount https://lore.kernel.org/lkml/20200929214631.3516445-5-samitolvanen@google.com/ https://lore.kernel.org/lkml/20200929214631.3516445-6-samitolvanen@google.com/ https://lore.kernel.org/lkml/20200929214631.3516445-7-samitolvanen@google.com/ https://lore.kernel.org/lkml/20200929214631.3516445-8-samitolvanen@google.com/ https://lore.kernel.org/lkml/20200929214631.3516445-9-samitolvanen@google.com/ Thanks! -- Kees Cook