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=-18.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_IN_DEF_DKIM_WL autolearn=ham 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 5F554C2D0E4 for ; Fri, 20 Nov 2020 23:54:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 16A50223B0 for ; Fri, 20 Nov 2020 23:54:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="mdmSYKuo" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728318AbgKTXx7 (ORCPT ); Fri, 20 Nov 2020 18:53:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35262 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726739AbgKTXx6 (ORCPT ); Fri, 20 Nov 2020 18:53:58 -0500 Received: from mail-pf1-x441.google.com (mail-pf1-x441.google.com [IPv6:2607:f8b0:4864:20::441]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C0D71C0613CF for ; Fri, 20 Nov 2020 15:53:58 -0800 (PST) Received: by mail-pf1-x441.google.com with SMTP id y7so9386281pfq.11 for ; Fri, 20 Nov 2020 15:53:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=/9QmQzu0viMhe1+E2AuJjw4yABAqeWJl/tuV7zSeb+U=; b=mdmSYKuoJmPQiSSZKAXRHrhaYfKRSQA9hE/wfOsOCkhwS+3+67n+lejlrZY4HtZfn/ a2ORoKHB2+RW61Vt9T9zrAHoM1RsQbsuWV47pPf93KFSlEHy1Tfio9hzAUE4BkPNXx+I YITKk0YEENSGCNohJ36jZOmfNM0ry/U9Rv8sczK8LJbtzspnCR2SDBjJ4zad2AR6UovQ Szo2WkElnVp3Pq1aFadmc5JzwZozrsYu/68ODALQuad6JmMLMpwoXKqfBusvVuclgTF+ rSwKmAgZg2oXKzT79ocvKhy7QjjLbUii5XJDdT+bt/WFOVYQqnt9FCLWzuGSaXf0zzOP TH/g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=/9QmQzu0viMhe1+E2AuJjw4yABAqeWJl/tuV7zSeb+U=; b=ce9M5Wjt+Jn25EUJ48Wb+6svF+ZwRn+bm0NLP9wJCM3kyXxcEdBrEhL1ePj2p7nJLj wRlReP35bQfBHWljn0Xe6aYMeMPm6ccABuwj7M37V86ztkHKbkRaq7x90vEHenOA7i14 bqwAIZsxb2e0SCGUlbaQo0dhBPo0cLMkx0Cw/O0spWN2eq6Ts8wYWCb2eXNC+wffe+pd 95oBH7sBvH4MG+X9tcf0DVgyXhqKUNbvtmTu15Xo9CxPh3jt6EGHnGB2tmLm+/I8CrLC qIpt+hiuVZNqT9KtwTId+vYlQ6PpdD/IFFpCZM/z4hFjTSApqeqlyZVWYHlQc+ps11Qi A7NA== X-Gm-Message-State: AOAM532csKp5YMDP6mY8cLDF0Z93SFfAo/+9lKwX4C79OYHQnE68wy10 D9MBpIaS4j3JPrMeIY4/sYRSIfUQeWtxyKrOldrXfA== X-Google-Smtp-Source: ABdhPJy2DGSHmfFcAh4bM/VKta4IGQmsyfxYSHlfpKnMfeL7FrQ+44E3UgsHXg0jgCwAXeN0PaduNYVMcO8diBSDC4k= X-Received: by 2002:a17:90a:6b04:: with SMTP id v4mr13286585pjj.101.1605916438104; Fri, 20 Nov 2020 15:53:58 -0800 (PST) MIME-Version: 1.0 References: <20201118220731.925424-1-samitolvanen@google.com> In-Reply-To: From: Nick Desaulniers Date: Fri, 20 Nov 2020 15:53:45 -0800 Message-ID: Subject: Re: [PATCH v7 00/17] Add support for Clang LTO To: Ard Biesheuvel Cc: Sami Tolvanen , Masahiro Yamada , Steven Rostedt , Will Deacon , Josh Poimboeuf , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , clang-built-linux , Kernel Hardening , linux-arch , Linux ARM , Linux Kbuild mailing list , LKML , PCI , Alistair Delva Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 20, 2020 at 3:30 PM Ard Biesheuvel wrote: > > On Fri, 20 Nov 2020 at 21:19, Nick Desaulniers wrote: > > > > On Fri, Nov 20, 2020 at 2:30 AM Ard Biesheuvel wrote: > > > > > > On Thu, 19 Nov 2020 at 00:42, Nick Desaulniers wrote: > > > > > > > > Thanks for continuing to drive this series Sami. For the series, > > > > > > > > Tested-by: Nick Desaulniers > > > > > > > > I did virtualized boot tests with the series applied to aarch64 > > > > defconfig without CONFIG_LTO, with CONFIG_LTO_CLANG, and a third time > > > > with CONFIG_THINLTO. If you make changes to the series in follow ups, > > > > please drop my tested by tag from the modified patches and I'll help > > > > re-test. Some minor feedback on the Kconfig change, but I'll post it > > > > off of that patch. > > > > > > > > > > When you say 'virtualized" do you mean QEMU on x86? Or actual > > > virtualization on an AArch64 KVM host? > > > > aarch64 guest on x86_64 host. If you have additional configurations > > that are important to you, additional testing help would be > > appreciated. > > > > Could you run this on an actual phone? Or does Android already ship > with this stuff? By `this`, if you mean "the LTO series", it has been shipping on Android phones for years now, I think it's even required in the latest release. If you mean "the LTO series + mainline" on a phone, well there's the android-mainline of https://android.googlesource.com/kernel/common/, in which this series was recently removed in order to facilitate rebasing Android's patches on ToT-mainline until getting the series landed upstream. Bit of a chicken and the egg problem there. If you mean "the LTO series + mainline + KVM" on a phone; I don't know the precise state of aarch64 KVM and Android (Will or Marc would know). We did experiment recently with RockPI's for aach64 KVM, IIRC; I think Android is tricky as it still requires A64+A32/T32 chipsets, Alistair would know more. Might be interesting to boot a virtualized (or paravirtualized?) guest built with LTO in a host built with LTO for sure, but I don't know if we have tried that yet (I think we did try LTO guests of android kernels, but I think they were on the stock RockPI host BSP image IIRC). > > > The distinction is important here, given the potential impact of LTO > > > on things that QEMU simply does not model when it runs in TCG mode on > > > a foreign host architecture. -- Thanks, ~Nick Desaulniers 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=-8.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_ADSP_CUSTOM_MED,DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 CEE3AC2D0E4 for ; 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Fri, 20 Nov 2020 15:53:58 -0800 (PST) MIME-Version: 1.0 References: <20201118220731.925424-1-samitolvanen@google.com> In-Reply-To: From: Nick Desaulniers Date: Fri, 20 Nov 2020 15:53:45 -0800 Message-ID: Subject: Re: [PATCH v7 00/17] Add support for Clang LTO To: Ard Biesheuvel X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201120_185400_676943_16D72A42 X-CRM114-Status: GOOD ( 29.05 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch , Alistair Delva , Kees Cook , "Paul E. McKenney" , Kernel Hardening , Peter Zijlstra , Greg Kroah-Hartman , Masahiro Yamada , Linux Kbuild mailing list , PCI , LKML , Steven Rostedt , clang-built-linux , Sami Tolvanen , Josh Poimboeuf , Will Deacon , Linux ARM Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Nov 20, 2020 at 3:30 PM Ard Biesheuvel wrote: > > On Fri, 20 Nov 2020 at 21:19, Nick Desaulniers wrote: > > > > On Fri, Nov 20, 2020 at 2:30 AM Ard Biesheuvel wrote: > > > > > > On Thu, 19 Nov 2020 at 00:42, Nick Desaulniers wrote: > > > > > > > > Thanks for continuing to drive this series Sami. For the series, > > > > > > > > Tested-by: Nick Desaulniers > > > > > > > > I did virtualized boot tests with the series applied to aarch64 > > > > defconfig without CONFIG_LTO, with CONFIG_LTO_CLANG, and a third time > > > > with CONFIG_THINLTO. If you make changes to the series in follow ups, > > > > please drop my tested by tag from the modified patches and I'll help > > > > re-test. Some minor feedback on the Kconfig change, but I'll post it > > > > off of that patch. > > > > > > > > > > When you say 'virtualized" do you mean QEMU on x86? Or actual > > > virtualization on an AArch64 KVM host? > > > > aarch64 guest on x86_64 host. If you have additional configurations > > that are important to you, additional testing help would be > > appreciated. > > > > Could you run this on an actual phone? Or does Android already ship > with this stuff? By `this`, if you mean "the LTO series", it has been shipping on Android phones for years now, I think it's even required in the latest release. If you mean "the LTO series + mainline" on a phone, well there's the android-mainline of https://android.googlesource.com/kernel/common/, in which this series was recently removed in order to facilitate rebasing Android's patches on ToT-mainline until getting the series landed upstream. Bit of a chicken and the egg problem there. If you mean "the LTO series + mainline + KVM" on a phone; I don't know the precise state of aarch64 KVM and Android (Will or Marc would know). We did experiment recently with RockPI's for aach64 KVM, IIRC; I think Android is tricky as it still requires A64+A32/T32 chipsets, Alistair would know more. Might be interesting to boot a virtualized (or paravirtualized?) guest built with LTO in a host built with LTO for sure, but I don't know if we have tried that yet (I think we did try LTO guests of android kernels, but I think they were on the stock RockPI host BSP image IIRC). > > > The distinction is important here, given the potential impact of LTO > > > on things that QEMU simply does not model when it runs in TCG mode on > > > a foreign host architecture. -- Thanks, ~Nick Desaulniers _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel 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=-18.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_IN_DEF_DKIM_WL autolearn=unavailable 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 2500DC2D0E4 for ; Fri, 20 Nov 2020 23:54:20 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 1FE6C223B0 for ; Fri, 20 Nov 2020 23:54:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="mdmSYKuo" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1FE6C223B0 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20439-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 21962 invoked by uid 550); 20 Nov 2020 23:54:11 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 21942 invoked from network); 20 Nov 2020 23:54:10 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=/9QmQzu0viMhe1+E2AuJjw4yABAqeWJl/tuV7zSeb+U=; b=mdmSYKuoJmPQiSSZKAXRHrhaYfKRSQA9hE/wfOsOCkhwS+3+67n+lejlrZY4HtZfn/ a2ORoKHB2+RW61Vt9T9zrAHoM1RsQbsuWV47pPf93KFSlEHy1Tfio9hzAUE4BkPNXx+I YITKk0YEENSGCNohJ36jZOmfNM0ry/U9Rv8sczK8LJbtzspnCR2SDBjJ4zad2AR6UovQ Szo2WkElnVp3Pq1aFadmc5JzwZozrsYu/68ODALQuad6JmMLMpwoXKqfBusvVuclgTF+ rSwKmAgZg2oXKzT79ocvKhy7QjjLbUii5XJDdT+bt/WFOVYQqnt9FCLWzuGSaXf0zzOP TH/g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=/9QmQzu0viMhe1+E2AuJjw4yABAqeWJl/tuV7zSeb+U=; b=f3TWkvruIPFG2C76UdLRc44BzkYDLt8ldPvETkz6f8eBKKjelKrzjJe4gPmC9tt92Q OaMVMnZgesymgE1fvA/Ra6gC8oTFvf9Ba6Gmt196VnbyrAml+XJLZpYpOM+PHM8RmrlB /JyIrqVnZGFzhN6bTs9pys6KTuBsxs1JIpSEwBDQP53ym2XxeDM7F5fbe6hLhrf3HnJn 18+eDqwqa9GHKQF9z0wu/EwLKMrl8xfQK9c8q4/x4N+8lvytugkZnWmfNkV/an3/zvL9 Jeb2G22DWeYG0IrOmWa1zG4risa0Xh6daV7m/rBHxHC3LMfRzvtrYQVzWOyI+RU5qj3z I4AQ== X-Gm-Message-State: AOAM530aD47kfjPI6bcavtX4DapQpMc+mYq1L0pAw/Jh0H1pjOlR5cmH s51udwiFAb+BEU2E/QlEOVy+dnOpPPgZncxcfhDXrA== X-Google-Smtp-Source: ABdhPJy2DGSHmfFcAh4bM/VKta4IGQmsyfxYSHlfpKnMfeL7FrQ+44E3UgsHXg0jgCwAXeN0PaduNYVMcO8diBSDC4k= X-Received: by 2002:a17:90a:6b04:: with SMTP id v4mr13286585pjj.101.1605916438104; Fri, 20 Nov 2020 15:53:58 -0800 (PST) MIME-Version: 1.0 References: <20201118220731.925424-1-samitolvanen@google.com> In-Reply-To: From: Nick Desaulniers Date: Fri, 20 Nov 2020 15:53:45 -0800 Message-ID: Subject: Re: [PATCH v7 00/17] Add support for Clang LTO To: Ard Biesheuvel Cc: Sami Tolvanen , Masahiro Yamada , Steven Rostedt , Will Deacon , Josh Poimboeuf , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , clang-built-linux , Kernel Hardening , linux-arch , Linux ARM , Linux Kbuild mailing list , LKML , PCI , Alistair Delva Content-Type: text/plain; charset="UTF-8" On Fri, Nov 20, 2020 at 3:30 PM Ard Biesheuvel wrote: > > On Fri, 20 Nov 2020 at 21:19, Nick Desaulniers wrote: > > > > On Fri, Nov 20, 2020 at 2:30 AM Ard Biesheuvel wrote: > > > > > > On Thu, 19 Nov 2020 at 00:42, Nick Desaulniers wrote: > > > > > > > > Thanks for continuing to drive this series Sami. For the series, > > > > > > > > Tested-by: Nick Desaulniers > > > > > > > > I did virtualized boot tests with the series applied to aarch64 > > > > defconfig without CONFIG_LTO, with CONFIG_LTO_CLANG, and a third time > > > > with CONFIG_THINLTO. If you make changes to the series in follow ups, > > > > please drop my tested by tag from the modified patches and I'll help > > > > re-test. Some minor feedback on the Kconfig change, but I'll post it > > > > off of that patch. > > > > > > > > > > When you say 'virtualized" do you mean QEMU on x86? Or actual > > > virtualization on an AArch64 KVM host? > > > > aarch64 guest on x86_64 host. If you have additional configurations > > that are important to you, additional testing help would be > > appreciated. > > > > Could you run this on an actual phone? Or does Android already ship > with this stuff? By `this`, if you mean "the LTO series", it has been shipping on Android phones for years now, I think it's even required in the latest release. If you mean "the LTO series + mainline" on a phone, well there's the android-mainline of https://android.googlesource.com/kernel/common/, in which this series was recently removed in order to facilitate rebasing Android's patches on ToT-mainline until getting the series landed upstream. Bit of a chicken and the egg problem there. If you mean "the LTO series + mainline + KVM" on a phone; I don't know the precise state of aarch64 KVM and Android (Will or Marc would know). We did experiment recently with RockPI's for aach64 KVM, IIRC; I think Android is tricky as it still requires A64+A32/T32 chipsets, Alistair would know more. Might be interesting to boot a virtualized (or paravirtualized?) guest built with LTO in a host built with LTO for sure, but I don't know if we have tried that yet (I think we did try LTO guests of android kernels, but I think they were on the stock RockPI host BSP image IIRC). > > > The distinction is important here, given the potential impact of LTO > > > on things that QEMU simply does not model when it runs in TCG mode on > > > a foreign host architecture. -- Thanks, ~Nick Desaulniers