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[23.128.96.18]) by mx.google.com with ESMTP id a6si2495213ejj.398.2020.11.20.15.32.44; Fri, 20 Nov 2020 15:33:07 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=RZzdH79P; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728614AbgKTXap (ORCPT + 99 others); Fri, 20 Nov 2020 18:30:45 -0500 Received: from mail.kernel.org ([198.145.29.99]:49456 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726719AbgKTXap (ORCPT ); Fri, 20 Nov 2020 18:30:45 -0500 Received: from mail-oi1-f171.google.com (mail-oi1-f171.google.com [209.85.167.171]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E21D92240B; Fri, 20 Nov 2020 23:30:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605915044; bh=pAOPOCc79X5vSW6IJcHVGfCdHUlnqpSzr+lv+zQxwCc=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=RZzdH79P6J5urfJDjwQdKxx5LnTEOmSru+Pngr2whnPMGGF/5iys8b3oGoRp3fiC2 B9zPEK+hV1YvwzBAM2H5HZymjsteXPWwOamkRpmbJpb2YTeAXwp7dY7auSdWBrz/F2 /N80r04AHKKCoaM6D2sPwvKPyEcCtIgwahDH+KeA= Received: by mail-oi1-f171.google.com with SMTP id a130so4261361oif.7; Fri, 20 Nov 2020 15:30:43 -0800 (PST) X-Gm-Message-State: AOAM533pXk4s93Kp6xS5SPeBjmQHE6F7HrGLtTmGW9MvJrhvPJEB/PXB Igq2Kgez7AHQx295Eujy15HDa2XxY6dtvlnIMBk= X-Received: by 2002:aca:5c82:: with SMTP id q124mr8196235oib.33.1605915043305; Fri, 20 Nov 2020 15:30:43 -0800 (PST) MIME-Version: 1.0 References: <20201118220731.925424-1-samitolvanen@google.com> In-Reply-To: From: Ard Biesheuvel Date: Sat, 21 Nov 2020 00:30:32 +0100 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v7 00/17] Add support for Clang LTO To: Nick Desaulniers 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, 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? > > > > 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