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=1.3 required=3.0 tests=DKIM_SIGNED,FSL_HELO_FAKE, MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID,USER_AGENT_MUTT 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 84EC5C6778A for ; Tue, 3 Jul 2018 08:39:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3FE4C20844 for ; Tue, 3 Jul 2018 08:39:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="C4Z2T+rI" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3FE4C20844 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933013AbeGCIjA (ORCPT ); Tue, 3 Jul 2018 04:39:00 -0400 Received: from mail-wm0-f67.google.com ([74.125.82.67]:50656 "EHLO mail-wm0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754218AbeGCIi5 (ORCPT ); Tue, 3 Jul 2018 04:38:57 -0400 Received: by mail-wm0-f67.google.com with SMTP id v25-v6so1383566wmc.0 for ; Tue, 03 Jul 2018 01:38:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=L4FjDvGQgmLVJ5933cjQZXJkW7oGC7E8X7BDzb1+S44=; b=C4Z2T+rIVNuGlgfIaT8li3IkGkAthlG9wyBPNXoUNnJGnF2wK9EV63oo69aHGXDxjH p0rRDNYDbhmHqlAvYD/wSTKkVdin0PpC/DzHmOs+YhBBocli1GftTjkyz/qq3jmRv2Td 8vr37XUNYaHYEqitldQaiVJAUIBVlUmAe8dQM1hxcqJC8p0qT/q5j/iTmtd99FELoyj6 kVuBzrxtjCM8wsSXpbgNe0Dmyitmvn5bkXuFZufuwV+Xcty3pk8nOKzCcjU4BA8Qb45K 7l66qZsCAHDHy4KAwJ2MUIU9n5esBAOQmonl2JErZiOHUfe4zugYgXRbtfK3LRNzLrbA IjKQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=L4FjDvGQgmLVJ5933cjQZXJkW7oGC7E8X7BDzb1+S44=; b=WHsyl62PTyZEeQxO6OZstxZYWxPbAnHxkto+MYqrgV5Xylx3S56U7G+0PjtkVfWSjo ROzIjlBv9MmX4z6q+aa0sIV80yS7qiekrjr+fycsMQcapuCbSgigSEVzC96mrSUFvFsx LXDtax1bQIPrmQ+DdJB4NyeEr/TxjqN22q/jdIArWpy/zNWDYYsQmpbHjyKij+c9pLZ6 fovhYGxNS+g97dpkrDUJXIrHxtfpV3GRAp7qaZWCLFy89xCRg1SbzHJooJusX8A5s3B1 x229kPXpVH/keMYCVlDUJdnxY5FUf66ms7LsDzprga5Sl0lWEGCzLWUGuc0potEXpNYJ olBw== X-Gm-Message-State: APt69E0ub2eWWjzic+eIdpaxSOqp2Z+vzcoCeaXvwBJXUgNryS+jtMUM 0v09yPZDnm5lck8erZTFpcU= X-Google-Smtp-Source: AAOMgpdzeEJ8Pd88fszKd8SxW9P101l+VtG7kdTCb5dmzLI9JUmxDoRuG0P008jnPJTj+LwdASM9og== X-Received: by 2002:a1c:3b54:: with SMTP id i81-v6mr10559445wma.143.1530607136659; Tue, 03 Jul 2018 01:38:56 -0700 (PDT) Received: from gmail.com (2E8B0CD5.catv.pool.telekom.hu. [46.139.12.213]) by smtp.gmail.com with ESMTPSA id y189-v6sm1122101wmd.19.2018.07.03.01.38.54 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 03 Jul 2018 01:38:56 -0700 (PDT) Date: Tue, 3 Jul 2018 10:38:53 +0200 From: Ingo Molnar To: Ard Biesheuvel Cc: Thomas Gleixner , the arch/x86 maintainers , Ingo Molnar , Linux Kernel Mailing List , Arnd Bergmann , Kees Cook , Michael Ellerman , Thomas Garnier , "Serge E. Hallyn" , Bjorn Helgaas , Benjamin Herrenschmidt , Russell King , Paul Mackerras , Catalin Marinas , Petr Mladek , James Morris , Andrew Morton , Nicolas Pitre , Josh Poimboeuf , Steven Rostedt , Sergey Senozhatsky , Linus Torvalds , Jessica Yu , linux-arm-kernel , linuxppc-dev , Will Deacon Subject: Re: [PATCH v9 0/6] add support for relative references in special sections Message-ID: <20180703083853.GA5369@gmail.com> References: <20180626182802.19932-1-ard.biesheuvel@linaro.org> <20180627151510.GE30631@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Ard Biesheuvel wrote: > On 27 June 2018 at 17:15, Will Deacon wrote: > > Hi Ard, > > > > On Tue, Jun 26, 2018 at 08:27:55PM +0200, Ard Biesheuvel wrote: > >> This adds support for emitting special sections such as initcall arrays, > >> PCI fixups and tracepoints as relative references rather than absolute > >> references. This reduces the size by 50% on 64-bit architectures, but > >> more importantly, it removes the need for carrying relocation metadata > >> for these sections in relocatable kernels (e.g., for KASLR) that needs > >> to be fixed up at boot time. On arm64, this reduces the vmlinux footprint > >> of such a reference by 8x (8 byte absolute reference + 24 byte RELA entry > >> vs 4 byte relative reference) > >> > >> Patch #3 was sent out before as a single patch. This series supersedes > >> the previous submission. This version makes relative ksymtab entries > >> dependent on the new Kconfig symbol HAVE_ARCH_PREL32_RELOCATIONS rather > >> than trying to infer from kbuild test robot replies for which architectures > >> it should be blacklisted. > >> > >> Patch #1 introduces the new Kconfig symbol HAVE_ARCH_PREL32_RELOCATIONS, > >> and sets it for the main architectures that are expected to benefit the > >> most from this feature, i.e., 64-bit architectures or ones that use > >> runtime relocations. > >> > >> Patch #2 add support for #define'ing __DISABLE_EXPORTS to get rid of > >> ksymtab/kcrctab sections in decompressor and EFI stub objects when > >> rebuilding existing C files to run in a different context. > > > > I had a small question on patch 3, but it's really for my understanding. > > So, for patches 1-3: > > > > Reviewed-by: Will Deacon > > > > Thanks all. > > Thomas, Ingo, > > Except for the below tweak against patch #3 for powerpc, which may > apparently get confused by an input section called .discard without > any suffixes, this series is good to go, but requires your ack to > proceed, so I would like to ask you to share your comments and/or > objections. Also, any suggestions or recommendations regarding the > route these patches should take are highly appreciated. LGTM: Acked-by: Ingo Molnar Regarding route - I suspect -mm would be good, or any other tree that does a lot of cross-arch testing? Thanks, Ingo