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=-2.5 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, T_DKIMWL_WL_HIGH,URIBL_BLOCKED,USER_AGENT_MUTT 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 B0D1BC28CC5 for ; Wed, 5 Jun 2019 19:26:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8B8DB2083E for ; Wed, 5 Jun 2019 19:26:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559762770; bh=qjRJSmh3TXbUFkpRu9OH/tnhcBCLS0C7KuQKagjLra8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=Ku8UyBMVwhCVLV5owBvbBRzLOOZiWK0paqJGEZ+YoR2OJG4kMKm/KaoZLwjRE5iTd F9hoiT2P3n77WhH97OR/IxI+AzSRI1FouQ87IKYXojmFeJvyHV4pCh9bGCb5Alt0iu pcsE3KNtWfLIGCV7u7p3CDMvYTv/AsIS6wYhUIQ4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726714AbfFET0J (ORCPT ); Wed, 5 Jun 2019 15:26:09 -0400 Received: from mail.kernel.org ([198.145.29.99]:37304 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726305AbfFET0J (ORCPT ); Wed, 5 Jun 2019 15:26:09 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 05DD0206BB; Wed, 5 Jun 2019 19:26:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559762768; bh=qjRJSmh3TXbUFkpRu9OH/tnhcBCLS0C7KuQKagjLra8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=NSRbGiweAyNiIowFSuyaPZv9m6fEh0QethOFuHIgzVSyCrQe0/jGoxSIwANwjHP9m XE9MOjLOKpnxaXEb4pp/Yv65Q8EPuMLVkFWFTNwLSPYEmGgMCWqrf+DRFnl8qsuxl9 JlBdrR5oFCvoby93Y3PJ+Q4yCoc4lkjbfBUmAVmk= Date: Wed, 5 Jun 2019 21:26:06 +0200 From: Greg KH To: Ard Biesheuvel Cc: Rolf Eike Beer , Nick Desaulniers , Linus Torvalds , Matt Fleming , Peter Zijlstra , Thomas Gleixner , linux-efi , Linux Kernel Developers List , stable Subject: Re: Building arm64 EFI stub with -fpie breaks build of 4.9.x (undefined reference to `__efistub__GLOBAL_OFFSET_TABLE_') Message-ID: <20190605192606.GA9483@kroah.com> References: <779905244.a0lJJiZRjM@devpool35> <20190605162626.GA31164@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.12.0 (2019-05-25) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 05, 2019 at 08:42:32PM +0200, Ard Biesheuvel wrote: > On Wed, 5 Jun 2019 at 18:26, Greg KH wrote: > > > > On Wed, Jun 05, 2019 at 05:19:40PM +0200, Rolf Eike Beer wrote: > > > I decided to dig out a toy project which uses a DragonBoard 410c. This has > > > been "running" with kernel 4.9, which I would keep this way for unrelated > > > reasons. The vanilla 4.9 kernel wasn't bootable back then, but it was > > > buildable, which was good enough. > > > > > > Upgrading the kernel to 4.9.180 caused the boot to suddenly fail: > > > > > > aarch64-unknown-linux-gnueabi-ld: ./drivers/firmware/efi/libstub/lib.a(arm64- > > > stub.stub.o): in function `handle_kernel_image': > > > /tmp/e2/build/linux-4.9.139/drivers/firmware/efi/libstub/arm64-stub.c:63: > > > undefined reference to `__efistub__GLOBAL_OFFSET_TABLE_' > > > aarch64-unknown-linux-gnueabi-ld: ./drivers/firmware/efi/libstub/lib.a(arm64- > > > stub.stub.o): relocation R_AARCH64_ADR_PREL_PG_HI21 against symbol > > > `__efistub__GLOBAL_OFFSET_TABLE_' which may bind externally can not be used > > > when making a shared object; recompile with -fPIC > > > /tmp/e2/build/linux-4.9.139/drivers/firmware/efi/libstub/arm64-stub.c:63: > > > (.init.text+0xc): dangerous relocation: unsupported relocation > > > /tmp/e2/build/linux-4.9.139/Makefile:1001: recipe for target 'vmlinux' failed > > > -make[1]: *** [vmlinux] Error 1 > > > > > > This is caused by commit 27b5ebf61818749b3568354c64a8ec2d9cd5ecca from > > > linux-4.9.y (which is 91ee5b21ee026c49e4e7483de69b55b8b47042be), reverting > > > this commit fixes the build. > > > > > > This happens with vanilla binutils 2.32 and gcc 8.3.0 as well as 9.1.0. See > > > the attached .config for reference. > > > > > > If you have questions or patches just ping me. > > > > Does Linus's latest tree also fail for you (or 5.1)? > > > > Nick, do we need to add another fix that is in mainline for this to work > > properly? > > > > For the record, this is an example of why I think backporting those > clang enablement patches is a bad idea. We can't actually build those > kernels with clang, can we? So what is the point? Yes "we" can. I do. Why can't you? And lots of devices rely on clang support for their kernels, as much as I would like to ignore them, I can't :( thanks, greg k-h