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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 AFB69C433E0 for ; Fri, 15 Jan 2021 14:48:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 881B323877 for ; Fri, 15 Jan 2021 14:48:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732335AbhAOOrz (ORCPT ); Fri, 15 Jan 2021 09:47:55 -0500 Received: from elvis.franken.de ([193.175.24.41]:53938 "EHLO elvis.franken.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732175AbhAOOry (ORCPT ); Fri, 15 Jan 2021 09:47:54 -0500 Received: from uucp (helo=alpha) by elvis.franken.de with local-bsmtp (Exim 3.36 #1) id 1l0QNY-0006aU-02; Fri, 15 Jan 2021 15:47:08 +0100 Received: by alpha.franken.de (Postfix, from userid 1000) id CCB8EC057E; Fri, 15 Jan 2021 15:40:37 +0100 (CET) Date: Fri, 15 Jan 2021 15:40:37 +0100 From: Thomas Bogendoerfer To: Alexander Lobakin Cc: Arnd Bergmann , Nathan Chancellor , Nick Desaulniers , Huacai Chen , Pei Huang , Kees Cook , Fangrui Song , Jiaxun Yang , Ralf Baechle , Corey Minyard , linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, stable@vger.kernel.org, clang-built-linux@googlegroups.com Subject: Re: [PATCH v5 mips-next 0/9] MIPS: vmlinux.lds.S sections fixes & cleanup Message-ID: <20210115144037.GC15166@alpha.franken.de> References: <20210110115245.30762-1-alobakin@pm.me> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210110115245.30762-1-alobakin@pm.me> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Jan 10, 2021 at 11:53:50AM +0000, Alexander Lobakin wrote: > This series hunts the problems discovered after manual enabling of > ARCH_WANT_LD_ORPHAN_WARN. Notably: > - adds the missing PAGE_ALIGNED_DATA() section affecting VDSO > placement (marked for stable); > - stops blind catching of orphan text sections with .text.* > directive; > - properly stops .eh_frame section generation. > > Compile and runtime tested on MIPS32R2 CPS board with no issues > using two different toolkits: > - Binutils 2.35.1, GCC 10.2.1 (with Alpine patches); > - LLVM stack: 11.0.0 and from latest Git snapshot. > > Since v4 [3]: > - new: drop redundant .text.cps-vec creation and blind inclusion > of orphan text sections via .text.* directive in vmlinux.lds.S; > - don't assert SIZEOF(.rel.dyn) as it's reported that it may be not > empty on certain machines and compilers (Thomas); > - align GOT table like it's done for ARM64; > - new: catch UBSAN's "unnamed data" sections in generic definitions > when building with LD_DEAD_CODE_DATA_ELIMINATION; > - collect Reviewed-bys (Kees, Nathan). > > Since v3 [2]: > - fix the third patch as GNU stack emits .rel.dyn into VDSO for > some reason if .cfi_sections is specified. > > Since v2 [1]: > - stop discarding .eh_frame and just prevent it from generating > (Kees); > - drop redundant sections assertions (Fangrui); > - place GOT table in .text instead of asserting as it's not empty > when building with LLVM (Nathan); > - catch compound literals in generic definitions when building with > LD_DEAD_CODE_DATA_ELIMINATION (Kees); > - collect two Reviewed-bys (Kees). > > Since v1 [0]: > - catch .got entries too as LLD may produce it (Nathan); > - check for unwanted sections to be zero-sized instead of > discarding (Fangrui). > > [0] https://lore.kernel.org/linux-mips/20210104121729.46981-1-alobakin@pm.me > [1] https://lore.kernel.org/linux-mips/20210106200713.31840-1-alobakin@pm.me > [2] https://lore.kernel.org/linux-mips/20210107115120.281008-1-alobakin@pm.me > [3] https://lore.kernel.org/linux-mips/20210107123331.354075-1-alobakin@pm.me > > Alexander Lobakin (9): > MIPS: vmlinux.lds.S: add missing PAGE_ALIGNED_DATA() section > MIPS: CPS: don't create redundant .text.cps-vec section > MIPS: vmlinux.lds.S: add ".gnu.attributes" to DISCARDS > MIPS: properly stop .eh_frame generation > MIPS: vmlinux.lds.S: explicitly catch .rel.dyn symbols > MIPS: vmlinux.lds.S: explicitly declare .got table > vmlinux.lds.h: catch compound literals into data and BSS > vmlinux.lds.h: catch UBSAN's "unnamed data" into data > MIPS: select ARCH_WANT_LD_ORPHAN_WARN > > arch/mips/Kconfig | 1 + > arch/mips/include/asm/asm.h | 18 ++++++++++++++++++ > arch/mips/kernel/cps-vec.S | 1 - > arch/mips/kernel/vmlinux.lds.S | 11 +++++++++-- > include/asm-generic/vmlinux.lds.h | 6 +++--- > 5 files changed, 31 insertions(+), 6 deletions(-) applied to mips-next. Thoomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ]