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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 D7523C4321A for ; Tue, 11 Jun 2019 09:57:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A49E0207E0 for ; Tue, 11 Jun 2019 09:57:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391417AbfFKJ5E (ORCPT ); Tue, 11 Jun 2019 05:57:04 -0400 Received: from foss.arm.com ([217.140.110.172]:56976 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727726AbfFKJ5D (ORCPT ); Tue, 11 Jun 2019 05:57:03 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 893EC337; Tue, 11 Jun 2019 02:57:02 -0700 (PDT) Received: from [10.1.29.141] (e121487-lin.cambridge.arm.com [10.1.29.141]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 796C63F73C; Tue, 11 Jun 2019 02:58:43 -0700 (PDT) Subject: Re: [PATCH 07/15] binfmt_flat: use __be32 for the on-disk format To: Christoph Hellwig , Greg Ungerer Cc: uclinux-h8-devel@lists.sourceforge.jp, linux-xtensa@linux-xtensa.org, Michal Simek , linux-c6x-dev@linux-c6x.org, linux-sh@vger.kernel.org, linux-kernel@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-riscv@lists.infradead.org, linux-arm-kernel@lists.infradead.org References: <20190610212015.9157-1-hch@lst.de> <20190610212015.9157-8-hch@lst.de> From: Vladimir Murzin Message-ID: <462a7406-19df-7910-4499-8f0acd52bc82@arm.com> Date: Tue, 11 Jun 2019 10:57:00 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.0 MIME-Version: 1.0 In-Reply-To: <20190610212015.9157-8-hch@lst.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/10/19 10:20 PM, Christoph Hellwig wrote: > So far binfmt_flat has onl been supported on 32-bit platforms, so the ^^^^ only > variable size of the fields didn't matter. But the upcoming RISC-V > nommu port supports 64-bit CPUs, and we now have a conflict between > the elf2flt creation tool that always uses 32-bit fields and the kernel > that uses (unsigned) long field. Switch to the userspace view as the > rest of the binfmt_flat format is completely architecture neutral, > and binfmt_flat isn't the right binary format for huge executables to > start with. > > While we're at it also ensure these fields are using __be types as > they big endian and are byteswapped when loaded. > > Signed-off-by: Christoph Hellwig > > wip ^^^ Unintended? > --- > include/linux/flat.h | 48 ++++++++++++++++++++++---------------------- > 1 file changed, 24 insertions(+), 24 deletions(-) With comment message fixed: Reviewed-by: Vladimir Murzin > > diff --git a/include/linux/flat.h b/include/linux/flat.h > index 21d901ba191b..59e892d5fadb 100644 > --- a/include/linux/flat.h > +++ b/include/linux/flat.h > @@ -24,26 +24,26 @@ > */ > > struct flat_hdr { > - char magic[4]; > - unsigned long rev; /* version (as above) */ > - unsigned long entry; /* Offset of first executable instruction > - with text segment from beginning of file */ > - unsigned long data_start; /* Offset of data segment from beginning of > - file */ > - unsigned long data_end; /* Offset of end of data segment > - from beginning of file */ > - unsigned long bss_end; /* Offset of end of bss segment from beginning > - of file */ > + char magic[4]; > + __be32 rev; /* version (as above) */ > + __be32 entry; /* Offset of first executable instruction > + with text segment from beginning of file */ > + __be32 data_start; /* Offset of data segment from beginning of > + file */ > + __be32 data_end; /* Offset of end of data segment from beginning > + of file */ > + __be32 bss_end; /* Offset of end of bss segment from beginning > + of file */ > > /* (It is assumed that data_end through bss_end forms the bss segment.) */ > > - unsigned long stack_size; /* Size of stack, in bytes */ > - unsigned long reloc_start; /* Offset of relocation records from > - beginning of file */ > - unsigned long reloc_count; /* Number of relocation records */ > - unsigned long flags; > - unsigned long build_date; /* When the program/library was built */ > - unsigned long filler[5]; /* Reservered, set to zero */ > + __be32 stack_size; /* Size of stack, in bytes */ > + __be32 reloc_start; /* Offset of relocation records from beginning of > + file */ > + __be32 reloc_count; /* Number of relocation records */ > + __be32 flags; > + __be32 build_date; /* When the program/library was built */ > + __u32 filler[5]; /* Reservered, set to zero */ > }; > > #define FLAT_FLAG_RAM 0x0001 /* load program entirely into RAM */ > @@ -67,19 +67,19 @@ struct flat_hdr { > #define OLD_FLAT_RELOC_TYPE_BSS 2 > > typedef union { > - unsigned long value; > + u32 value; > struct { > # if defined(mc68000) && !defined(CONFIG_COLDFIRE) > - signed long offset : 30; > - unsigned long type : 2; > + s32 offset : 30; > + u32 type : 2; > # define OLD_FLAT_FLAG_RAM 0x1 /* load program entirely into RAM */ > # elif defined(__BIG_ENDIAN_BITFIELD) > - unsigned long type : 2; > - signed long offset : 30; > + u32 type : 2; > + s32 offset : 30; > # define OLD_FLAT_FLAG_RAM 0x1 /* load program entirely into RAM */ > # elif defined(__LITTLE_ENDIAN_BITFIELD) > - signed long offset : 30; > - unsigned long type : 2; > + s32 offset : 30; > + u32 type : 2; > # define OLD_FLAT_FLAG_RAM 0x1 /* load program entirely into RAM */ > # else > # error "Unknown bitfield order for flat files." >