From patchwork Fri Nov 15 03:45:53 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: fenghua@phytium.com.cn X-Patchwork-Id: 291436 X-Patchwork-Delegate: albert.aribaud@free.fr Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from theia.denx.de (theia.denx.de [85.214.87.163]) by ozlabs.org (Postfix) with ESMTP id 982382C00BC for ; Fri, 15 Nov 2013 14:47:58 +1100 (EST) Received: from localhost (localhost [127.0.0.1]) by theia.denx.de (Postfix) with ESMTP id 6564A4ADA4; Fri, 15 Nov 2013 04:47:36 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at theia.denx.de Received: from theia.denx.de ([127.0.0.1]) by localhost (theia.denx.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id JoHXN23qKiNe; Fri, 15 Nov 2013 04:47:36 +0100 (CET) Received: from theia.denx.de (localhost [127.0.0.1]) by theia.denx.de (Postfix) with ESMTP id 063974ADB5; Fri, 15 Nov 2013 04:47:27 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by theia.denx.de (Postfix) with ESMTP id C6F8D4ADB9 for ; Fri, 15 Nov 2013 04:47:23 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at theia.denx.de Received: from theia.denx.de ([127.0.0.1]) by localhost (theia.denx.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id JbuCWrxzlEpX for ; Fri, 15 Nov 2013 04:47:20 +0100 (CET) X-policyd-weight: NOT_IN_SBL_XBL_SPAMHAUS=-1.5 NOT_IN_SPAMCOP=-1.5 NOT_IN_BL_NJABL=-1.5 (only DNSBL check requested) Received: from mail.corpease.net (mail10.corpease.net [61.145.121.76]) by theia.denx.de (Postfix) with ESMTP id 59FE84AD7F for ; Fri, 15 Nov 2013 04:47:11 +0100 (CET) Received: from localhost (unknown [220.202.153.92]) by mail10.corpease.net (Coremail) with SMTP id TAGowJALPQcqmYVS6Bw2AA--.31400S3; Fri, 15 Nov 2013 11:46:52 +0800 (CST) From: fenghua@phytium.com.cn To: u-boot@lists.denx.de Date: Fri, 15 Nov 2013 11:45:53 +0800 Message-Id: <1384487159-43032-5-git-send-email-fenghua@phytium.com.cn> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1384487159-43032-4-git-send-email-fenghua@phytium.com.cn> References: <1384487159-43032-1-git-send-email-fenghua@phytium.com.cn> <1384487159-43032-2-git-send-email-fenghua@phytium.com.cn> <1384487159-43032-3-git-send-email-fenghua@phytium.com.cn> <1384487159-43032-4-git-send-email-fenghua@phytium.com.cn> X-CM-TRANSID: TAGowJALPQcqmYVS6Bw2AA--.31400S3 X-Coremail-Antispam: 1UD129KBjvJXoW3XrW5Cw4kGr1DtF4DKrW3Wrg_yoW3KFy5pF ZxZF1Yka95Jry7A3s3Jw1YgFySkws29F15WFy7Kr1kAF1fAFWvgrWIqFWDJrykWr1ftF45 ZrsFyFWjkF4rJ3DanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUdGb7IF0VCYb41lb7IF0VCFI7km07C26c804VAKzcIF0wAYjxAI 6xZILanIXVAFwwAYjxAI6IIYrVAFwwAYjsxI4VWxJwAYFVCjjxCrM7AC8VAFwI0_Gr0_Xr 1l1xkIjI8I6I8E6xAIw20EY4v20xvaj40_Wr0E3s1l1IIY67AEw4v_Jr0_Jr4l8cAvFVAK 0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVWUJVWUCwA2z4 x0Y4vE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwA2z4x0Y4vEx4A2jsIE14v26r1j6r4UM28E F7xvwVC2z280aVCY1x0267AKxVW8JVW8Jr1ln4vE4IxY62xKV4CY8xCE548m6r4UJryUGw AS0I0E0xvYzxvE52x082IY62kv0487Mc804VCqF7xvr2I5Mc02F40EFcxC0VAKzVAqx4xG 6I80ewAv7VC0I7IYx2IY67AKxVWUAVWUtwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFV Cjc4AY6r1j6r4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwAKzVCY 07xG64k0F24lc2xSY4AK67AK6r48MxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r 1j6r4UMxCIbVAxMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWl x4CE17CEb7AF67AKxVWUAVWUtwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r 1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwCI42IY6xAIw20EY4v20xvaj40_Jr0_ JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcS sGvfC2KfnxnUUI43ZEXa7x5xrUlUUUUUU== X-Originating-IP: [220.202.153.92] X-CM-SenderInfo: pihqwxdxd61x51wl3zoofrzhdfq/ Cc: trini@ti.com, scottwood@freescale.com Subject: [U-Boot] [PATCH v15 04/10] arm64: Add tool to statically apply RELA relocations X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.11 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: u-boot-bounces@lists.denx.de Errors-To: u-boot-bounces@lists.denx.de From: Scott Wood ARM64 uses the newer RELA-style relocations rather than the older REL. RELA relocations have an addend in the relocation struct, rather than expecting the loader to read a value from the location to be updated. While this is beneficial for ordinary program loading, it's problematic for U-Boot because the location to be updated starts out with zero, rather than a pre-relocation value. Since we need to be able to run C code before relocation, we need a tool to apply the relocations at build time. In theory this tool is applicable to other newer architectures (mainly 64-bit), but currently the only relocations it supports are for arm64, and it assumes a 64-bit little-endian target. If the latter limitation is ever to be changed, we'll need a way to tell the tool what format the image is in. Eventually this may be replaced by a tool that uses libelf or similar and operates directly on the ELF file. I've written some code for such an approach but libelf does not make it easy to poke addresses by memory address (rather than by section), and I was hesitant to write code to manually parse the program headers and do the update outside of libelf (or to iterate over sections) -- especially since it wouldn't get test coverage on things like binaries with multiple PT_LOAD segments. This should be good enough for now to let the manual relocation stuff be removed from the arm64 patches. Signed-off-by: Scott Wood Signed-off-by: David Feng --- Makefile | 12 ++++ tools/Makefile | 6 ++ tools/relocate-rela.c | 189 +++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 207 insertions(+) create mode 100644 tools/relocate-rela.c diff --git a/Makefile b/Makefile index 1f499c5..1dbe796 100644 --- a/Makefile +++ b/Makefile @@ -355,6 +355,17 @@ else BOARD_SIZE_CHECK = endif +# Statically apply RELA-style relocations (currently arm64 only) +ifneq ($(CONFIG_STATIC_RELA),) +# $(1) is u-boot ELF, $(2) is u-boot bin, $(3) is text base +DO_STATIC_RELA = \ + start=$$($(NM) $(1) | grep __rel_dyn_start | cut -f 1 -d ' '); \ + end=$$($(NM) $(1) | grep __rel_dyn_end | cut -f 1 -d ' '); \ + $(obj)tools/relocate-rela $(2) $(3) $$start $$end +else +DO_STATIC_RELA = +endif + # Always append ALL so that arch config.mk's can add custom ones ALL-y += $(obj)u-boot.srec $(obj)u-boot.bin $(obj)System.map @@ -397,6 +408,7 @@ $(obj)u-boot.srec: $(obj)u-boot $(obj)u-boot.bin: $(obj)u-boot $(OBJCOPY) ${OBJCFLAGS} -O binary $< $@ + $(call DO_STATIC_RELA,$<,$@,$(CONFIG_SYS_TEXT_BASE)) $(BOARD_SIZE_CHECK) $(obj)u-boot.ldr: $(obj)u-boot diff --git a/tools/Makefile b/tools/Makefile index 14d94e3..6d40398 100644 --- a/tools/Makefile +++ b/tools/Makefile @@ -59,6 +59,7 @@ BIN_FILES-$(CONFIG_NETCONSOLE) += ncb$(SFX) BIN_FILES-$(CONFIG_SHA1_CHECK_UB_IMG) += ubsha1$(SFX) BIN_FILES-$(CONFIG_KIRKWOOD) += kwboot$(SFX) BIN_FILES-y += proftool(SFX) +BIN_FILES-$(CONFIG_STATIC_RELA) += relocate-rela$(SFX) # Source files which exist outside the tools directory EXT_OBJ_FILES-$(CONFIG_BUILD_ENVCRC) += common/env_embedded.o @@ -84,6 +85,7 @@ NOPED_OBJ_FILES-y += os_support.o NOPED_OBJ_FILES-y += pblimage.o NOPED_OBJ_FILES-y += proftool.o NOPED_OBJ_FILES-y += ublimage.o +NOPED_OBJ_FILES-y += relocate-rela.o OBJ_FILES-$(CONFIG_BUILD_ENVCRC) += envcrc.o OBJ_FILES-$(CONFIG_CMD_LOADS) += img2srec.o OBJ_FILES-$(CONFIG_CMD_NET) += gen_eth_addr.o @@ -250,6 +252,10 @@ $(obj)kwboot$(SFX): $(obj)kwboot.o $(HOSTCC) $(HOSTCFLAGS) $(HOSTLDFLAGS) -o $@ $^ $(HOSTSTRIP) $@ +$(obj)relocate-rela$(SFX): $(obj)relocate-rela.o + $(HOSTCC) $(HOSTCFLAGS) $(HOSTLDFLAGS) -o $@ $^ + $(HOSTSTRIP) $@ + # Some of the tool objects need to be accessed from outside the tools directory $(obj)%.o: $(SRCTREE)/common/%.c $(HOSTCC) -g $(HOSTCFLAGS_NOPED) -c -o $@ $< diff --git a/tools/relocate-rela.c b/tools/relocate-rela.c new file mode 100644 index 0000000..93b4c39 --- /dev/null +++ b/tools/relocate-rela.c @@ -0,0 +1,189 @@ +/* + * Copyright 2013 Freescale Semiconductor, Inc. + * + * SPDX-License-Identifier: GPL-2.0+ BSD-2-Clause + * + * 64-bit and little-endian target only until we need to support a different + * arch that needs this. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#ifndef R_AARCH64_RELATIVE +#define R_AARCH64_RELATIVE 1027 +#endif + +static const bool debug_en; + +static void debug(const char *fmt, ...) +{ + va_list args; + + va_start(args, fmt); + if (debug_en) + vprintf(fmt, args); +} + +static bool supported_rela(Elf64_Rela *rela) +{ + uint64_t mask = 0xffffffffULL; /* would be different on 32-bit */ + uint32_t type = rela->r_info & mask; + + switch (type) { +#ifdef R_AARCH64_RELATIVE + case R_AARCH64_RELATIVE: + return true; +#endif + default: + fprintf(stderr, "warning: unsupported relocation type %" + PRIu32 " at %" PRIx64 "\n", + type, rela->r_offset); + + return false; + } +} + +static inline uint64_t swap64(uint64_t val) +{ + return ((val >> 56) & 0x00000000000000ffULL) | + ((val >> 40) & 0x000000000000ff00ULL) | + ((val >> 24) & 0x0000000000ff0000ULL) | + ((val >> 8) & 0x00000000ff000000ULL) | + ((val << 8) & 0x000000ff00000000ULL) | + ((val << 24) & 0x0000ff0000000000ULL) | + ((val << 40) & 0x00ff000000000000ULL) | + ((val << 56) & 0xff00000000000000ULL); +} + +#if __BYTE_ORDER == __LITTLE_ENDIAN +static inline uint64_t be64(uint64_t val) +{ + return swap64(val); +} + +static inline uint64_t le64(uint64_t val) +{ + return val; +} +#else +static inline uint64_t le64(uint64_t val) +{ + return swap64(val); +} + +static inline uint64_t be64(uint64_t val) +{ + return val; +} +#endif + +static bool read_num(const char *str, uint64_t *num) +{ + char *endptr; + *num = strtoull(str, &endptr, 16); + return str[0] && !endptr[0]; +} + +int main(int argc, char **argv) +{ + FILE *f; + int i, num; + uint64_t rela_start, rela_end, text_base; + + if (argc != 5) { + fprintf(stderr, "Statically apply ELF rela relocations\n"); + fprintf(stderr, "Usage: %s " \ + " \n", argv[0]); + fprintf(stderr, "All numbers in hex.\n"); + return 1; + } + + f = fopen(argv[1], "r+b"); + if (!f) { + fprintf(stderr, "%s: Cannot open %s: %s\n", + argv[0], argv[1], strerror(errno)); + return 2; + } + + if (!read_num(argv[2], &text_base) || + !read_num(argv[3], &rela_start) || + !read_num(argv[4], &rela_end)) { + fprintf(stderr, "%s: bad number\n", argv[0]); + return 3; + } + + if (rela_start > rela_end || rela_start < text_base || + (rela_end - rela_start) % 24) { + fprintf(stderr, "%s: bad rela bounds\n", argv[0]); + return 3; + } + + rela_start -= text_base; + rela_end -= text_base; + + num = (rela_end - rela_start) / sizeof(Elf64_Rela); + + for (i = 0; i < num; i++) { + Elf64_Rela rela, swrela; + uint64_t pos = rela_start + sizeof(Elf64_Rela) * i; + uint64_t addr; + + if (fseek(f, pos, SEEK_SET) < 0) { + fprintf(stderr, "%s: %s: seek to %" PRIx64 + " failed: %s\n", + argv[0], argv[1], pos, strerror(errno)); + } + + if (fread(&rela, sizeof(rela), 1, f) != 1) { + fprintf(stderr, "%s: %s: read rela failed at %" + PRIx64 "\n", + argv[0], argv[1], pos); + return 4; + } + + swrela.r_offset = le64(rela.r_offset); + swrela.r_info = le64(rela.r_info); + swrela.r_addend = le64(rela.r_addend); + + if (!supported_rela(&swrela)) + continue; + + debug("Rela %" PRIx64 " %" PRIu64 " %" PRIx64 "\n", + swrela.r_offset, swrela.r_info, swrela.r_addend); + + if (swrela.r_offset < text_base) { + fprintf(stderr, "%s: %s: bad rela at %" PRIx64 "\n", + argv[0], argv[1], pos); + return 4; + } + + addr = swrela.r_offset - text_base; + + if (fseek(f, addr, SEEK_SET) < 0) { + fprintf(stderr, "%s: %s: seek to %" + PRIx64 " failed: %s\n", + argv[0], argv[1], addr, strerror(errno)); + } + + if (fwrite(&rela.r_addend, sizeof(rela.r_addend), 1, f) != 1) { + fprintf(stderr, "%s: %s: write failed at %" PRIx64 "\n", + argv[0], argv[1], addr); + return 4; + } + } + + if (fclose(f) < 0) { + fprintf(stderr, "%s: %s: close failed: %s\n", + argv[0], argv[1], strerror(errno)); + return 4; + } + + return 0; +}