From patchwork Sat Oct 12 08:14:28 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: 282997 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 DF9102C0146 for ; Sat, 12 Oct 2013 19:19:20 +1100 (EST) Received: from localhost (localhost [127.0.0.1]) by theia.denx.de (Postfix) with ESMTP id 75F024A0FB; Sat, 12 Oct 2013 10:16:57 +0200 (CEST) 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 60W+WuJBgc2q; Sat, 12 Oct 2013 10:16:57 +0200 (CEST) Received: from theia.denx.de (localhost [127.0.0.1]) by theia.denx.de (Postfix) with ESMTP id CF0944A113; Sat, 12 Oct 2013 10:16:46 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by theia.denx.de (Postfix) with ESMTP id 07DFA4A081 for ; Sat, 12 Oct 2013 10:16:39 +0200 (CEST) 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 uN2hv9szZGkn for ; Sat, 12 Oct 2013 10:16:37 +0200 (CEST) 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 (app64.corpease.net [61.145.121.64]) by theia.denx.de (Postfix) with ESMTP id 95FA24A0FB for ; Sat, 12 Oct 2013 10:16:18 +0200 (CEST) Received: from localhost (unknown [220.202.152.17]) by app9 (Coremail) with SMTP id QAGowHCrXqr_BFlSMccNAA--.8244S3; Sat, 12 Oct 2013 16:14:56 +0800 (CST) From: fenghua@phytium.com.cn To: u-boot@lists.denx.de Date: Sat, 12 Oct 2013 16:14:28 +0800 Message-Id: <1381565674-6855-5-git-send-email-fenghua@phytium.com.cn> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1381565674-6855-4-git-send-email-fenghua@phytium.com.cn> References: <1381565674-6855-1-git-send-email-fenghua@phytium.com.cn> <1381565674-6855-2-git-send-email-fenghua@phytium.com.cn> <1381565674-6855-3-git-send-email-fenghua@phytium.com.cn> <1381565674-6855-4-git-send-email-fenghua@phytium.com.cn> X-CM-TRANSID: QAGowHCrXqr_BFlSMccNAA--.8244S3 X-Coremail-Antispam: 1UD129KBjvJXoW3XrW5Cw4kGr1DtF4DKw1fCrg_yoWfJr4kpF W3ZF1Yka95Jry7A3s3Xw1YgFySkws29F15Wry7Kr1kAF1fAFWvgrWIqFZ8JrykWr1xta15 ZrsFyFWjkF4rX3DanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUvGb4IE77IF4wAFF20E14v26r4j6ryUM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4 vEj48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Jr0_JF4l84ACjcxK6xIIjxv20xvEc7Cj xVAFwI0_Gr0_Cr1l84ACjcxK6I8E87Iv67AKxVWUJVW8JwA2z4x0Y4vEx4A2jsIEc7CjxV AFwI0_Gr0_Gr1UM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40E x7xfMcIj6xIIjxv20xvE14v26r126r1DMcIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x 0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7M4kE6xkI j40Ew7xC0wCY02Avz4vE14v_GFyl42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr 0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY 17CE14v26r126r1DMIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcV C0I7IYx2IY6xkF7I0E14v26r4j6F4UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY 6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa 73UjIFyTuYvj4RJUUUUUUUU X-Originating-IP: [220.202.152.17] X-CM-SenderInfo: pihqwxdxd61x51wl3zoofrzhdfq/ Cc: trini@ti.com, scottwood@freescale.com Subject: [U-Boot] [PATCH v14 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: David Feng 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. NOTE: Please make sure R_AARCH64_RELATIVE is defined at system include files or define it manually. Otherwise, the rela relocation will not apply. Signed-off-by: Scott Wood Signed-off-by: David Feng --- Makefile | 12 ++++ tools/Makefile | 6 ++ tools/relocate-rela.c | 185 +++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 203 insertions(+) create mode 100644 tools/relocate-rela.c diff --git a/Makefile b/Makefile index b09bfcc..5dd28a9 100644 --- a/Makefile +++ b/Makefile @@ -392,6 +392,17 @@ 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 @@ -431,6 +442,7 @@ $(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: $(obj)u-boot diff --git a/tools/Makefile b/tools/Makefile index c36cde2..a5eb85e 100644 --- a/tools/Makefile +++ b/tools/Makefile @@ -59,6 +59,7 @@ BIN_FILES-$(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..47afe0b --- /dev/null +++ b/tools/relocate-rela.c @@ -0,0 +1,185 @@ +/* + * 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 + +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; +}