From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-lpp01m010-f49.google.com ([209.85.215.49]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1SSPkt-0001T2-8W for barebox@lists.infradead.org; Thu, 10 May 2012 09:34:20 +0000 Received: by laap9 with SMTP id p9so1127271laa.36 for ; Thu, 10 May 2012 02:33:49 -0700 (PDT) From: Antony Pavlov Date: Thu, 10 May 2012 13:33:42 +0400 Message-Id: <1336642422-23800-1-git-send-email-antonynpavlov@gmail.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: barebox-bounces@lists.infradead.org Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: [RFC] MIPS: initial modules support To: barebox@lists.infradead.org This code does not work correctly. insmod got unaligned access exception during apply_r_mips_32_rel Signed-off-by: Antony Pavlov --- arch/mips/Kconfig | 1 + arch/mips/include/asm/elf.h | 153 +++++++++++++++++++ arch/mips/include/asm/module.h | 17 ++- arch/mips/lib/Makefile | 1 + arch/mips/lib/module.c | 328 ++++++++++++++++++++++++++++++++++++++++ 5 files changed, 499 insertions(+), 1 deletion(-) create mode 100644 arch/mips/lib/module.c diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 50d5c67..55c5d3b 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -6,6 +6,7 @@ config MIPS select HAS_KALLSYMS select HAVE_CONFIGURABLE_MEMORY_LAYOUT select HAVE_CONFIGURABLE_TEXT_BASE + select HAS_MODULES default y config SYS_SUPPORTS_BIG_ENDIAN diff --git a/arch/mips/include/asm/elf.h b/arch/mips/include/asm/elf.h index b8b8219..9375508 100644 --- a/arch/mips/include/asm/elf.h +++ b/arch/mips/include/asm/elf.h @@ -15,6 +15,159 @@ #ifndef _ASM_MIPS_ELF_H #define _ASM_MIPS_ELF_H +/* ELF header e_flags defines. */ +/* MIPS architecture level. */ +#define EF_MIPS_ARCH_1 0x00000000 /* -mips1 code. */ +#define EF_MIPS_ARCH_2 0x10000000 /* -mips2 code. */ +#define EF_MIPS_ARCH_3 0x20000000 /* -mips3 code. */ +#define EF_MIPS_ARCH_4 0x30000000 /* -mips4 code. */ +#define EF_MIPS_ARCH_5 0x40000000 /* -mips5 code. */ +#define EF_MIPS_ARCH_32 0x50000000 /* MIPS32 code. */ +#define EF_MIPS_ARCH_64 0x60000000 /* MIPS64 code. */ +#define EF_MIPS_ARCH_32R2 0x70000000 /* MIPS32 R2 code. */ +#define EF_MIPS_ARCH_64R2 0x80000000 /* MIPS64 R2 code. */ + +/* The ABI of a file. */ +#define EF_MIPS_ABI_O32 0x00001000 /* O32 ABI. */ +#define EF_MIPS_ABI_O64 0x00002000 /* O32 extended for 64 bit. */ + +#define PT_MIPS_REGINFO 0x70000000 +#define PT_MIPS_RTPROC 0x70000001 +#define PT_MIPS_OPTIONS 0x70000002 + +/* Flags in the e_flags field of the header */ +#define EF_MIPS_NOREORDER 0x00000001 +#define EF_MIPS_PIC 0x00000002 +#define EF_MIPS_CPIC 0x00000004 +#define EF_MIPS_ABI2 0x00000020 +#define EF_MIPS_OPTIONS_FIRST 0x00000080 +#define EF_MIPS_32BITMODE 0x00000100 +#define EF_MIPS_ABI 0x0000f000 +#define EF_MIPS_ARCH 0xf0000000 + +#define DT_MIPS_RLD_VERSION 0x70000001 +#define DT_MIPS_TIME_STAMP 0x70000002 +#define DT_MIPS_ICHECKSUM 0x70000003 +#define DT_MIPS_IVERSION 0x70000004 +#define DT_MIPS_FLAGS 0x70000005 + #define RHF_NONE 0x00000000 + #define RHF_HARDWAY 0x00000001 + #define RHF_NOTPOT 0x00000002 + #define RHF_SGI_ONLY 0x00000010 +#define DT_MIPS_BASE_ADDRESS 0x70000006 +#define DT_MIPS_CONFLICT 0x70000008 +#define DT_MIPS_LIBLIST 0x70000009 +#define DT_MIPS_LOCAL_GOTNO 0x7000000a +#define DT_MIPS_CONFLICTNO 0x7000000b +#define DT_MIPS_LIBLISTNO 0x70000010 +#define DT_MIPS_SYMTABNO 0x70000011 +#define DT_MIPS_UNREFEXTNO 0x70000012 +#define DT_MIPS_GOTSYM 0x70000013 +#define DT_MIPS_HIPAGENO 0x70000014 +#define DT_MIPS_RLD_MAP 0x70000016 + +#define R_MIPS_NONE 0 +#define R_MIPS_16 1 +#define R_MIPS_32 2 +#define R_MIPS_REL32 3 +#define R_MIPS_26 4 +#define R_MIPS_HI16 5 +#define R_MIPS_LO16 6 +#define R_MIPS_GPREL16 7 +#define R_MIPS_LITERAL 8 +#define R_MIPS_GOT16 9 +#define R_MIPS_PC16 10 +#define R_MIPS_CALL16 11 +#define R_MIPS_GPREL32 12 +/* The remaining relocs are defined on Irix, although they are not + in the MIPS ELF ABI. */ +#define R_MIPS_UNUSED1 13 +#define R_MIPS_UNUSED2 14 +#define R_MIPS_UNUSED3 15 +#define R_MIPS_SHIFT5 16 +#define R_MIPS_SHIFT6 17 +#define R_MIPS_64 18 +#define R_MIPS_GOT_DISP 19 +#define R_MIPS_GOT_PAGE 20 +#define R_MIPS_GOT_OFST 21 +/* + * The following two relocation types are specified in the MIPS ABI + * conformance guide version 1.2 but not yet in the psABI. + */ +#define R_MIPS_GOTHI16 22 +#define R_MIPS_GOTLO16 23 +#define R_MIPS_SUB 24 +#define R_MIPS_INSERT_A 25 +#define R_MIPS_INSERT_B 26 +#define R_MIPS_DELETE 27 +#define R_MIPS_HIGHER 28 +#define R_MIPS_HIGHEST 29 +/* + * The following two relocation types are specified in the MIPS ABI + * conformance guide version 1.2 but not yet in the psABI. + */ +#define R_MIPS_CALLHI16 30 +#define R_MIPS_CALLLO16 31 +/* + * This range is reserved for vendor specific relocations. + */ +#define R_MIPS_LOVENDOR 100 +#define R_MIPS_HIVENDOR 127 + +#define SHN_MIPS_ACCOMON 0xff00 /* Allocated common symbols */ +#define SHN_MIPS_TEXT 0xff01 /* Allocated test symbols. */ +#define SHN_MIPS_DATA 0xff02 /* Allocated data symbols. */ +#define SHN_MIPS_SCOMMON 0xff03 /* Small common symbols */ +#define SHN_MIPS_SUNDEFINED 0xff04 /* Small undefined symbols */ + +#define SHT_MIPS_LIST 0x70000000 +#define SHT_MIPS_CONFLICT 0x70000002 +#define SHT_MIPS_GPTAB 0x70000003 +#define SHT_MIPS_UCODE 0x70000004 +#define SHT_MIPS_DEBUG 0x70000005 +#define SHT_MIPS_REGINFO 0x70000006 +#define SHT_MIPS_PACKAGE 0x70000007 +#define SHT_MIPS_PACKSYM 0x70000008 +#define SHT_MIPS_RELD 0x70000009 +#define SHT_MIPS_IFACE 0x7000000b +#define SHT_MIPS_CONTENT 0x7000000c +#define SHT_MIPS_OPTIONS 0x7000000d +#define SHT_MIPS_SHDR 0x70000010 +#define SHT_MIPS_FDESC 0x70000011 +#define SHT_MIPS_EXTSYM 0x70000012 +#define SHT_MIPS_DENSE 0x70000013 +#define SHT_MIPS_PDESC 0x70000014 +#define SHT_MIPS_LOCSYM 0x70000015 +#define SHT_MIPS_AUXSYM 0x70000016 +#define SHT_MIPS_OPTSYM 0x70000017 +#define SHT_MIPS_LOCSTR 0x70000018 +#define SHT_MIPS_LINE 0x70000019 +#define SHT_MIPS_RFDESC 0x7000001a +#define SHT_MIPS_DELTASYM 0x7000001b +#define SHT_MIPS_DELTAINST 0x7000001c +#define SHT_MIPS_DELTACLASS 0x7000001d +#define SHT_MIPS_DWARF 0x7000001e +#define SHT_MIPS_DELTADECL 0x7000001f +#define SHT_MIPS_SYMBOL_LIB 0x70000020 +#define SHT_MIPS_EVENTS 0x70000021 +#define SHT_MIPS_TRANSLATE 0x70000022 +#define SHT_MIPS_PIXIE 0x70000023 +#define SHT_MIPS_XLATE 0x70000024 +#define SHT_MIPS_XLATE_DEBUG 0x70000025 +#define SHT_MIPS_WHIRL 0x70000026 +#define SHT_MIPS_EH_REGION 0x70000027 +#define SHT_MIPS_XLATE_OLD 0x70000028 +#define SHT_MIPS_PDR_EXCEPTION 0x70000029 + +#define SHF_MIPS_GPREL 0x10000000 +#define SHF_MIPS_MERGE 0x20000000 +#define SHF_MIPS_ADDR 0x40000000 +#define SHF_MIPS_STRING 0x80000000 +#define SHF_MIPS_NOSTRIP 0x08000000 +#define SHF_MIPS_LOCAL 0x04000000 +#define SHF_MIPS_NAMES 0x02000000 +#define SHF_MIPS_NODUPES 0x01000000 + #ifndef ELF_ARCH #ifdef CONFIG_32BIT diff --git a/arch/mips/include/asm/module.h b/arch/mips/include/asm/module.h index 3046220..d423ced 100644 --- a/arch/mips/include/asm/module.h +++ b/arch/mips/include/asm/module.h @@ -19,6 +19,21 @@ #ifndef _ASM_MIPS_MODULE_H_ #define _ASM_MIPS_MODULE_H_ -/* nothing special yet */ +struct mod_arch_specific +{ +}; + +#ifdef CONFIG_32BIT +#define Elf_Shdr Elf32_Shdr +#define Elf_Sym Elf32_Sym +#define Elf_Ehdr Elf32_Ehdr +#define Elf_Addr Elf32_Addr + +#define Elf_Mips_Rel Elf32_Rel +#define Elf_Mips_Rela Elf32_Rela + +#define ELF_MIPS_R_SYM(rel) ELF32_R_SYM(rel.r_info) +#define ELF_MIPS_R_TYPE(rel) ELF32_R_TYPE(rel.r_info) +#endif #endif /* _ASM_MIPS_MODULE_H_ */ diff --git a/arch/mips/lib/Makefile b/arch/mips/lib/Makefile index 45fe920..8a043a6 100644 --- a/arch/mips/lib/Makefile +++ b/arch/mips/lib/Makefile @@ -6,3 +6,4 @@ obj-y += ashrdi3.o obj-y += memory.o obj-$(CONFIG_CMD_MIPS_CPUINFO) += cpuinfo.o +obj-$(CONFIG_MODULES) += module.o diff --git a/arch/mips/lib/module.c b/arch/mips/lib/module.c new file mode 100644 index 0000000..924d138 --- /dev/null +++ b/arch/mips/lib/module.c @@ -0,0 +1,328 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * Copyright (C) 2001 Rusty Russell. + * Copyright (C) 2003, 2004 Ralf Baechle (ralf@linux-mips.org) + * Copyright (C) 2005 Thiemo Seufer + */ + +#undef DEBUG +#define DEBUG + +#include +#include +#include +#include +#include +#include +#include + +struct mips_hi16 { + struct mips_hi16 *next; + Elf_Addr *addr; + Elf_Addr value; +}; + +static struct mips_hi16 *mips_hi16_list; + +static int apply_r_mips_none(struct module *me, u32 *location, Elf_Addr v) +{ + return 0; +} + +static int apply_r_mips_32_rel(struct module *me, u32 *location, Elf_Addr v) +{ + pr_debug("apply_r_mips_32_rel: locatio = %p, v = %08x\n", location, v); + + *location += v; + + return 0; +} + +static int apply_r_mips_32_rela(struct module *me, u32 *location, Elf_Addr v) +{ + *location = v; + + return 0; +} + +static int apply_r_mips_26_rel(struct module *me, u32 *location, Elf_Addr v) +{ + if (v % 4) { + pr_err("module %s: dangerous R_MIPS_26 REL relocation\n", + me->name); + return -ENOEXEC; + } + + if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) { + printk(KERN_ERR + "module %s: relocation overflow\n", + me->name); + return -ENOEXEC; + } + + *location = (*location & ~0x03ffffff) | + ((*location + (v >> 2)) & 0x03ffffff); + + return 0; +} + +static int apply_r_mips_26_rela(struct module *me, u32 *location, Elf_Addr v) +{ + if (v % 4) { + pr_err("module %s: dangerous R_MIPS_26 RELArelocation\n", + me->name); + return -ENOEXEC; + } + + if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) { + printk(KERN_ERR + "module %s: relocation overflow\n", + me->name); + return -ENOEXEC; + } + + *location = (*location & ~0x03ffffff) | ((v >> 2) & 0x03ffffff); + + return 0; +} + +static int apply_r_mips_hi16_rel(struct module *me, u32 *location, Elf_Addr v) +{ + struct mips_hi16 *n; + + /* + * We cannot relocate this one now because we don't know the value of + * the carry we need to add. Save the information, and let LO16 do the + * actual relocation. + */ + n = kmalloc(sizeof *n, GFP_KERNEL); + if (!n) + return -ENOMEM; + + n->addr = (Elf_Addr *)location; + n->value = v; + n->next = mips_hi16_list; + mips_hi16_list = n; + + return 0; +} + +static int apply_r_mips_hi16_rela(struct module *me, u32 *location, Elf_Addr v) +{ + *location = (*location & 0xffff0000) | + ((((long long) v + 0x8000LL) >> 16) & 0xffff); + + return 0; +} + +static int apply_r_mips_lo16_rel(struct module *me, u32 *location, Elf_Addr v) +{ + unsigned long insnlo = *location; + Elf_Addr val, vallo; + + /* Sign extend the addend we extract from the lo insn. */ + vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000; + + if (mips_hi16_list != NULL) { + struct mips_hi16 *l; + + l = mips_hi16_list; + while (l != NULL) { + struct mips_hi16 *next; + unsigned long insn; + + /* + * The value for the HI16 had best be the same. + */ + if (v != l->value) + goto out_danger; + + /* + * Do the HI16 relocation. Note that we actually don't + * need to know anything about the LO16 itself, except + * where to find the low 16 bits of the addend needed + * by the LO16. + */ + insn = *l->addr; + val = ((insn & 0xffff) << 16) + vallo; + val += v; + + /* + * Account for the sign extension that will happen in + * the low bits. + */ + val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff; + + insn = (insn & ~0xffff) | val; + *l->addr = insn; + + next = l->next; + kfree(l); + l = next; + } + + mips_hi16_list = NULL; + } + + /* + * Ok, we're done with the HI16 relocs. Now deal with the LO16. + */ + val = v + vallo; + insnlo = (insnlo & ~0xffff) | (val & 0xffff); + *location = insnlo; + + return 0; + +out_danger: + pr_err("module %s: dangerous R_MIPS_LO16 REL relocation\n", me->name); + + return -ENOEXEC; +} + +static int apply_r_mips_lo16_rela(struct module *me, u32 *location, Elf_Addr v) +{ + *location = (*location & 0xffff0000) | (v & 0xffff); + + return 0; +} + +static int apply_r_mips_64_rela(struct module *me, u32 *location, Elf_Addr v) +{ + *(Elf_Addr *)location = v; + + return 0; +} + +static int apply_r_mips_higher_rela(struct module *me, u32 *location, + Elf_Addr v) +{ + *location = (*location & 0xffff0000) | + ((((long long) v + 0x80008000LL) >> 32) & 0xffff); + + return 0; +} + +static int apply_r_mips_highest_rela(struct module *me, u32 *location, + Elf_Addr v) +{ + *location = (*location & 0xffff0000) | + ((((long long) v + 0x800080008000LL) >> 48) & 0xffff); + + return 0; +} + +static int (*reloc_handlers_rel[]) (struct module *me, u32 *location, + Elf_Addr v) = { + [R_MIPS_NONE] = apply_r_mips_none, + [R_MIPS_32] = apply_r_mips_32_rel, + [R_MIPS_26] = apply_r_mips_26_rel, + [R_MIPS_HI16] = apply_r_mips_hi16_rel, + [R_MIPS_LO16] = apply_r_mips_lo16_rel +}; + +static int (*reloc_handlers_rela[]) (struct module *me, u32 *location, + Elf_Addr v) = { + [R_MIPS_NONE] = apply_r_mips_none, + [R_MIPS_32] = apply_r_mips_32_rela, + [R_MIPS_26] = apply_r_mips_26_rela, + [R_MIPS_HI16] = apply_r_mips_hi16_rela, + [R_MIPS_LO16] = apply_r_mips_lo16_rela, + [R_MIPS_64] = apply_r_mips_64_rela, + [R_MIPS_HIGHER] = apply_r_mips_higher_rela, + [R_MIPS_HIGHEST] = apply_r_mips_highest_rela +}; + +int apply_relocate(Elf_Shdr *sechdrs, const char *strtab, + unsigned int symindex, unsigned int relsec, + struct module *me) +{ + Elf_Mips_Rel *rel = (void *) sechdrs[relsec].sh_addr; + Elf_Sym *sym; + u32 *location; + unsigned int i; + Elf_Addr v; + int res; + + pr_debug("Applying relocate section %u to %u\n", relsec, + sechdrs[relsec].sh_info); + + for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { + /* This is where to make the change */ + location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr + + rel[i].r_offset; + /* This is the symbol it is referring to */ + sym = (Elf_Sym *)sechdrs[symindex].sh_addr + + ELF_MIPS_R_SYM(rel[i]); + if (IS_ERR_VALUE(sym->st_value)) { + /* Ignore unresolved weak symbol */ + if (ELF_ST_BIND(sym->st_info) == STB_WEAK) + continue; + printk(KERN_WARNING "%s: Unknown symbol %s\n", + me->name, strtab + sym->st_name); + return -ENOENT; + } + + v = sym->st_value; + + printk(KERN_ERR "%s: location=%p, v=%08x\n", + me->name, location, v); + res = reloc_handlers_rel[ELF_MIPS_R_TYPE(rel[i])](me, location, v); + if (res) + return res; + } + + return 0; +} + +int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, + unsigned int symindex, unsigned int relsec, + struct module *me) +{ + Elf_Mips_Rela *rel = (void *) sechdrs[relsec].sh_addr; + Elf_Sym *sym; + u32 *location; + unsigned int i; + Elf_Addr v; + int res; + + pr_debug("Applying relocate section %u to %u\n", relsec, + sechdrs[relsec].sh_info); + + for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { + /* This is where to make the change */ + location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr + + rel[i].r_offset; + /* This is the symbol it is referring to */ + sym = (Elf_Sym *)sechdrs[symindex].sh_addr + + ELF_MIPS_R_SYM(rel[i]); + if (IS_ERR_VALUE(sym->st_value)) { + /* Ignore unresolved weak symbol */ + if (ELF_ST_BIND(sym->st_info) == STB_WEAK) + continue; + printk(KERN_WARNING "%s: Unknown symbol %s\n", + me->name, strtab + sym->st_name); + return -ENOENT; + } + + v = sym->st_value + rel[i].r_addend; + + res = reloc_handlers_rela[ELF_MIPS_R_TYPE(rel[i])](me, location, v); + if (res) + return res; + } + + return 0; +} -- 1.7.10 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox