From: Wu Zhangjin <wuzhangjin@xxxxxxxxx> MIPS64 has 'weird' Elf64_Rel.r_info[1,2], which must be used instead of the generic Elf64_Rel.r_info, otherwise, the C version of recordmcount will not work for "segmentation fault". ---- [1] http://techpubs.sgi.com/library/manuals/4000/007-4658-001/pdf/007-4658-001.pdf [2] arch/mips/include/asm/module.h Signed-off-by: John Reiser <jreiser@xxxxxxxxxxxx> Signed-off-by: Maciej W. Rozycki <macro@xxxxxxxxxxxxxx> Tested-by: Wu Zhangjin <wuzhangjin@xxxxxxxxx> --- scripts/recordmcount.c | 41 +++++++++++++++++++++++++++++++++++++++++ scripts/recordmcount.h | 34 ++++++++++++++++++++++++++++++---- 2 files changed, 71 insertions(+), 4 deletions(-) diff --git a/scripts/recordmcount.c b/scripts/recordmcount.c index 26e1271..2d32b9c 100644 --- a/scripts/recordmcount.c +++ b/scripts/recordmcount.c @@ -217,6 +217,39 @@ is_mcounted_section_name(char const *const txtname) #define RECORD_MCOUNT_64 #include "recordmcount.h" +/* 64-bit EM_MIPS has weird ELF64_Rela.r_info. + * http://techpubs.sgi.com/library/manuals/4000/007-4658-001/pdf/007-4658-001.pdf + * We interpret Table 29 Relocation Operation (Elf64_Rel, Elf64_Rela) [p.40] + * to imply the order of the members; the spec does not say so. + * typedef unsigned char Elf64_Byte; + * fails on MIPS64 because their <elf.h> already has it! + */ + +typedef uint8_t myElf64_Byte; /* Type for a 8-bit quantity. */ + +union mips_r_info { + Elf64_Xword r_info; + struct { + Elf64_Word r_sym; /* Symbol index. */ + myElf64_Byte r_ssym; /* Special symbol. */ + myElf64_Byte r_type3; /* Third relocation. */ + myElf64_Byte r_type2; /* Second relocation. */ + myElf64_Byte r_type; /* First relocation. */ + } r_mips; +}; + +static uint64_t MIPS64_r_sym(Elf64_Rel const *rp) +{ + return w(((union mips_r_info){ .r_info = rp->r_info }).r_mips.r_sym); +} + +static void MIPS64_r_info(Elf64_Rel *const rp, unsigned sym, unsigned type) +{ + rp->r_info = ((union mips_r_info){ + .r_mips = { .r_sym = w(sym), .r_type = type } + }).r_info; +} + static void do_file(char const *const fname) { @@ -268,6 +301,7 @@ do_file(char const *const fname) case EM_386: reltype = R_386_32; break; case EM_ARM: reltype = R_ARM_ABS32; break; case EM_IA_64: reltype = R_IA64_IMM64; gpfx = '_'; break; + case EM_MIPS: /* reltype: e_class */ gpfx = '_'; break; case EM_PPC: reltype = R_PPC_ADDR32; gpfx = '_'; break; case EM_PPC64: reltype = R_PPC64_ADDR64; gpfx = '_'; break; case EM_S390: /* reltype: e_class */ gpfx = '_'; break; @@ -291,6 +325,8 @@ do_file(char const *const fname) } if (EM_S390 == w2(ehdr->e_machine)) reltype = R_390_32; + if (EM_MIPS == w2(ehdr->e_machine)) + reltype = R_MIPS_32; do32(ehdr, fname, reltype); } break; case ELFCLASS64: { @@ -303,6 +339,11 @@ do_file(char const *const fname) } if (EM_S390 == w2(ghdr->e_machine)) reltype = R_390_64; + if (EM_MIPS == w2(ghdr->e_machine)) { + reltype = R_MIPS_64; + Elf64_r_sym = MIPS64_r_sym; + Elf64_r_info = MIPS64_r_info; + } do64(ghdr, fname, reltype); } break; } /* end switch */ diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h index 7f39d09..190fd18 100644 --- a/scripts/recordmcount.h +++ b/scripts/recordmcount.h @@ -31,8 +31,12 @@ #undef Elf_Rela #undef Elf_Sym #undef ELF_R_SYM +#undef Elf_r_sym #undef ELF_R_INFO +#undef Elf_r_info #undef ELF_ST_BIND +#undef fn_ELF_R_SYM +#undef fn_ELF_R_INFO #undef uint_t #undef _w #undef _align @@ -52,8 +56,12 @@ # define Elf_Rela Elf64_Rela # define Elf_Sym Elf64_Sym # define ELF_R_SYM ELF64_R_SYM +# define Elf_r_sym Elf64_r_sym # define ELF_R_INFO ELF64_R_INFO +# define Elf_r_info Elf64_r_info # define ELF_ST_BIND ELF64_ST_BIND +# define fn_ELF_R_SYM fn_ELF64_R_SYM +# define fn_ELF_R_INFO fn_ELF64_R_INFO # define uint_t uint64_t # define _w w8 # define _align 7u @@ -72,14 +80,32 @@ # define Elf_Rela Elf32_Rela # define Elf_Sym Elf32_Sym # define ELF_R_SYM ELF32_R_SYM +# define Elf_r_sym Elf32_r_sym # define ELF_R_INFO ELF32_R_INFO +# define Elf_r_info Elf32_r_info # define ELF_ST_BIND ELF32_ST_BIND +# define fn_ELF_R_SYM fn_ELF32_R_SYM +# define fn_ELF_R_INFO fn_ELF32_R_INFO # define uint_t uint32_t # define _w w # define _align 3u # define _size 4 #endif +/* Functions and pointers that 64-bit EM_MIPS can override. */ +static uint_t fn_ELF_R_SYM(Elf_Rel const *rp) +{ + return ELF_R_SYM(_w(rp->r_info)); +} +static uint_t (*Elf_r_sym)(Elf_Rel const *rp) = fn_ELF_R_SYM; + +static void fn_ELF_R_INFO(Elf_Rel *const rp, unsigned sym, unsigned type) +{ + rp->r_info = ELF_R_INFO(sym, type); +} +static void (*Elf_r_info)(Elf_Rel *const rp, unsigned sym, unsigned type) = fn_ELF_R_INFO; + + /* Append the new shstrtab, Elf_Shdr[], __mcount_loc and its relocations. */ static void append_func(Elf_Ehdr *const ehdr, Elf_Shdr *const shstr, @@ -197,22 +223,22 @@ static uint_t *sift_rel_mcount(uint_t *mlocp, for (t = nrel; t; --t) { if (!mcountsym) { Elf_Sym const *const symp = - &sym0[ELF_R_SYM(_w(relp->r_info))]; + &sym0[Elf_r_sym(relp)]; char const *symname = &str0[w(symp->st_name)]; if ('.' == symname[0]) ++symname; /* ppc64 hack */ if (0 == strcmp((('_' == gpfx) ? "_mcount" : "mcount"), symname)) - mcountsym = ELF_R_SYM(_w(relp->r_info)); + mcountsym = Elf_r_sym(relp); } - if (mcountsym == ELF_R_SYM(_w(relp->r_info))) { + if (mcountsym == Elf_r_sym(relp)) { uint_t const addend = _w(_w(relp->r_offset) - recval); mrelp->r_offset = _w(offbase + ((void *)mlocp - (void *)mloc0)); - mrelp->r_info = _w(ELF_R_INFO(recsym, reltype)); + Elf_r_info(mrelp, recsym, reltype); if (sizeof(Elf_Rela) == rel_entsize) { ((Elf_Rela *)mrelp)->r_addend = addend; *mlocp++ = 0; -- 1.7.1
