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-rw-r--r--arch/x86/tools/relocs.c783
1 files changed, 501 insertions, 282 deletions
diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c
index 79d67bd..590be10 100644
--- a/arch/x86/tools/relocs.c
+++ b/arch/x86/tools/relocs.c
@@ -1,43 +1,36 @@
-#include <stdio.h>
-#include <stdarg.h>
-#include <stdlib.h>
-#include <stdint.h>
-#include <string.h>
-#include <errno.h>
-#include <unistd.h>
-#include <elf.h>
-#include <byteswap.h>
-#define USE_BSD
-#include <endian.h>
-#include <regex.h>
-#include <tools/le_byteshift.h>
-
-static void die(char *fmt, ...);
-
-#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
-static Elf32_Ehdr ehdr;
-static unsigned long reloc_count, reloc_idx;
-static unsigned long *relocs;
-static unsigned long reloc16_count, reloc16_idx;
-static unsigned long *relocs16;
+/* This is included from relocs_32/64.c */
+
+#define ElfW(type) _ElfW(ELF_BITS, type)
+#define _ElfW(bits, type) __ElfW(bits, type)
+#define __ElfW(bits, type) Elf##bits##_##type
+
+#define Elf_Addr ElfW(Addr)
+#define Elf_Ehdr ElfW(Ehdr)
+#define Elf_Phdr ElfW(Phdr)
+#define Elf_Shdr ElfW(Shdr)
+#define Elf_Sym ElfW(Sym)
+
+static Elf_Ehdr ehdr;
+
+struct relocs {
+ uint32_t *offset;
+ unsigned long count;
+ unsigned long size;
+};
+
+static struct relocs relocs16;
+static struct relocs relocs32;
+static struct relocs relocs64;
struct section {
- Elf32_Shdr shdr;
+ Elf_Shdr shdr;
struct section *link;
- Elf32_Sym *symtab;
- Elf32_Rel *reltab;
+ Elf_Sym *symtab;
+ Elf_Rel *reltab;
char *strtab;
};
static struct section *secs;
-enum symtype {
- S_ABS,
- S_REL,
- S_SEG,
- S_LIN,
- S_NSYMTYPES
-};
-
static const char * const sym_regex_kernel[S_NSYMTYPES] = {
/*
* Following symbols have been audited. There values are constant and do
@@ -49,6 +42,9 @@ static const char * const sym_regex_kernel[S_NSYMTYPES] = {
"^(xen_irq_disable_direct_reloc$|"
"xen_save_fl_direct_reloc$|"
"VDSO|"
+#if ELF_BITS == 64
+ "__vvar_page|"
+#endif
"__crc_)",
/*
@@ -72,6 +68,11 @@ static const char * const sym_regex_kernel[S_NSYMTYPES] = {
"__end_rodata|"
"__initramfs_start|"
"(jiffies|jiffies_64)|"
+#if ELF_BITS == 64
+ "__per_cpu_load|"
+ "init_per_cpu__.*|"
+ "__end_rodata_hpage_align|"
+#endif
"_end)$"
};
@@ -132,15 +133,6 @@ static void regex_init(int use_real_mode)
}
}
-static void die(char *fmt, ...)
-{
- va_list ap;
- va_start(ap, fmt);
- vfprintf(stderr, fmt, ap);
- va_end(ap);
- exit(1);
-}
-
static const char *sym_type(unsigned type)
{
static const char *type_name[] = {
@@ -198,6 +190,24 @@ static const char *rel_type(unsigned type)
{
static const char *type_name[] = {
#define REL_TYPE(X) [X] = #X
+#if ELF_BITS == 64
+ REL_TYPE(R_X86_64_NONE),
+ REL_TYPE(R_X86_64_64),
+ REL_TYPE(R_X86_64_PC32),
+ REL_TYPE(R_X86_64_GOT32),
+ REL_TYPE(R_X86_64_PLT32),
+ REL_TYPE(R_X86_64_COPY),
+ REL_TYPE(R_X86_64_GLOB_DAT),
+ REL_TYPE(R_X86_64_JUMP_SLOT),
+ REL_TYPE(R_X86_64_RELATIVE),
+ REL_TYPE(R_X86_64_GOTPCREL),
+ REL_TYPE(R_X86_64_32),
+ REL_TYPE(R_X86_64_32S),
+ REL_TYPE(R_X86_64_16),
+ REL_TYPE(R_X86_64_PC16),
+ REL_TYPE(R_X86_64_8),
+ REL_TYPE(R_X86_64_PC8),
+#else
REL_TYPE(R_386_NONE),
REL_TYPE(R_386_32),
REL_TYPE(R_386_PC32),
@@ -213,6 +223,7 @@ static const char *rel_type(unsigned type)
REL_TYPE(R_386_PC8),
REL_TYPE(R_386_16),
REL_TYPE(R_386_PC16),
+#endif
#undef REL_TYPE
};
const char *name = "unknown type rel type name";
@@ -240,7 +251,7 @@ static const char *sec_name(unsigned shndx)
return name;
}
-static const char *sym_name(const char *sym_strtab, Elf32_Sym *sym)
+static const char *sym_name(const char *sym_strtab, Elf_Sym *sym)
{
const char *name;
name = "<noname>";
@@ -253,15 +264,42 @@ static const char *sym_name(const char *sym_strtab, Elf32_Sym *sym)
return name;
}
+static Elf_Sym *sym_lookup(const char *symname)
+{
+ int i;
+ for (i = 0; i < ehdr.e_shnum; i++) {
+ struct section *sec = &secs[i];
+ long nsyms;
+ char *strtab;
+ Elf_Sym *symtab;
+ Elf_Sym *sym;
+
+ if (sec->shdr.sh_type != SHT_SYMTAB)
+ continue;
+ nsyms = sec->shdr.sh_size/sizeof(Elf_Sym);
+ symtab = sec->symtab;
+ strtab = sec->link->strtab;
+
+ for (sym = symtab; --nsyms >= 0; sym++) {
+ if (!sym->st_name)
+ continue;
+ if (strcmp(symname, strtab + sym->st_name) == 0)
+ return sym;
+ }
+ }
+ return 0;
+}
#if BYTE_ORDER == LITTLE_ENDIAN
#define le16_to_cpu(val) (val)
#define le32_to_cpu(val) (val)
+#define le64_to_cpu(val) (val)
#endif
#if BYTE_ORDER == BIG_ENDIAN
#define le16_to_cpu(val) bswap_16(val)
#define le32_to_cpu(val) bswap_32(val)
+#define le64_to_cpu(val) bswap_64(val)
#endif
static uint16_t elf16_to_cpu(uint16_t val)
@@ -274,6 +312,23 @@ static uint32_t elf32_to_cpu(uint32_t val)
return le32_to_cpu(val);
}
+#define elf_half_to_cpu(x) elf16_to_cpu(x)
+#define elf_word_to_cpu(x) elf32_to_cpu(x)
+
+#if ELF_BITS == 64
+static uint64_t elf64_to_cpu(uint64_t val)
+{
+ return le64_to_cpu(val);
+}
+#define elf_addr_to_cpu(x) elf64_to_cpu(x)
+#define elf_off_to_cpu(x) elf64_to_cpu(x)
+#define elf_xword_to_cpu(x) elf64_to_cpu(x)
+#else
+#define elf_addr_to_cpu(x) elf32_to_cpu(x)
+#define elf_off_to_cpu(x) elf32_to_cpu(x)
+#define elf_xword_to_cpu(x) elf32_to_cpu(x)
+#endif
+
static void read_ehdr(FILE *fp)
{
if (fread(&ehdr, sizeof(ehdr), 1, fp) != 1) {
@@ -283,8 +338,8 @@ static void read_ehdr(FILE *fp)
if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0) {
die("No ELF magic\n");
}
- if (ehdr.e_ident[EI_CLASS] != ELFCLASS32) {
- die("Not a 32 bit executable\n");
+ if (ehdr.e_ident[EI_CLASS] != ELF_CLASS) {
+ die("Not a %d bit executable\n", ELF_BITS);
}
if (ehdr.e_ident[EI_DATA] != ELFDATA2LSB) {
die("Not a LSB ELF executable\n");
@@ -293,36 +348,36 @@ static void read_ehdr(FILE *fp)
die("Unknown ELF version\n");
}
/* Convert the fields to native endian */
- ehdr.e_type = elf16_to_cpu(ehdr.e_type);
- ehdr.e_machine = elf16_to_cpu(ehdr.e_machine);
- ehdr.e_version = elf32_to_cpu(ehdr.e_version);
- ehdr.e_entry = elf32_to_cpu(ehdr.e_entry);
- ehdr.e_phoff = elf32_to_cpu(ehdr.e_phoff);
- ehdr.e_shoff = elf32_to_cpu(ehdr.e_shoff);
- ehdr.e_flags = elf32_to_cpu(ehdr.e_flags);
- ehdr.e_ehsize = elf16_to_cpu(ehdr.e_ehsize);
- ehdr.e_phentsize = elf16_to_cpu(ehdr.e_phentsize);
- ehdr.e_phnum = elf16_to_cpu(ehdr.e_phnum);
- ehdr.e_shentsize = elf16_to_cpu(ehdr.e_shentsize);
- ehdr.e_shnum = elf16_to_cpu(ehdr.e_shnum);
- ehdr.e_shstrndx = elf16_to_cpu(ehdr.e_shstrndx);
+ ehdr.e_type = elf_half_to_cpu(ehdr.e_type);
+ ehdr.e_machine = elf_half_to_cpu(ehdr.e_machine);
+ ehdr.e_version = elf_word_to_cpu(ehdr.e_version);
+ ehdr.e_entry = elf_addr_to_cpu(ehdr.e_entry);
+ ehdr.e_phoff = elf_off_to_cpu(ehdr.e_phoff);
+ ehdr.e_shoff = elf_off_to_cpu(ehdr.e_shoff);
+ ehdr.e_flags = elf_word_to_cpu(ehdr.e_flags);
+ ehdr.e_ehsize = elf_half_to_cpu(ehdr.e_ehsize);
+ ehdr.e_phentsize = elf_half_to_cpu(ehdr.e_phentsize);
+ ehdr.e_phnum = elf_half_to_cpu(ehdr.e_phnum);
+ ehdr.e_shentsize = elf_half_to_cpu(ehdr.e_shentsize);
+ ehdr.e_shnum = elf_half_to_cpu(ehdr.e_shnum);
+ ehdr.e_shstrndx = elf_half_to_cpu(ehdr.e_shstrndx);
if ((ehdr.e_type != ET_EXEC) && (ehdr.e_type != ET_DYN)) {
die("Unsupported ELF header type\n");
}
- if (ehdr.e_machine != EM_386) {
- die("Not for x86\n");
+ if (ehdr.e_machine != ELF_MACHINE) {
+ die("Not for %s\n", ELF_MACHINE_NAME);
}
if (ehdr.e_version != EV_CURRENT) {
die("Unknown ELF version\n");
}
- if (ehdr.e_ehsize != sizeof(Elf32_Ehdr)) {
+ if (ehdr.e_ehsize != sizeof(Elf_Ehdr)) {
die("Bad Elf header size\n");
}
- if (ehdr.e_phentsize != sizeof(Elf32_Phdr)) {
+ if (ehdr.e_phentsize != sizeof(Elf_Phdr)) {
die("Bad program header entry\n");
}
- if (ehdr.e_shentsize != sizeof(Elf32_Shdr)) {
+ if (ehdr.e_shentsize != sizeof(Elf_Shdr)) {
die("Bad section header entry\n");
}
if (ehdr.e_shstrndx >= ehdr.e_shnum) {
@@ -333,7 +388,7 @@ static void read_ehdr(FILE *fp)
static void read_shdrs(FILE *fp)
{
int i;
- Elf32_Shdr shdr;
+ Elf_Shdr shdr;
secs = calloc(ehdr.e_shnum, sizeof(struct section));
if (!secs) {
@@ -349,16 +404,16 @@ static void read_shdrs(FILE *fp)
if (fread(&shdr, sizeof shdr, 1, fp) != 1)
die("Cannot read ELF section headers %d/%d: %s\n",
i, ehdr.e_shnum, strerror(errno));
- sec->shdr.sh_name = elf32_to_cpu(shdr.sh_name);
- sec->shdr.sh_type = elf32_to_cpu(shdr.sh_type);
- sec->shdr.sh_flags = elf32_to_cpu(shdr.sh_flags);
- sec->shdr.sh_addr = elf32_to_cpu(shdr.sh_addr);
- sec->shdr.sh_offset = elf32_to_cpu(shdr.sh_offset);
- sec->shdr.sh_size = elf32_to_cpu(shdr.sh_size);
- sec->shdr.sh_link = elf32_to_cpu(shdr.sh_link);
- sec->shdr.sh_info = elf32_to_cpu(shdr.sh_info);
- sec->shdr.sh_addralign = elf32_to_cpu(shdr.sh_addralign);
- sec->shdr.sh_entsize = elf32_to_cpu(shdr.sh_entsize);
+ sec->shdr.sh_name = elf_word_to_cpu(shdr.sh_name);
+ sec->shdr.sh_type = elf_word_to_cpu(shdr.sh_type);
+ sec->shdr.sh_flags = elf_xword_to_cpu(shdr.sh_flags);
+ sec->shdr.sh_addr = elf_addr_to_cpu(shdr.sh_addr);
+ sec->shdr.sh_offset = elf_off_to_cpu(shdr.sh_offset);
+ sec->shdr.sh_size = elf_xword_to_cpu(shdr.sh_size);
+ sec->shdr.sh_link = elf_word_to_cpu(shdr.sh_link);
+ sec->shdr.sh_info = elf_word_to_cpu(shdr.sh_info);
+ sec->shdr.sh_addralign = elf_xword_to_cpu(shdr.sh_addralign);
+ sec->shdr.sh_entsize = elf_xword_to_cpu(shdr.sh_entsize);
if (sec->shdr.sh_link < ehdr.e_shnum)
sec->link = &secs[sec->shdr.sh_link];
}
@@ -412,12 +467,12 @@ static void read_symtabs(FILE *fp)
die("Cannot read symbol table: %s\n",
strerror(errno));
}
- for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Sym); j++) {
- Elf32_Sym *sym = &sec->symtab[j];
- sym->st_name = elf32_to_cpu(sym->st_name);
- sym->st_value = elf32_to_cpu(sym->st_value);
- sym->st_size = elf32_to_cpu(sym->st_size);
- sym->st_shndx = elf16_to_cpu(sym->st_shndx);
+ for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Sym); j++) {
+ Elf_Sym *sym = &sec->symtab[j];
+ sym->st_name = elf_word_to_cpu(sym->st_name);
+ sym->st_value = elf_addr_to_cpu(sym->st_value);
+ sym->st_size = elf_xword_to_cpu(sym->st_size);
+ sym->st_shndx = elf_half_to_cpu(sym->st_shndx);
}
}
}
@@ -428,7 +483,7 @@ static void read_relocs(FILE *fp)
int i,j;
for (i = 0; i < ehdr.e_shnum; i++) {
struct section *sec = &secs[i];
- if (sec->shdr.sh_type != SHT_REL) {
+ if (sec->shdr.sh_type != SHT_REL_TYPE) {
continue;
}
sec->reltab = malloc(sec->shdr.sh_size);
@@ -445,10 +500,13 @@ static void read_relocs(FILE *fp)
die("Cannot read symbol table: %s\n",
strerror(errno));
}
- for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Rel); j++) {
- Elf32_Rel *rel = &sec->reltab[j];
- rel->r_offset = elf32_to_cpu(rel->r_offset);
- rel->r_info = elf32_to_cpu(rel->r_info);
+ for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Rel); j++) {
+ Elf_Rel *rel = &sec->reltab[j];
+ rel->r_offset = elf_addr_to_cpu(rel->r_offset);
+ rel->r_info = elf_xword_to_cpu(rel->r_info);
+#if (SHT_REL_TYPE == SHT_RELA)
+ rel->r_addend = elf_xword_to_cpu(rel->r_addend);
+#endif
}
}
}
@@ -457,6 +515,13 @@ static void read_relocs(FILE *fp)
static void print_absolute_symbols(void)
{
int i;
+ const char *format;
+
+ if (ELF_BITS == 64)
+ format = "%5d %016"PRIx64" %5"PRId64" %10s %10s %12s %s\n";
+ else
+ format = "%5d %08"PRIx32" %5"PRId32" %10s %10s %12s %s\n";
+
printf("Absolute symbols\n");
printf(" Num: Value Size Type Bind Visibility Name\n");
for (i = 0; i < ehdr.e_shnum; i++) {
@@ -468,19 +533,19 @@ static void print_absolute_symbols(void)
continue;
}
sym_strtab = sec->link->strtab;
- for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Sym); j++) {
- Elf32_Sym *sym;
+ for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Sym); j++) {
+ Elf_Sym *sym;
const char *name;
sym = &sec->symtab[j];
name = sym_name(sym_strtab, sym);
if (sym->st_shndx != SHN_ABS) {
continue;
}
- printf("%5d %08x %5d %10s %10s %12s %s\n",
+ printf(format,
j, sym->st_value, sym->st_size,
- sym_type(ELF32_ST_TYPE(sym->st_info)),
- sym_bind(ELF32_ST_BIND(sym->st_info)),
- sym_visibility(ELF32_ST_VISIBILITY(sym->st_other)),
+ sym_type(ELF_ST_TYPE(sym->st_info)),
+ sym_bind(ELF_ST_BIND(sym->st_info)),
+ sym_visibility(ELF_ST_VISIBILITY(sym->st_other)),
name);
}
}
@@ -490,14 +555,20 @@ static void print_absolute_symbols(void)
static void print_absolute_relocs(void)
{
int i, printed = 0;
+ const char *format;
+
+ if (ELF_BITS == 64)
+ format = "%016"PRIx64" %016"PRIx64" %10s %016"PRIx64" %s\n";
+ else
+ format = "%08"PRIx32" %08"PRIx32" %10s %08"PRIx32" %s\n";
for (i = 0; i < ehdr.e_shnum; i++) {
struct section *sec = &secs[i];
struct section *sec_applies, *sec_symtab;
char *sym_strtab;
- Elf32_Sym *sh_symtab;
+ Elf_Sym *sh_symtab;
int j;
- if (sec->shdr.sh_type != SHT_REL) {
+ if (sec->shdr.sh_type != SHT_REL_TYPE) {
continue;
}
sec_symtab = sec->link;
@@ -507,12 +578,12 @@ static void print_absolute_relocs(void)
}
sh_symtab = sec_symtab->symtab;
sym_strtab = sec_symtab->link->strtab;
- for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Rel); j++) {
- Elf32_Rel *rel;
- Elf32_Sym *sym;
+ for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Rel); j++) {
+ Elf_Rel *rel;
+ Elf_Sym *sym;
const char *name;
rel = &sec->reltab[j];
- sym = &sh_symtab[ELF32_R_SYM(rel->r_info)];
+ sym = &sh_symtab[ELF_R_SYM(rel->r_info)];
name = sym_name(sym_strtab, sym);
if (sym->st_shndx != SHN_ABS) {
continue;
@@ -542,10 +613,10 @@ static void print_absolute_relocs(void)
printed = 1;
}
- printf("%08x %08x %10s %08x %s\n",
+ printf(format,
rel->r_offset,
rel->r_info,
- rel_type(ELF32_R_TYPE(rel->r_info)),
+ rel_type(ELF_R_TYPE(rel->r_info)),
sym->st_value,
name);
}
@@ -555,19 +626,34 @@ static void print_absolute_relocs(void)
printf("\n");
}
-static void walk_relocs(void (*visit)(Elf32_Rel *rel, Elf32_Sym *sym),
- int use_real_mode)
+static void add_reloc(struct relocs *r, uint32_t offset)
+{
+ if (r->count == r->size) {
+ unsigned long newsize = r->size + 50000;
+ void *mem = realloc(r->offset, newsize * sizeof(r->offset[0]));
+
+ if (!mem)
+ die("realloc of %ld entries for relocs failed\n",
+ newsize);
+ r->offset = mem;
+ r->size = newsize;
+ }
+ r->offset[r->count++] = offset;
+}
+
+static void walk_relocs(int (*process)(struct section *sec, Elf_Rel *rel,
+ Elf_Sym *sym, const char *symname))
{
int i;
/* Walk through the relocations */
for (i = 0; i < ehdr.e_shnum; i++) {
char *sym_strtab;
- Elf32_Sym *sh_symtab;
+ Elf_Sym *sh_symtab;
struct section *sec_applies, *sec_symtab;
int j;
struct section *sec = &secs[i];
- if (sec->shdr.sh_type != SHT_REL) {
+ if (sec->shdr.sh_type != SHT_REL_TYPE) {
continue;
}
sec_symtab = sec->link;
@@ -577,101 +663,281 @@ static void walk_relocs(void (*visit)(Elf32_Rel *rel, Elf32_Sym *sym),
}
sh_symtab = sec_symtab->symtab;
sym_strtab = sec_symtab->link->strtab;
- for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Rel); j++) {
- Elf32_Rel *rel;
- Elf32_Sym *sym;
- unsigned r_type;
- const char *symname;
- int shn_abs;
+ for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Rel); j++) {
+ Elf_Rel *rel = &sec->reltab[j];
+ Elf_Sym *sym = &sh_symtab[ELF_R_SYM(rel->r_info)];
+ const char *symname = sym_name(sym_strtab, sym);
- rel = &sec->reltab[j];
- sym = &sh_symtab[ELF32_R_SYM(rel->r_info)];
- r_type = ELF32_R_TYPE(rel->r_info);
-
- shn_abs = sym->st_shndx == SHN_ABS;
-
- switch (r_type) {
- case R_386_NONE:
- case R_386_PC32:
- case R_386_PC16:
- case R_386_PC8:
- /*
- * NONE can be ignored and and PC relative
- * relocations don't need to be adjusted.
- */
- break;
+ process(sec, rel, sym, symname);
+ }
+ }
+}
- case R_386_16:
- symname = sym_name(sym_strtab, sym);
- if (!use_real_mode)
- goto bad;
- if (shn_abs) {
- if (is_reloc(S_ABS, symname))
- break;
- else if (!is_reloc(S_SEG, symname))
- goto bad;
- } else {
- if (is_reloc(S_LIN, symname))
- goto bad;
- else
- break;
- }
- visit(rel, sym);
- break;
+/*
+ * The .data..percpu section is a special case for x86_64 SMP kernels.
+ * It is used to initialize the actual per_cpu areas and to provide
+ * definitions for the per_cpu variables that correspond to their offsets
+ * within the percpu area. Since the values of all of the symbols need
+ * to be offsets from the start of the per_cpu area the virtual address
+ * (sh_addr) of .data..percpu is 0 in SMP kernels.
+ *
+ * This means that:
+ *
+ * Relocations that reference symbols in the per_cpu area do not
+ * need further relocation (since the value is an offset relative
+ * to the start of the per_cpu area that does not change).
+ *
+ * Relocations that apply to the per_cpu area need to have their
+ * offset adjusted by by the value of __per_cpu_load to make them
+ * point to the correct place in the loaded image (because the
+ * virtual address of .data..percpu is 0).
+ *
+ * For non SMP kernels .data..percpu is linked as part of the normal
+ * kernel data and does not require special treatment.
+ *
+ */
+static int per_cpu_shndx = -1;
+Elf_Addr per_cpu_load_addr;
- case R_386_32:
- symname = sym_name(sym_strtab, sym);
- if (shn_abs) {
- if (is_reloc(S_ABS, symname))
- break;
- else if (!is_reloc(S_REL, symname))
- goto bad;
- } else {
- if (use_real_mode &&
- !is_reloc(S_LIN, symname))
- break;
- }
- visit(rel, sym);
- break;
- default:
- die("Unsupported relocation type: %s (%d)\n",
- rel_type(r_type), r_type);
+static void percpu_init(void)
+{
+ int i;
+ for (i = 0; i < ehdr.e_shnum; i++) {
+ ElfW(Sym) *sym;
+ if (strcmp(sec_name(i), ".data..percpu"))
+ continue;
+
+ if (secs[i].shdr.sh_addr != 0) /* non SMP kernel */
+ return;
+
+ sym = sym_lookup("__per_cpu_load");
+ if (!sym)
+ die("can't find __per_cpu_load\n");
+
+ per_cpu_shndx = i;
+ per_cpu_load_addr = sym->st_value;
+ return;
+ }
+}
+
+#if ELF_BITS == 64
+
+/*
+ * Check to see if a symbol lies in the .data..percpu section.
+ * For some as yet not understood reason the "__init_begin"
+ * symbol which immediately preceeds the .data..percpu section
+ * also shows up as it it were part of it so we do an explict
+ * check for that symbol name and ignore it.
+ */
+static int is_percpu_sym(ElfW(Sym) *sym, const char *symname)
+{
+ return (sym->st_shndx == per_cpu_shndx) &&
+ strcmp(symname, "__init_begin");
+}
+
+
+static int do_reloc64(struct section *sec, Elf_Rel *rel, ElfW(Sym) *sym,
+ const char *symname)
+{
+ unsigned r_type = ELF64_R_TYPE(rel->r_info);
+ ElfW(Addr) offset = rel->r_offset;
+ int shn_abs = (sym->st_shndx == SHN_ABS) && !is_reloc(S_REL, symname);
+
+ if (sym->st_shndx == SHN_UNDEF)
+ return 0;
+
+ /*
+ * Adjust the offset if this reloc applies to the percpu section.
+ */
+ if (sec->shdr.sh_info == per_cpu_shndx)
+ offset += per_cpu_load_addr;
+
+ switch (r_type) {
+ case R_X86_64_NONE:
+ case R_X86_64_PC32:
+ /*
+ * NONE can be ignored and PC relative relocations don't
+ * need to be adjusted.
+ */
+ break;
+
+ case R_X86_64_32:
+ case R_X86_64_32S:
+ case R_X86_64_64:
+ /*
+ * References to the percpu area don't need to be adjusted.
+ */
+ if (is_percpu_sym(sym, symname))
+ break;
+
+ if (shn_abs) {
+ /*
+ * Whitelisted absolute symbols do not require
+ * relocation.
+ */
+ if (is_reloc(S_ABS, symname))
break;
- bad:
- symname = sym_name(sym_strtab, sym);
- die("Invalid %s %s relocation: %s\n",
- shn_abs ? "absolute" : "relative",
- rel_type(r_type), symname);
- }
+
+ die("Invalid absolute %s relocation: %s\n",
+ rel_type(r_type), symname);
+ break;
}
+
+ /*
+ * Relocation offsets for 64 bit kernels are output
+ * as 32 bits and sign extended back to 64 bits when
+ * the relocations are processed.
+ * Make sure that the offset will fit.
+ */
+ if ((int32_t)offset != (int64_t)offset)
+ die("Relocation offset doesn't fit in 32 bits\n");
+
+ if (r_type == R_X86_64_64)
+ add_reloc(&relocs64, offset);
+ else
+ add_reloc(&relocs32, offset);
+ break;
+
+ default:
+ die("Unsupported relocation type: %s (%d)\n",
+ rel_type(r_type), r_type);
+ break;
}
+
+ return 0;
}
-static void count_reloc(Elf32_Rel *rel, Elf32_Sym *sym)
+#else
+
+static int do_reloc32(struct section *sec, Elf_Rel *rel, Elf_Sym *sym,
+ const char *symname)
{
- if (ELF32_R_TYPE(rel->r_info) == R_386_16)
- reloc16_count++;
- else
- reloc_count++;
+ unsigned r_type = ELF32_R_TYPE(rel->r_info);
+ int shn_abs = (sym->st_shndx == SHN_ABS) && !is_reloc(S_REL, symname);
+
+ switch (r_type) {
+ case R_386_NONE:
+ case R_386_PC32:
+ case R_386_PC16:
+ case R_386_PC8:
+ /*
+ * NONE can be ignored and PC relative relocations don't
+ * need to be adjusted.
+ */
+ break;
+
+ case R_386_32:
+ if (shn_abs) {
+ /*
+ * Whitelisted absolute symbols do not require
+ * relocation.
+ */
+ if (is_reloc(S_ABS, symname))
+ break;
+
+ die("Invalid absolute %s relocation: %s\n",
+ rel_type(r_type), symname);
+ break;
+ }
+
+ add_reloc(&relocs32, rel->r_offset);
+ break;
+
+ default:
+ die("Unsupported relocation type: %s (%d)\n",
+ rel_type(r_type), r_type);
+ break;
+ }
+
+ return 0;
}
-static void collect_reloc(Elf32_Rel *rel, Elf32_Sym *sym)
+static int do_reloc_real(struct section *sec, Elf_Rel *rel, Elf_Sym *sym,
+ const char *symname)
{
- /* Remember the address that needs to be adjusted. */
- if (ELF32_R_TYPE(rel->r_info) == R_386_16)
- relocs16[reloc16_idx++] = rel->r_offset;
- else
- relocs[reloc_idx++] = rel->r_offset;
+ unsigned r_type = ELF32_R_TYPE(rel->r_info);
+ int shn_abs = (sym->st_shndx == SHN_ABS) && !is_reloc(S_REL, symname);
+
+ switch (r_type) {
+ case R_386_NONE:
+ case R_386_PC32:
+ case R_386_PC16:
+ case R_386_PC8:
+ /*
+ * NONE can be ignored and PC relative relocations don't
+ * need to be adjusted.
+ */
+ break;
+
+ case R_386_16:
+ if (shn_abs) {
+ /*
+ * Whitelisted absolute symbols do not require
+ * relocation.
+ */
+ if (is_reloc(S_ABS, symname))
+ break;
+
+ if (is_reloc(S_SEG, symname)) {
+ add_reloc(&relocs16, rel->r_offset);
+ break;
+ }
+ } else {
+ if (!is_reloc(S_LIN, symname))
+ break;
+ }
+ die("Invalid %s %s relocation: %s\n",
+ shn_abs ? "absolute" : "relative",
+ rel_type(r_type), symname);
+ break;
+
+ case R_386_32:
+ if (shn_abs) {
+ /*
+ * Whitelisted absolute symbols do not require
+ * relocation.
+ */
+ if (is_reloc(S_ABS, symname))
+ break;
+
+ if (is_reloc(S_REL, symname)) {
+ add_reloc(&relocs32, rel->r_offset);
+ break;
+ }
+ } else {
+ if (is_reloc(S_LIN, symname))
+ add_reloc(&relocs32, rel->r_offset);
+ break;
+ }
+ die("Invalid %s %s relocation: %s\n",
+ shn_abs ? "absolute" : "relative",
+ rel_type(r_type), symname);
+ break;
+
+ default:
+ die("Unsupported relocation type: %s (%d)\n",
+ rel_type(r_type), r_type);
+ break;
+ }
+
+ return 0;
}
+#endif
+
static int cmp_relocs(const void *va, const void *vb)
{
- const unsigned long *a, *b;
+ const uint32_t *a, *b;
a = va; b = vb;
return (*a == *b)? 0 : (*a > *b)? 1 : -1;
}
-static int write32(unsigned int v, FILE *f)
+static void sort_relocs(struct relocs *r)
+{
+ qsort(r->offset, r->count, sizeof(r->offset[0]), cmp_relocs);
+}
+
+static int write32(uint32_t v, FILE *f)
{
unsigned char buf[4];
@@ -679,33 +945,40 @@ static int write32(unsigned int v, FILE *f)
return fwrite(buf, 1, 4, f) == 4 ? 0 : -1;
}
+static int write32_as_text(uint32_t v, FILE *f)
+{
+ return fprintf(f, "\t.long 0x%08"PRIx32"\n", v) > 0 ? 0 : -1;
+}
+
static void emit_relocs(int as_text, int use_real_mode)
{
int i;
- /* Count how many relocations I have and allocate space for them. */
- reloc_count = 0;
- walk_relocs(count_reloc, use_real_mode);
- relocs = malloc(reloc_count * sizeof(relocs[0]));
- if (!relocs) {
- die("malloc of %d entries for relocs failed\n",
- reloc_count);
- }
+ int (*write_reloc)(uint32_t, FILE *) = write32;
+ int (*do_reloc)(struct section *sec, Elf_Rel *rel, Elf_Sym *sym,
+ const char *symname);
+
+#if ELF_BITS == 64
+ if (!use_real_mode)
+ do_reloc = do_reloc64;
+ else
+ die("--realmode not valid for a 64-bit ELF file");
+#else
+ if (!use_real_mode)
+ do_reloc = do_reloc32;
+ else
+ do_reloc = do_reloc_real;
+#endif
- relocs16 = malloc(reloc16_count * sizeof(relocs[0]));
- if (!relocs16) {
- die("malloc of %d entries for relocs16 failed\n",
- reloc16_count);
- }
/* Collect up the relocations */
- reloc_idx = 0;
- walk_relocs(collect_reloc, use_real_mode);
+ walk_relocs(do_reloc);
- if (reloc16_count && !use_real_mode)
+ if (relocs16.count && !use_real_mode)
die("Segment relocations found but --realmode not specified\n");
/* Order the relocations for more efficient processing */
- qsort(relocs, reloc_count, sizeof(relocs[0]), cmp_relocs);
- qsort(relocs16, reloc16_count, sizeof(relocs16[0]), cmp_relocs);
+ sort_relocs(&relocs16);
+ sort_relocs(&relocs32);
+ sort_relocs(&relocs64);
/* Print the relocations */
if (as_text) {
@@ -714,114 +987,60 @@ static void emit_relocs(int as_text, int use_real_mode)
*/
printf(".section \".data.reloc\",\"a\"\n");
printf(".balign 4\n");
- if (use_real_mode) {
- printf("\t.long %lu\n", reloc16_count);
- for (i = 0; i < reloc16_count; i++)
- printf("\t.long 0x%08lx\n", relocs16[i]);
- printf("\t.long %lu\n", reloc_count);
- for (i = 0; i < reloc_count; i++) {
- printf("\t.long 0x%08lx\n", relocs[i]);
- }
- } else {
- /* Print a stop */
- printf("\t.long 0x%08lx\n", (unsigned long)0);
- for (i = 0; i < reloc_count; i++) {
- printf("\t.long 0x%08lx\n", relocs[i]);
- }
- }
-
- printf("\n");
+ write_reloc = write32_as_text;
}
- else {
- if (use_real_mode) {
- write32(reloc16_count, stdout);
- for (i = 0; i < reloc16_count; i++)
- write32(relocs16[i], stdout);
- write32(reloc_count, stdout);
- /* Now print each relocation */
- for (i = 0; i < reloc_count; i++)
- write32(relocs[i], stdout);
- } else {
+ if (use_real_mode) {
+ write_reloc(relocs16.count, stdout);
+ for (i = 0; i < relocs16.count; i++)
+ write_reloc(relocs16.offset[i], stdout);
+
+ write_reloc(relocs32.count, stdout);
+ for (i = 0; i < relocs32.count; i++)
+ write_reloc(relocs32.offset[i], stdout);
+ } else {
+ if (ELF_BITS == 64) {
/* Print a stop */
- write32(0, stdout);
+ write_reloc(0, stdout);
/* Now print each relocation */
- for (i = 0; i < reloc_count; i++) {
- write32(relocs[i], stdout);
- }
+ for (i = 0; i < relocs64.count; i++)
+ write_reloc(relocs64.offset[i], stdout);
}
+
+ /* Print a stop */
+ write_reloc(0, stdout);
+
+ /* Now print each relocation */
+ for (i = 0; i < relocs32.count; i++)
+ write_reloc(relocs32.offset[i], stdout);
}
}
-static void usage(void)
-{
- die("relocs [--abs-syms|--abs-relocs|--text|--realmode] vmlinux\n");
-}
+#if ELF_BITS == 64
+# define process process_64
+#else
+# define process process_32
+#endif
-int main(int argc, char **argv)
+void process(FILE *fp, int use_real_mode, int as_text,
+ int show_absolute_syms, int show_absolute_relocs)
{
- int show_absolute_syms, show_absolute_relocs;
- int as_text, use_real_mode;
- const char *fname;
- FILE *fp;
- int i;
-
- show_absolute_syms = 0;
- show_absolute_relocs = 0;
- as_text = 0;
- use_real_mode = 0;
- fname = NULL;
- for (i = 1; i < argc; i++) {
- char *arg = argv[i];
- if (*arg == '-') {
- if (strcmp(arg, "--abs-syms") == 0) {
- show_absolute_syms = 1;
- continue;
- }
- if (strcmp(arg, "--abs-relocs") == 0) {
- show_absolute_relocs = 1;
- continue;
- }
- if (strcmp(arg, "--text") == 0) {
- as_text = 1;
- continue;
- }
- if (strcmp(arg, "--realmode") == 0) {
- use_real_mode = 1;
- continue;
- }
- }
- else if (!fname) {
- fname = arg;
- continue;
- }
- usage();
- }
- if (!fname) {
- usage();
- }
regex_init(use_real_mode);
- fp = fopen(fname, "r");
- if (!fp) {
- die("Cannot open %s: %s\n",
- fname, strerror(errno));
- }
read_ehdr(fp);
read_shdrs(fp);
read_strtabs(fp);
read_symtabs(fp);
read_relocs(fp);
+ if (ELF_BITS == 64)
+ percpu_init();
if (show_absolute_syms) {
print_absolute_symbols();
- goto out;
+ return;
}
if (show_absolute_relocs) {
print_absolute_relocs();
- goto out;
+ return;
}
emit_relocs(as_text, use_real_mode);
-out:
- fclose(fp);
- return 0;
}
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