diff options
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/boot/compressed/relocs.c | 87 | ||||
| -rw-r--r-- | arch/x86/kernel/vmlinux.lds.S | 4 |
2 files changed, 60 insertions, 31 deletions
diff --git a/arch/x86/boot/compressed/relocs.c b/arch/x86/boot/compressed/relocs.c index bbeb0c3fbd9..89bbf4e4d05 100644 --- a/arch/x86/boot/compressed/relocs.c +++ b/arch/x86/boot/compressed/relocs.c @@ -9,6 +9,9 @@ #include <byteswap.h> #define USE_BSD #include <endian.h> +#include <regex.h> + +static void die(char *fmt, ...); #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) static Elf32_Ehdr ehdr; @@ -30,25 +33,47 @@ static struct section *secs; * the address for which it has been compiled. Don't warn user about * absolute relocations present w.r.t these symbols. */ -static const char* safe_abs_relocs[] = { - "xen_irq_disable_direct_reloc", - "xen_save_fl_direct_reloc", -}; +static const char abs_sym_regex[] = + "^(xen_irq_disable_direct_reloc$|" + "xen_save_fl_direct_reloc$|" + "VDSO|" + "__crc_)"; +static regex_t abs_sym_regex_c; +static int is_abs_reloc(const char *sym_name) +{ + return !regexec(&abs_sym_regex_c, sym_name, 0, NULL, 0); +} -static int is_safe_abs_reloc(const char* sym_name) +/* + * These symbols are known to be relative, even if the linker marks them + * as absolute (typically defined outside any section in the linker script.) + */ +static const char rel_sym_regex[] = + "^_end$"; +static regex_t rel_sym_regex_c; +static int is_rel_reloc(const char *sym_name) { - int i; + return !regexec(&rel_sym_regex_c, sym_name, 0, NULL, 0); +} - for (i = 0; i < ARRAY_SIZE(safe_abs_relocs); i++) { - if (!strcmp(sym_name, safe_abs_relocs[i])) - /* Match found */ - return 1; - } - if (strncmp(sym_name, "VDSO", 4) == 0) - return 1; - if (strncmp(sym_name, "__crc_", 6) == 0) - return 1; - return 0; +static void regex_init(void) +{ + char errbuf[128]; + int err; + + err = regcomp(&abs_sym_regex_c, abs_sym_regex, + REG_EXTENDED|REG_NOSUB); + if (err) { + regerror(err, &abs_sym_regex_c, errbuf, sizeof errbuf); + die("%s", errbuf); + } + + err = regcomp(&rel_sym_regex_c, rel_sym_regex, + REG_EXTENDED|REG_NOSUB); + if (err) { + regerror(err, &rel_sym_regex_c, errbuf, sizeof errbuf); + die("%s", errbuf); + } } static void die(char *fmt, ...) @@ -131,7 +156,7 @@ static const char *rel_type(unsigned type) #undef REL_TYPE }; const char *name = "unknown type rel type name"; - if (type < ARRAY_SIZE(type_name)) { + if (type < ARRAY_SIZE(type_name) && type_name[type]) { name = type_name[type]; } return name; @@ -448,7 +473,7 @@ static void print_absolute_relocs(void) * Before warning check if this absolute symbol * relocation is harmless. */ - if (is_safe_abs_reloc(name)) + if (is_abs_reloc(name) || is_rel_reloc(name)) continue; if (!printed) { @@ -501,21 +526,26 @@ static void walk_relocs(void (*visit)(Elf32_Rel *rel, Elf32_Sym *sym)) sym = &sh_symtab[ELF32_R_SYM(rel->r_info)]; r_type = ELF32_R_TYPE(rel->r_info); /* Don't visit relocations to absolute symbols */ - if (sym->st_shndx == SHN_ABS) { + if (sym->st_shndx == SHN_ABS && + !is_rel_reloc(sym_name(sym_strtab, sym))) { continue; } - if (r_type == R_386_NONE || r_type == R_386_PC32) { + switch (r_type) { + case R_386_NONE: + case R_386_PC32: /* * NONE can be ignored and and PC relative * relocations don't need to be adjusted. */ - } - else if (r_type == R_386_32) { + break; + case R_386_32: /* Visit relocations that need to be adjusted */ visit(rel, sym); - } - else { - die("Unsupported relocation type: %d\n", r_type); + break; + default: + die("Unsupported relocation type: %s (%d)\n", + rel_type(r_type), r_type); + break; } } } @@ -571,16 +601,15 @@ static void emit_relocs(int as_text) } else { unsigned char buf[4]; - buf[0] = buf[1] = buf[2] = buf[3] = 0; /* Print a stop */ - printf("%c%c%c%c", buf[0], buf[1], buf[2], buf[3]); + fwrite("\0\0\0\0", 4, 1, stdout); /* Now print each relocation */ for (i = 0; i < reloc_count; i++) { buf[0] = (relocs[i] >> 0) & 0xff; buf[1] = (relocs[i] >> 8) & 0xff; buf[2] = (relocs[i] >> 16) & 0xff; buf[3] = (relocs[i] >> 24) & 0xff; - printf("%c%c%c%c", buf[0], buf[1], buf[2], buf[3]); + fwrite(buf, 4, 1, stdout); } } } @@ -598,6 +627,8 @@ int main(int argc, char **argv) FILE *fp; int i; + regex_init(); + show_absolute_syms = 0; show_absolute_relocs = 0; as_text = 0; diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index f3f2104408d..f92a0da608c 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -319,9 +319,7 @@ SECTIONS __brk_limit = .; } - .end : AT(ADDR(.end) - LOAD_OFFSET) { - _end = .; - } + _end = .; STABS_DEBUG DWARF_DEBUG |