kbuild: make better section mismatch reports on i386, arm and mips

On i386, ARM and MIPS, warn_sec_mismatch() sometimes fails to show usefull symbol name. This is because empty 'refsym' due to 0 r_addend value. This patch is to adjust r_addend value, consulting with apply_relocate() routine in kernel code. Without this patch: MODPOST vmlinux WARNING: init/built-in.o - Section mismatch: reference to .init.text: from .text between 'rest_init' (at offset 0xf4) and 'try_name' WARNING: mm/built-in.o - Section mismatch: reference to .init.text: from .text between 'kmem_cache_create' (at offset 0x18a39) and 'cache_reap' WARNING: mm/built-in.o - Section mismatch: reference to .init.text: from .text between 'kmem_cache_create' (at offset 0x18a6b) and 'cache_reap' With this patch: MODPOST vmlinux WARNING: mm/built-in.o - Section mismatch: reference to .init.text:set_up_list3s from .text between 'kmem_cache_create' (at offset 0x18a39) and 'cache_reap' WARNING: mm/built-in.o - Section mismatch: reference to .init.text:set_up_list3s from .text between 'kmem_cache_create' (at offset 0x18a6b) and 'cache_reap' Now modpost can detect "kernel_init" name (and whitelist it) and show "set_up_list3s" name.

Atsushi Nemoto committed 19 years ago

Commit f892b7d1 parent 25601202 files · +82 −0Browse files

Showing the changes to scripts (2 of 2 files). Show all

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2 files

scripts/mod/modpost.c +79 −0
scripts/mod/modpost.h +3 −0

scripts/mod/modpost.c+79−0

@@ -384,6 +384,7 @@ static int parse_elf(struct elf_info info, const char filename) · 383 unmodified lines
384	sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size);	384	sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size);
385	sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link);	385	sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link);
386	sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name);	386	sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name);
		387	sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info);
387	}	388	}
388	/* Find symbol table. */	389	/* Find symbol table. */
389	for (i = 1; i < hdr->e_shnum; i++) {	390	for (i = 1; i < hdr->e_shnum; i++) {
@@ -773,6 +774,8 @@ static Elf_Sym find_elf_symbol(struct elf_info elf, Elf_Addr addr, · 383 unmodified lines
773	for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {	774	for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
774	if (sym->st_shndx != relsym->st_shndx)	775	if (sym->st_shndx != relsym->st_shndx)
775	continue;	776	continue;
		777	if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
		778	continue;
776	if (sym->st_value == addr)	779	if (sym->st_value == addr)
777	return sym;	780	return sym;
778	}	781	}
@@ -910,6 +913,68 @@ static void warn_sec_mismatch(const char modname, const char fromsec, · 131 unmodified lines
910	}	913	}
911	}	914	}
912		915
		916	static void addend_386_rel(struct elf_info elf, int section, Elf_Rela r)
		917	{
		918	Elf_Shdr *sechdrs = elf->sechdrs;
		919	unsigned int r_typ;
		920	unsigned int *location;
		921
		922	r_typ = ELF_R_TYPE(r->r_info);
		923	location = (void *)elf->hdr +
		924	sechdrs[sechdrs[section].sh_info].sh_offset + r->r_offset;
		925	switch (r_typ) {
		926	case R_386_32:
		927	r->r_addend = TO_NATIVE(*location);
		928	break;
		929	case R_386_PC32:
		930	r->r_addend = TO_NATIVE(*location) + 4;
		931	break;
		932	}
		933	}
		934
		935	static void addend_arm_rel(struct elf_info elf, int section, Elf_Rela r)
		936	{
		937	Elf_Shdr *sechdrs = elf->sechdrs;
		938	unsigned int r_typ;
		939	unsigned int *location;
		940
		941	r_typ = ELF_R_TYPE(r->r_info);
		942	location = (void *)elf->hdr +
		943	sechdrs[sechdrs[section].sh_info].sh_offset + r->r_offset;
		944	switch (r_typ) {
		945	case R_ARM_ABS32:
		946	r->r_addend = TO_NATIVE(*location);
		947	break;
		948	case R_ARM_PC24:
		949	r->r_addend = ((TO_NATIVE(*location) & 0x00ffffff) << 2) + 8;
		950	break;
		951	}
		952	}
		953
		954	static int addend_mips_rel(struct elf_info elf, int section, Elf_Rela r)
		955	{
		956	Elf_Shdr *sechdrs = elf->sechdrs;
		957	unsigned int r_typ;
		958	unsigned int *location;
		959	unsigned int inst;
		960
		961	r_typ = ELF_R_TYPE(r->r_info);
		962	if (r_typ == R_MIPS_HI16)
		963	return 1; /* skip this */
		964	location = (void *)elf->hdr +
		965	sechdrs[sechdrs[section].sh_info].sh_offset + r->r_offset;
		966	inst = TO_NATIVE(*location);
		967	switch (r_typ) {
		968	case R_MIPS_LO16:
		969	r->r_addend = ((inst & 0xffff) ^ 0x8000) - 0x8000;
		970	break;
		971	case R_MIPS_26:
		972	r->r_addend = (inst & 0x03ffffff) << 2;
		973	break;
		974	}
		975	return 0;
		976	}
		977
913	/**	978	/**
914	* A module includes a number of sections that are discarded	979	* A module includes a number of sections that are discarded
915	* either when loaded or when used as built-in.	980	* either when loaded or when used as built-in.
@@ -953,8 +1018,11 @@ static void check_sec_ref(struct module mod, const char modname, · 37 unmodified lines
953	r.r_offset = TO_NATIVE(rela->r_offset);	1018	r.r_offset = TO_NATIVE(rela->r_offset);
954	#if KERNEL_ELFCLASS == ELFCLASS64	1019	#if KERNEL_ELFCLASS == ELFCLASS64
955	if (hdr->e_machine == EM_MIPS) {	1020	if (hdr->e_machine == EM_MIPS) {
		1021	unsigned int r_typ;
956	r_sym = ELF64_MIPS_R_SYM(rela->r_info);	1022	r_sym = ELF64_MIPS_R_SYM(rela->r_info);
957	r_sym = TO_NATIVE(r_sym);	1023	r_sym = TO_NATIVE(r_sym);
		1024	r_typ = ELF64_MIPS_R_TYPE(rela->r_info);
		1025	r.r_info = ELF64_R_INFO(r_sym, r_typ);
958	} else {	1026	} else {
959	r.r_info = TO_NATIVE(rela->r_info);	1027	r.r_info = TO_NATIVE(rela->r_info);
960	r_sym = ELF_R_SYM(r.r_info);	1028	r_sym = ELF_R_SYM(r.r_info);
@@ -987,8 +1055,11 @@ static void check_sec_ref(struct module mod, const char modname, · 26 unmodified lines
987	r.r_offset = TO_NATIVE(rel->r_offset);	1055	r.r_offset = TO_NATIVE(rel->r_offset);
988	#if KERNEL_ELFCLASS == ELFCLASS64	1056	#if KERNEL_ELFCLASS == ELFCLASS64
989	if (hdr->e_machine == EM_MIPS) {	1057	if (hdr->e_machine == EM_MIPS) {
		1058	unsigned int r_typ;
990	r_sym = ELF64_MIPS_R_SYM(rel->r_info);	1059	r_sym = ELF64_MIPS_R_SYM(rel->r_info);
991	r_sym = TO_NATIVE(r_sym);	1060	r_sym = TO_NATIVE(r_sym);
		1061	r_typ = ELF64_MIPS_R_TYPE(rel->r_info);
		1062	r.r_info = ELF64_R_INFO(r_sym, r_typ);
992	} else {	1063	} else {
993	r.r_info = TO_NATIVE(rel->r_info);	1064	r.r_info = TO_NATIVE(rel->r_info);
994	r_sym = ELF_R_SYM(r.r_info);	1065	r_sym = ELF_R_SYM(r.r_info);
@@ -998,6 +1069,14 @@ static void check_sec_ref(struct module mod, const char modname, · 3 unmodified lines
998	r_sym = ELF_R_SYM(r.r_info);	1069	r_sym = ELF_R_SYM(r.r_info);
999	#endif	1070	#endif
1000	r.r_addend = 0;	1071	r.r_addend = 0;
		1072	if (hdr->e_machine == EM_386)
		1073	addend_386_rel(elf, i, &r);
		1074	else if (hdr->e_machine == EM_ARM)
		1075	addend_arm_rel(elf, i, &r);
		1076	else if (hdr->e_machine == EM_MIPS) {
		1077	if (addend_mips_rel(elf, i, &r))
		1078	continue;
		1079	}
1001	sym = elf->symtab_start + r_sym;	1080	sym = elf->symtab_start + r_sym;
1002	/* Skip special sections */	1081	/* Skip special sections */
1003	if (sym->st_shndx >= SHN_LORESERVE)	1082	if (sym->st_shndx >= SHN_LORESERVE)

scripts/mod/modpost.h+3−0

@@ -60,6 +60,9 @@ typedef union · 59 unmodified lines
60	#define ELF64_MIPS_R_SYM(i) \	60	#define ELF64_MIPS_R_SYM(i) \
61	((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_sym)	61	((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_sym)
62		62
		63	#define ELF64_MIPS_R_TYPE(i) \
		64	((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_type1)
		65
63	#if KERNEL_ELFDATA != HOST_ELFDATA	66	#if KERNEL_ELFDATA != HOST_ELFDATA
64		67
65	static inline void __endian(const void src, void dest, unsigned int size)	68	static inline void __endian(const void src, void dest, unsigned int size)

kbuild: make better section mismatch reports on i386, arm and mips

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