* [PATCH 0/2] Buildtime exception table sorting for relative entries. @ 2012-04-24 18:23 David Daney 2012-04-24 18:23 ` [PATCH 1/2] scripts/sortextable: Handle relative entries, and other cleanups David Daney 2012-04-24 18:23 ` [PATCH 2/2] Revert "x86, extable: Disable presorted exception table for now" David Daney 0 siblings, 2 replies; 5+ messages in thread From: David Daney @ 2012-04-24 18:23 UTC (permalink / raw) To: Ralf Baechle, Thomas Gleixner, Ingo Molnar, H. Peter Anvin, x86, Linus Torvalds, Michal Marek Cc: linux-kernel, linux-mips, Andrew Morton, David Daney From: David Daney <ddaney@caviumnetworks.com> These are against HPA's x86/extable branch in the tip repo. Light testing indicates that it works for x86_64, and MIPS64. x86_32 looks good, but I didn't try to boot the resulting kernel. But really, what could go wrong with something so simple? David Daney (2): scripts/sortextable: Handle relative entries, and other cleanups. Revert "x86, extable: Disable presorted exception table for now" arch/x86/Kconfig | 1 + scripts/Makefile | 2 + scripts/sortextable.c | 171 ++++++++++++++++++++++++++++++++----------------- scripts/sortextable.h | 79 +++++++++++++++-------- 4 files changed, 165 insertions(+), 88 deletions(-) -- 1.7.7.6 ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH 1/2] scripts/sortextable: Handle relative entries, and other cleanups. 2012-04-24 18:23 [PATCH 0/2] Buildtime exception table sorting for relative entries David Daney @ 2012-04-24 18:23 ` David Daney 2012-04-24 21:18 ` [tip:x86/extable] " tip-bot for David Daney 2012-04-24 18:23 ` [PATCH 2/2] Revert "x86, extable: Disable presorted exception table for now" David Daney 1 sibling, 1 reply; 5+ messages in thread From: David Daney @ 2012-04-24 18:23 UTC (permalink / raw) To: Ralf Baechle, Thomas Gleixner, Ingo Molnar, H. Peter Anvin, x86, Linus Torvalds, Michal Marek Cc: linux-kernel, linux-mips, Andrew Morton, David Daney From: David Daney <david.daney@cavium.com> x86 is now using relative rather than absolute addresses in its exception table, so we add a sorter for these. If there are relocations on the __ex_table section, they are redundant after the sort, so they are zeroed out leaving them valid and consistent. Also use the unaligned safe accessors from tools/{be,le}_byteshift.h Signed-off-by: David Daney <david.daney@cavium.com> --- scripts/Makefile | 2 + scripts/sortextable.c | 171 ++++++++++++++++++++++++++++++++----------------- scripts/sortextable.h | 79 +++++++++++++++-------- 3 files changed, 164 insertions(+), 88 deletions(-) diff --git a/scripts/Makefile b/scripts/Makefile index 43e19b9..9eace52 100644 --- a/scripts/Makefile +++ b/scripts/Makefile @@ -15,6 +15,8 @@ hostprogs-$(CONFIG_IKCONFIG) += bin2c hostprogs-$(BUILD_C_RECORDMCOUNT) += recordmcount hostprogs-$(CONFIG_BUILDTIME_EXTABLE_SORT) += sortextable +HOSTCFLAGS_sortextable.o = -I$(srctree)/tools/include + always := $(hostprogs-y) $(hostprogs-m) # The following hostprogs-y programs are only build on demand diff --git a/scripts/sortextable.c b/scripts/sortextable.c index f51f1d4..1ca9ceb 100644 --- a/scripts/sortextable.c +++ b/scripts/sortextable.c @@ -1,7 +1,7 @@ /* * sortextable.c: Sort the kernel's exception table * - * Copyright 2011 Cavium, Inc. + * Copyright 2011 - 2012 Cavium, Inc. * * Based on code taken from recortmcount.c which is: * @@ -28,6 +28,9 @@ #include <string.h> #include <unistd.h> +#include <tools/be_byteshift.h> +#include <tools/le_byteshift.h> + static int fd_map; /* File descriptor for file being modified. */ static int mmap_failed; /* Boolean flag. */ static void *ehdr_curr; /* current ElfXX_Ehdr * for resource cleanup */ @@ -94,109 +97,157 @@ static void *mmap_file(char const *fname) return addr; } -/* w8rev, w8nat, ...: Handle endianness. */ - -static uint64_t w8rev(uint64_t const x) +static uint64_t r8be(const uint64_t *x) { - return ((0xff & (x >> (0 * 8))) << (7 * 8)) - | ((0xff & (x >> (1 * 8))) << (6 * 8)) - | ((0xff & (x >> (2 * 8))) << (5 * 8)) - | ((0xff & (x >> (3 * 8))) << (4 * 8)) - | ((0xff & (x >> (4 * 8))) << (3 * 8)) - | ((0xff & (x >> (5 * 8))) << (2 * 8)) - | ((0xff & (x >> (6 * 8))) << (1 * 8)) - | ((0xff & (x >> (7 * 8))) << (0 * 8)); + return get_unaligned_be64(x); } - -static uint32_t w4rev(uint32_t const x) +static uint32_t rbe(const uint32_t *x) { - return ((0xff & (x >> (0 * 8))) << (3 * 8)) - | ((0xff & (x >> (1 * 8))) << (2 * 8)) - | ((0xff & (x >> (2 * 8))) << (1 * 8)) - | ((0xff & (x >> (3 * 8))) << (0 * 8)); + return get_unaligned_be32(x); } - -static uint32_t w2rev(uint16_t const x) +static uint16_t r2be(const uint16_t *x) { - return ((0xff & (x >> (0 * 8))) << (1 * 8)) - | ((0xff & (x >> (1 * 8))) << (0 * 8)); + return get_unaligned_be16(x); } - -static uint64_t w8nat(uint64_t const x) +static uint64_t r8le(const uint64_t *x) { - return x; + return get_unaligned_le64(x); } - -static uint32_t w4nat(uint32_t const x) +static uint32_t rle(const uint32_t *x) +{ + return get_unaligned_le32(x); +} +static uint16_t r2le(const uint16_t *x) { - return x; + return get_unaligned_le16(x); } -static uint32_t w2nat(uint16_t const x) +static void w8be(uint64_t val, uint64_t *x) +{ + put_unaligned_be64(val, x); +} +static void wbe(uint32_t val, uint32_t *x) +{ + put_unaligned_be32(val, x); +} +static void w2be(uint16_t val, uint16_t *x) +{ + put_unaligned_be16(val, x); +} +static void w8le(uint64_t val, uint64_t *x) +{ + put_unaligned_le64(val, x); +} +static void wle(uint32_t val, uint32_t *x) +{ + put_unaligned_le32(val, x); +} +static void w2le(uint16_t val, uint16_t *x) { - return x; + put_unaligned_le16(val, x); } -static uint64_t (*w8)(uint64_t); -static uint32_t (*w)(uint32_t); -static uint32_t (*w2)(uint16_t); +static uint64_t (*r8)(const uint64_t *); +static uint32_t (*r)(const uint32_t *); +static uint16_t (*r2)(const uint16_t *); +static void (*w8)(uint64_t, uint64_t *); +static void (*w)(uint32_t, uint32_t *); +static void (*w2)(uint16_t, uint16_t *); +typedef void (*table_sort_t)(char *, int); /* 32 bit and 64 bit are very similar */ #include "sortextable.h" #define SORTEXTABLE_64 #include "sortextable.h" +static int compare_x86_table(const void *a, const void *b) +{ + int32_t av = (int32_t)r(a); + int32_t bv = (int32_t)r(b); + + if (av < bv) + return -1; + if (av > bv) + return 1; + return 0; +} + +static void sort_x86_table(char *extab_image, int image_size) +{ + int i; + + /* + * Do the same thing the runtime sort does, first normalize to + * being relative to the start of the section. + */ + i = 0; + while (i < image_size) { + uint32_t *loc = (uint32_t *)(extab_image + i); + w(r(loc) + i, loc); + i += 4; + } + + qsort(extab_image, image_size / 8, 8, compare_x86_table); + + /* Now denormalize. */ + i = 0; + while (i < image_size) { + uint32_t *loc = (uint32_t *)(extab_image + i); + w(r(loc) - i, loc); + i += 4; + } +} static void do_file(char const *const fname) { - Elf32_Ehdr *const ehdr = mmap_file(fname); + table_sort_t custom_sort; + Elf32_Ehdr *ehdr = mmap_file(fname); ehdr_curr = ehdr; - w = w4nat; - w2 = w2nat; - w8 = w8nat; switch (ehdr->e_ident[EI_DATA]) { - static unsigned int const endian = 1; default: fprintf(stderr, "unrecognized ELF data encoding %d: %s\n", ehdr->e_ident[EI_DATA], fname); fail_file(); break; case ELFDATA2LSB: - if (*(unsigned char const *)&endian != 1) { - /* main() is big endian, file.o is little endian. */ - w = w4rev; - w2 = w2rev; - w8 = w8rev; - } + r = rle; + r2 = r2le; + r8 = r8le; + w = wle; + w2 = w2le; + w8 = w8le; break; case ELFDATA2MSB: - if (*(unsigned char const *)&endian != 0) { - /* main() is little endian, file.o is big endian. */ - w = w4rev; - w2 = w2rev; - w8 = w8rev; - } + r = rbe; + r2 = r2be; + r8 = r8be; + w = wbe; + w2 = w2be; + w8 = w8be; break; } /* end switch */ if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0 - || w2(ehdr->e_type) != ET_EXEC + || r2(&ehdr->e_type) != ET_EXEC || ehdr->e_ident[EI_VERSION] != EV_CURRENT) { fprintf(stderr, "unrecognized ET_EXEC file %s\n", fname); fail_file(); } - switch (w2(ehdr->e_machine)) { + custom_sort = NULL; + switch (r2(&ehdr->e_machine)) { default: fprintf(stderr, "unrecognized e_machine %d %s\n", - w2(ehdr->e_machine), fname); + r2(&ehdr->e_machine), fname); fail_file(); break; case EM_386: - case EM_MIPS: case EM_X86_64: + custom_sort = sort_x86_table; + break; + case EM_MIPS: break; } /* end switch */ @@ -207,23 +258,23 @@ do_file(char const *const fname) fail_file(); break; case ELFCLASS32: - if (w2(ehdr->e_ehsize) != sizeof(Elf32_Ehdr) - || w2(ehdr->e_shentsize) != sizeof(Elf32_Shdr)) { + if (r2(&ehdr->e_ehsize) != sizeof(Elf32_Ehdr) + || r2(&ehdr->e_shentsize) != sizeof(Elf32_Shdr)) { fprintf(stderr, "unrecognized ET_EXEC file: %s\n", fname); fail_file(); } - do32(ehdr, fname); + do32(ehdr, fname, custom_sort); break; case ELFCLASS64: { Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr; - if (w2(ghdr->e_ehsize) != sizeof(Elf64_Ehdr) - || w2(ghdr->e_shentsize) != sizeof(Elf64_Shdr)) { + if (r2(&ghdr->e_ehsize) != sizeof(Elf64_Ehdr) + || r2(&ghdr->e_shentsize) != sizeof(Elf64_Shdr)) { fprintf(stderr, "unrecognized ET_EXEC file: %s\n", fname); fail_file(); } - do64(ghdr, fname); + do64(ghdr, fname, custom_sort); break; } } /* end switch */ diff --git a/scripts/sortextable.h b/scripts/sortextable.h index bb6aaf1..e4fd45b 100644 --- a/scripts/sortextable.h +++ b/scripts/sortextable.h @@ -1,7 +1,7 @@ /* * sortextable.h * - * Copyright 2011 Cavium, Inc. + * Copyright 2011 - 2012 Cavium, Inc. * * Some of this code was taken out of recordmcount.h written by: * @@ -30,6 +30,7 @@ #undef fn_ELF_R_SYM #undef fn_ELF_R_INFO #undef uint_t +#undef _r #undef _w #ifdef SORTEXTABLE_64 @@ -51,6 +52,7 @@ # define fn_ELF_R_SYM fn_ELF64_R_SYM # define fn_ELF_R_INFO fn_ELF64_R_INFO # define uint_t uint64_t +# define _r r8 # define _w w8 #else # define extable_ent_size 8 @@ -71,23 +73,24 @@ # define fn_ELF_R_SYM fn_ELF32_R_SYM # define fn_ELF_R_INFO fn_ELF32_R_INFO # define uint_t uint32_t +# define _r r # define _w w #endif static int compare_extable(const void *a, const void *b) { - const uint_t *aa = a; - const uint_t *bb = b; + Elf_Addr av = _r(a); + Elf_Addr bv = _r(b); - if (_w(*aa) < _w(*bb)) + if (av < bv) return -1; - if (_w(*aa) > _w(*bb)) + if (av > bv) return 1; return 0; } static void -do_func(Elf_Ehdr *const ehdr, char const *const fname) +do_func(Elf_Ehdr *ehdr, char const *const fname, table_sort_t custom_sort) { Elf_Shdr *shdr; Elf_Shdr *shstrtab_sec; @@ -97,19 +100,31 @@ do_func(Elf_Ehdr *const ehdr, char const *const fname) Elf_Sym *sym; Elf_Sym *sort_needed_sym; Elf_Shdr *sort_needed_sec; + Elf_Rel *relocs = NULL; + int relocs_size; uint32_t *sort_done_location; const char *secstrtab; const char *strtab; + char *extab_image; + int extab_index = 0; int i; int idx; - shdr = (Elf_Shdr *)((void *)ehdr + _w(ehdr->e_shoff)); - shstrtab_sec = shdr + w2(ehdr->e_shstrndx); - secstrtab = (const char *)ehdr + _w(shstrtab_sec->sh_offset); - for (i = 0; i < w2(ehdr->e_shnum); i++) { - idx = w(shdr[i].sh_name); - if (strcmp(secstrtab + idx, "__ex_table") == 0) + shdr = (Elf_Shdr *)((char *)ehdr + _r(&ehdr->e_shoff)); + shstrtab_sec = shdr + r2(&ehdr->e_shstrndx); + secstrtab = (const char *)ehdr + _r(&shstrtab_sec->sh_offset); + for (i = 0; i < r2(&ehdr->e_shnum); i++) { + idx = r(&shdr[i].sh_name); + if (strcmp(secstrtab + idx, "__ex_table") == 0) { extab_sec = shdr + i; + extab_index = i; + } + if ((r(&shdr[i].sh_type) == SHT_REL || + r(&shdr[i].sh_type) == SHT_RELA) && + r(&shdr[i].sh_info) == extab_index) { + relocs = (void *)ehdr + _r(&shdr[i].sh_offset); + relocs_size = _r(&shdr[i].sh_size); + } if (strcmp(secstrtab + idx, ".symtab") == 0) symtab_sec = shdr + i; if (strcmp(secstrtab + idx, ".strtab") == 0) @@ -127,21 +142,29 @@ do_func(Elf_Ehdr *const ehdr, char const *const fname) fprintf(stderr, "no __ex_table in file: %s\n", fname); fail_file(); } - strtab = (const char *)ehdr + _w(strtab_sec->sh_offset); + strtab = (const char *)ehdr + _r(&strtab_sec->sh_offset); - /* Sort the table in place */ - qsort((void *)ehdr + _w(extab_sec->sh_offset), - (_w(extab_sec->sh_size) / extable_ent_size), - extable_ent_size, compare_extable); + extab_image = (void *)ehdr + _r(&extab_sec->sh_offset); + + if (custom_sort) { + custom_sort(extab_image, _r(&extab_sec->sh_size)); + } else { + int num_entries = _r(&extab_sec->sh_size) / extable_ent_size; + qsort(extab_image, num_entries, + extable_ent_size, compare_extable); + } + /* If there were relocations, we no longer need them. */ + if (relocs) + memset(relocs, 0, relocs_size); /* find main_extable_sort_needed */ sort_needed_sym = NULL; - for (i = 0; i < _w(symtab_sec->sh_size) / sizeof(Elf_Sym); i++) { - sym = (void *)ehdr + _w(symtab_sec->sh_offset); + for (i = 0; i < _r(&symtab_sec->sh_size) / sizeof(Elf_Sym); i++) { + sym = (void *)ehdr + _r(&symtab_sec->sh_offset); sym += i; if (ELF_ST_TYPE(sym->st_info) != STT_OBJECT) continue; - idx = w(sym->st_name); + idx = r(&sym->st_name); if (strcmp(strtab + idx, "main_extable_sort_needed") == 0) { sort_needed_sym = sym; break; @@ -153,16 +176,16 @@ do_func(Elf_Ehdr *const ehdr, char const *const fname) fname); fail_file(); } - sort_needed_sec = &shdr[w2(sort_needed_sym->st_shndx)]; + sort_needed_sec = &shdr[r2(&sort_needed_sym->st_shndx)]; sort_done_location = (void *)ehdr + - _w(sort_needed_sec->sh_offset) + - _w(sort_needed_sym->st_value) - - _w(sort_needed_sec->sh_addr); + _r(&sort_needed_sec->sh_offset) + + _r(&sort_needed_sym->st_value) - + _r(&sort_needed_sec->sh_addr); +#if 1 printf("sort done marker at %lx\n", - (unsigned long) (_w(sort_needed_sec->sh_offset) + - _w(sort_needed_sym->st_value) - - _w(sort_needed_sec->sh_addr))); + (unsigned long)((char *)sort_done_location - (char *)ehdr)); +#endif /* We sorted it, clear the flag. */ - *sort_done_location = 0; + w(0, sort_done_location); } -- 1.7.7.6 ^ permalink raw reply [flat|nested] 5+ messages in thread
* [tip:x86/extable] scripts/sortextable: Handle relative entries, and other cleanups 2012-04-24 18:23 ` [PATCH 1/2] scripts/sortextable: Handle relative entries, and other cleanups David Daney @ 2012-04-24 21:18 ` tip-bot for David Daney 0 siblings, 0 replies; 5+ messages in thread From: tip-bot for David Daney @ 2012-04-24 21:18 UTC (permalink / raw) To: linux-tip-commits; +Cc: linux-kernel, hpa, mingo, david.daney, tglx Commit-ID: d59a16836d917548cf41eda3369936684d527f5f Gitweb: http://git.kernel.org/tip/d59a16836d917548cf41eda3369936684d527f5f Author: David Daney <david.daney@cavium.com> AuthorDate: Tue, 24 Apr 2012 11:23:14 -0700 Committer: H. Peter Anvin <hpa@zytor.com> CommitDate: Tue, 24 Apr 2012 11:42:20 -0700 scripts/sortextable: Handle relative entries, and other cleanups x86 is now using relative rather than absolute addresses in its exception table, so we add a sorter for these. If there are relocations on the __ex_table section, they are redundant and probably incorrect after the sort, so they are zeroed out leaving them valid and consistent. Also use the unaligned safe accessors from tools/{be,le}_byteshift.h Signed-off-by: David Daney <david.daney@cavium.com> Link: http://lkml.kernel.org/r/1335291795-26693-2-git-send-email-ddaney.cavm@gmail.com Signed-off-by: H. Peter Anvin <hpa@zytor.com> --- scripts/Makefile | 2 + scripts/sortextable.c | 171 ++++++++++++++++++++++++++++++++----------------- scripts/sortextable.h | 79 +++++++++++++++-------- 3 files changed, 164 insertions(+), 88 deletions(-) diff --git a/scripts/Makefile b/scripts/Makefile index 43e19b9..9eace52 100644 --- a/scripts/Makefile +++ b/scripts/Makefile @@ -15,6 +15,8 @@ hostprogs-$(CONFIG_IKCONFIG) += bin2c hostprogs-$(BUILD_C_RECORDMCOUNT) += recordmcount hostprogs-$(CONFIG_BUILDTIME_EXTABLE_SORT) += sortextable +HOSTCFLAGS_sortextable.o = -I$(srctree)/tools/include + always := $(hostprogs-y) $(hostprogs-m) # The following hostprogs-y programs are only build on demand diff --git a/scripts/sortextable.c b/scripts/sortextable.c index f51f1d4..1ca9ceb 100644 --- a/scripts/sortextable.c +++ b/scripts/sortextable.c @@ -1,7 +1,7 @@ /* * sortextable.c: Sort the kernel's exception table * - * Copyright 2011 Cavium, Inc. + * Copyright 2011 - 2012 Cavium, Inc. * * Based on code taken from recortmcount.c which is: * @@ -28,6 +28,9 @@ #include <string.h> #include <unistd.h> +#include <tools/be_byteshift.h> +#include <tools/le_byteshift.h> + static int fd_map; /* File descriptor for file being modified. */ static int mmap_failed; /* Boolean flag. */ static void *ehdr_curr; /* current ElfXX_Ehdr * for resource cleanup */ @@ -94,109 +97,157 @@ static void *mmap_file(char const *fname) return addr; } -/* w8rev, w8nat, ...: Handle endianness. */ - -static uint64_t w8rev(uint64_t const x) +static uint64_t r8be(const uint64_t *x) { - return ((0xff & (x >> (0 * 8))) << (7 * 8)) - | ((0xff & (x >> (1 * 8))) << (6 * 8)) - | ((0xff & (x >> (2 * 8))) << (5 * 8)) - | ((0xff & (x >> (3 * 8))) << (4 * 8)) - | ((0xff & (x >> (4 * 8))) << (3 * 8)) - | ((0xff & (x >> (5 * 8))) << (2 * 8)) - | ((0xff & (x >> (6 * 8))) << (1 * 8)) - | ((0xff & (x >> (7 * 8))) << (0 * 8)); + return get_unaligned_be64(x); } - -static uint32_t w4rev(uint32_t const x) +static uint32_t rbe(const uint32_t *x) { - return ((0xff & (x >> (0 * 8))) << (3 * 8)) - | ((0xff & (x >> (1 * 8))) << (2 * 8)) - | ((0xff & (x >> (2 * 8))) << (1 * 8)) - | ((0xff & (x >> (3 * 8))) << (0 * 8)); + return get_unaligned_be32(x); } - -static uint32_t w2rev(uint16_t const x) +static uint16_t r2be(const uint16_t *x) { - return ((0xff & (x >> (0 * 8))) << (1 * 8)) - | ((0xff & (x >> (1 * 8))) << (0 * 8)); + return get_unaligned_be16(x); } - -static uint64_t w8nat(uint64_t const x) +static uint64_t r8le(const uint64_t *x) { - return x; + return get_unaligned_le64(x); } - -static uint32_t w4nat(uint32_t const x) +static uint32_t rle(const uint32_t *x) +{ + return get_unaligned_le32(x); +} +static uint16_t r2le(const uint16_t *x) { - return x; + return get_unaligned_le16(x); } -static uint32_t w2nat(uint16_t const x) +static void w8be(uint64_t val, uint64_t *x) +{ + put_unaligned_be64(val, x); +} +static void wbe(uint32_t val, uint32_t *x) +{ + put_unaligned_be32(val, x); +} +static void w2be(uint16_t val, uint16_t *x) +{ + put_unaligned_be16(val, x); +} +static void w8le(uint64_t val, uint64_t *x) +{ + put_unaligned_le64(val, x); +} +static void wle(uint32_t val, uint32_t *x) +{ + put_unaligned_le32(val, x); +} +static void w2le(uint16_t val, uint16_t *x) { - return x; + put_unaligned_le16(val, x); } -static uint64_t (*w8)(uint64_t); -static uint32_t (*w)(uint32_t); -static uint32_t (*w2)(uint16_t); +static uint64_t (*r8)(const uint64_t *); +static uint32_t (*r)(const uint32_t *); +static uint16_t (*r2)(const uint16_t *); +static void (*w8)(uint64_t, uint64_t *); +static void (*w)(uint32_t, uint32_t *); +static void (*w2)(uint16_t, uint16_t *); +typedef void (*table_sort_t)(char *, int); /* 32 bit and 64 bit are very similar */ #include "sortextable.h" #define SORTEXTABLE_64 #include "sortextable.h" +static int compare_x86_table(const void *a, const void *b) +{ + int32_t av = (int32_t)r(a); + int32_t bv = (int32_t)r(b); + + if (av < bv) + return -1; + if (av > bv) + return 1; + return 0; +} + +static void sort_x86_table(char *extab_image, int image_size) +{ + int i; + + /* + * Do the same thing the runtime sort does, first normalize to + * being relative to the start of the section. + */ + i = 0; + while (i < image_size) { + uint32_t *loc = (uint32_t *)(extab_image + i); + w(r(loc) + i, loc); + i += 4; + } + + qsort(extab_image, image_size / 8, 8, compare_x86_table); + + /* Now denormalize. */ + i = 0; + while (i < image_size) { + uint32_t *loc = (uint32_t *)(extab_image + i); + w(r(loc) - i, loc); + i += 4; + } +} static void do_file(char const *const fname) { - Elf32_Ehdr *const ehdr = mmap_file(fname); + table_sort_t custom_sort; + Elf32_Ehdr *ehdr = mmap_file(fname); ehdr_curr = ehdr; - w = w4nat; - w2 = w2nat; - w8 = w8nat; switch (ehdr->e_ident[EI_DATA]) { - static unsigned int const endian = 1; default: fprintf(stderr, "unrecognized ELF data encoding %d: %s\n", ehdr->e_ident[EI_DATA], fname); fail_file(); break; case ELFDATA2LSB: - if (*(unsigned char const *)&endian != 1) { - /* main() is big endian, file.o is little endian. */ - w = w4rev; - w2 = w2rev; - w8 = w8rev; - } + r = rle; + r2 = r2le; + r8 = r8le; + w = wle; + w2 = w2le; + w8 = w8le; break; case ELFDATA2MSB: - if (*(unsigned char const *)&endian != 0) { - /* main() is little endian, file.o is big endian. */ - w = w4rev; - w2 = w2rev; - w8 = w8rev; - } + r = rbe; + r2 = r2be; + r8 = r8be; + w = wbe; + w2 = w2be; + w8 = w8be; break; } /* end switch */ if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0 - || w2(ehdr->e_type) != ET_EXEC + || r2(&ehdr->e_type) != ET_EXEC || ehdr->e_ident[EI_VERSION] != EV_CURRENT) { fprintf(stderr, "unrecognized ET_EXEC file %s\n", fname); fail_file(); } - switch (w2(ehdr->e_machine)) { + custom_sort = NULL; + switch (r2(&ehdr->e_machine)) { default: fprintf(stderr, "unrecognized e_machine %d %s\n", - w2(ehdr->e_machine), fname); + r2(&ehdr->e_machine), fname); fail_file(); break; case EM_386: - case EM_MIPS: case EM_X86_64: + custom_sort = sort_x86_table; + break; + case EM_MIPS: break; } /* end switch */ @@ -207,23 +258,23 @@ do_file(char const *const fname) fail_file(); break; case ELFCLASS32: - if (w2(ehdr->e_ehsize) != sizeof(Elf32_Ehdr) - || w2(ehdr->e_shentsize) != sizeof(Elf32_Shdr)) { + if (r2(&ehdr->e_ehsize) != sizeof(Elf32_Ehdr) + || r2(&ehdr->e_shentsize) != sizeof(Elf32_Shdr)) { fprintf(stderr, "unrecognized ET_EXEC file: %s\n", fname); fail_file(); } - do32(ehdr, fname); + do32(ehdr, fname, custom_sort); break; case ELFCLASS64: { Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr; - if (w2(ghdr->e_ehsize) != sizeof(Elf64_Ehdr) - || w2(ghdr->e_shentsize) != sizeof(Elf64_Shdr)) { + if (r2(&ghdr->e_ehsize) != sizeof(Elf64_Ehdr) + || r2(&ghdr->e_shentsize) != sizeof(Elf64_Shdr)) { fprintf(stderr, "unrecognized ET_EXEC file: %s\n", fname); fail_file(); } - do64(ghdr, fname); + do64(ghdr, fname, custom_sort); break; } } /* end switch */ diff --git a/scripts/sortextable.h b/scripts/sortextable.h index bb6aaf1..e4fd45b 100644 --- a/scripts/sortextable.h +++ b/scripts/sortextable.h @@ -1,7 +1,7 @@ /* * sortextable.h * - * Copyright 2011 Cavium, Inc. + * Copyright 2011 - 2012 Cavium, Inc. * * Some of this code was taken out of recordmcount.h written by: * @@ -30,6 +30,7 @@ #undef fn_ELF_R_SYM #undef fn_ELF_R_INFO #undef uint_t +#undef _r #undef _w #ifdef SORTEXTABLE_64 @@ -51,6 +52,7 @@ # define fn_ELF_R_SYM fn_ELF64_R_SYM # define fn_ELF_R_INFO fn_ELF64_R_INFO # define uint_t uint64_t +# define _r r8 # define _w w8 #else # define extable_ent_size 8 @@ -71,23 +73,24 @@ # define fn_ELF_R_SYM fn_ELF32_R_SYM # define fn_ELF_R_INFO fn_ELF32_R_INFO # define uint_t uint32_t +# define _r r # define _w w #endif static int compare_extable(const void *a, const void *b) { - const uint_t *aa = a; - const uint_t *bb = b; + Elf_Addr av = _r(a); + Elf_Addr bv = _r(b); - if (_w(*aa) < _w(*bb)) + if (av < bv) return -1; - if (_w(*aa) > _w(*bb)) + if (av > bv) return 1; return 0; } static void -do_func(Elf_Ehdr *const ehdr, char const *const fname) +do_func(Elf_Ehdr *ehdr, char const *const fname, table_sort_t custom_sort) { Elf_Shdr *shdr; Elf_Shdr *shstrtab_sec; @@ -97,19 +100,31 @@ do_func(Elf_Ehdr *const ehdr, char const *const fname) Elf_Sym *sym; Elf_Sym *sort_needed_sym; Elf_Shdr *sort_needed_sec; + Elf_Rel *relocs = NULL; + int relocs_size; uint32_t *sort_done_location; const char *secstrtab; const char *strtab; + char *extab_image; + int extab_index = 0; int i; int idx; - shdr = (Elf_Shdr *)((void *)ehdr + _w(ehdr->e_shoff)); - shstrtab_sec = shdr + w2(ehdr->e_shstrndx); - secstrtab = (const char *)ehdr + _w(shstrtab_sec->sh_offset); - for (i = 0; i < w2(ehdr->e_shnum); i++) { - idx = w(shdr[i].sh_name); - if (strcmp(secstrtab + idx, "__ex_table") == 0) + shdr = (Elf_Shdr *)((char *)ehdr + _r(&ehdr->e_shoff)); + shstrtab_sec = shdr + r2(&ehdr->e_shstrndx); + secstrtab = (const char *)ehdr + _r(&shstrtab_sec->sh_offset); + for (i = 0; i < r2(&ehdr->e_shnum); i++) { + idx = r(&shdr[i].sh_name); + if (strcmp(secstrtab + idx, "__ex_table") == 0) { extab_sec = shdr + i; + extab_index = i; + } + if ((r(&shdr[i].sh_type) == SHT_REL || + r(&shdr[i].sh_type) == SHT_RELA) && + r(&shdr[i].sh_info) == extab_index) { + relocs = (void *)ehdr + _r(&shdr[i].sh_offset); + relocs_size = _r(&shdr[i].sh_size); + } if (strcmp(secstrtab + idx, ".symtab") == 0) symtab_sec = shdr + i; if (strcmp(secstrtab + idx, ".strtab") == 0) @@ -127,21 +142,29 @@ do_func(Elf_Ehdr *const ehdr, char const *const fname) fprintf(stderr, "no __ex_table in file: %s\n", fname); fail_file(); } - strtab = (const char *)ehdr + _w(strtab_sec->sh_offset); + strtab = (const char *)ehdr + _r(&strtab_sec->sh_offset); - /* Sort the table in place */ - qsort((void *)ehdr + _w(extab_sec->sh_offset), - (_w(extab_sec->sh_size) / extable_ent_size), - extable_ent_size, compare_extable); + extab_image = (void *)ehdr + _r(&extab_sec->sh_offset); + + if (custom_sort) { + custom_sort(extab_image, _r(&extab_sec->sh_size)); + } else { + int num_entries = _r(&extab_sec->sh_size) / extable_ent_size; + qsort(extab_image, num_entries, + extable_ent_size, compare_extable); + } + /* If there were relocations, we no longer need them. */ + if (relocs) + memset(relocs, 0, relocs_size); /* find main_extable_sort_needed */ sort_needed_sym = NULL; - for (i = 0; i < _w(symtab_sec->sh_size) / sizeof(Elf_Sym); i++) { - sym = (void *)ehdr + _w(symtab_sec->sh_offset); + for (i = 0; i < _r(&symtab_sec->sh_size) / sizeof(Elf_Sym); i++) { + sym = (void *)ehdr + _r(&symtab_sec->sh_offset); sym += i; if (ELF_ST_TYPE(sym->st_info) != STT_OBJECT) continue; - idx = w(sym->st_name); + idx = r(&sym->st_name); if (strcmp(strtab + idx, "main_extable_sort_needed") == 0) { sort_needed_sym = sym; break; @@ -153,16 +176,16 @@ do_func(Elf_Ehdr *const ehdr, char const *const fname) fname); fail_file(); } - sort_needed_sec = &shdr[w2(sort_needed_sym->st_shndx)]; + sort_needed_sec = &shdr[r2(&sort_needed_sym->st_shndx)]; sort_done_location = (void *)ehdr + - _w(sort_needed_sec->sh_offset) + - _w(sort_needed_sym->st_value) - - _w(sort_needed_sec->sh_addr); + _r(&sort_needed_sec->sh_offset) + + _r(&sort_needed_sym->st_value) - + _r(&sort_needed_sec->sh_addr); +#if 1 printf("sort done marker at %lx\n", - (unsigned long) (_w(sort_needed_sec->sh_offset) + - _w(sort_needed_sym->st_value) - - _w(sort_needed_sec->sh_addr))); + (unsigned long)((char *)sort_done_location - (char *)ehdr)); +#endif /* We sorted it, clear the flag. */ - *sort_done_location = 0; + w(0, sort_done_location); } ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH 2/2] Revert "x86, extable: Disable presorted exception table for now" 2012-04-24 18:23 [PATCH 0/2] Buildtime exception table sorting for relative entries David Daney 2012-04-24 18:23 ` [PATCH 1/2] scripts/sortextable: Handle relative entries, and other cleanups David Daney @ 2012-04-24 18:23 ` David Daney 2012-04-24 21:19 ` [tip:x86/extable] " tip-bot for David Daney 1 sibling, 1 reply; 5+ messages in thread From: David Daney @ 2012-04-24 18:23 UTC (permalink / raw) To: Ralf Baechle, Thomas Gleixner, Ingo Molnar, H. Peter Anvin, x86, Linus Torvalds, Michal Marek Cc: linux-kernel, linux-mips, Andrew Morton, David Daney From: David Daney <ddaney@caviumnetworks.com> sortextable now works with relative entries, re-enable it. Signed-off-by: David Daney <ddaney@caviumnetworks.com> --- arch/x86/Kconfig | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 1d14cc6..2f925cc 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -82,6 +82,7 @@ config X86 select ARCH_HAVE_NMI_SAFE_CMPXCHG select GENERIC_IOMAP select DCACHE_WORD_ACCESS if !DEBUG_PAGEALLOC + select BUILDTIME_EXTABLE_SORT config INSTRUCTION_DECODER def_bool (KPROBES || PERF_EVENTS) -- 1.7.7.6 ^ permalink raw reply [flat|nested] 5+ messages in thread
* [tip:x86/extable] Revert "x86, extable: Disable presorted exception table for now" 2012-04-24 18:23 ` [PATCH 2/2] Revert "x86, extable: Disable presorted exception table for now" David Daney @ 2012-04-24 21:19 ` tip-bot for David Daney 0 siblings, 0 replies; 5+ messages in thread From: tip-bot for David Daney @ 2012-04-24 21:19 UTC (permalink / raw) To: linux-tip-commits; +Cc: linux-kernel, hpa, mingo, ddaney, tglx Commit-ID: 8b5ad472991796b2347464922c72de2ca5a028f3 Gitweb: http://git.kernel.org/tip/8b5ad472991796b2347464922c72de2ca5a028f3 Author: David Daney <ddaney@caviumnetworks.com> AuthorDate: Tue, 24 Apr 2012 11:23:15 -0700 Committer: H. Peter Anvin <hpa@zytor.com> CommitDate: Tue, 24 Apr 2012 11:42:25 -0700 Revert "x86, extable: Disable presorted exception table for now" sortextable now works with relative entries, re-enable it. Signed-off-by: David Daney <ddaney@caviumnetworks.com> Link: http://lkml.kernel.org/r/1335291795-26693-3-git-send-email-ddaney.cavm@gmail.com Signed-off-by: H. Peter Anvin <hpa@zytor.com> --- arch/x86/Kconfig | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 1d14cc6..2f925cc 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -82,6 +82,7 @@ config X86 select ARCH_HAVE_NMI_SAFE_CMPXCHG select GENERIC_IOMAP select DCACHE_WORD_ACCESS if !DEBUG_PAGEALLOC + select BUILDTIME_EXTABLE_SORT config INSTRUCTION_DECODER def_bool (KPROBES || PERF_EVENTS) ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2012-04-24 21:20 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2012-04-24 18:23 [PATCH 0/2] Buildtime exception table sorting for relative entries David Daney 2012-04-24 18:23 ` [PATCH 1/2] scripts/sortextable: Handle relative entries, and other cleanups David Daney 2012-04-24 21:18 ` [tip:x86/extable] " tip-bot for David Daney 2012-04-24 18:23 ` [PATCH 2/2] Revert "x86, extable: Disable presorted exception table for now" David Daney 2012-04-24 21:19 ` [tip:x86/extable] " tip-bot for David Daney
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