From 21532b9e5bd597631cfe38d9eb34df069938065b Mon Sep 17 00:00:00 2001 From: "Tautschnig, Michael" Date: Mon, 4 Jul 2016 13:55:04 +0000 Subject: scripts: Fix size mismatch of kexec_purgatory_size bin2c is used to create a valid C file out of a binary file where two symbols will be globally defined: and _size. is passed as the first parameter of the host binary. Building using goto-cc reported that the purgatory binary code (the only current user of this utility) declares kexec_purgatory_size as 'size_t' where bin2c generate _size to be 'int' so in a 64-bit host where sizeof(size_t) > sizeof(int) this type mismatch will always yield the wrong value for big-endian architectures while for little-endian it will be wrong if the object laid in memory directly after kexec_purgatory_size contains non-zero value at the time of reading. This commit changes _size to be size_t instead. Note: Another way to fix the problem is to change the type of kexec_purgatory_size to be 'int' as there's this check in code: (kexec_purgatory_size <= 0) Signed-off-by: Michael Tautschnig Cc: Vivek Goyal Acked-by: Dave Young Signed-off-by: Michal Marek --- scripts/basic/bin2c.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'scripts/basic') diff --git a/scripts/basic/bin2c.c b/scripts/basic/bin2c.c index af187e695345..c3d7eef3ad06 100644 --- a/scripts/basic/bin2c.c +++ b/scripts/basic/bin2c.c @@ -29,7 +29,8 @@ int main(int argc, char *argv[]) } while (ch != EOF); if (argc > 1) - printf("\t;\n\nconst int %s_size = %d;\n", argv[1], total); + printf("\t;\n\n#include \n\nconst size_t %s_size = %d;\n", + argv[1], total); return 0; } -- cgit v1.2.3 From dee81e9886748594babac67c14b0f720148e255d Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Wed, 24 Aug 2016 21:03:05 +0300 Subject: fixdep: faster CONFIG_ search Do you think kernel build is 100% dominated by gcc? You are wrong! One small utility called "fixdep" consistently manages to sneak into profile's first page (unless you have small monitor of course). The choke point is this clever code: for (; m < end; m++) { if (*m == INT_CONF) { p = (char *) m ; goto conf; } if (*m == INT_ONFI) { p = (char *) m-1; goto conf; } if (*m == INT_NFIG) { p = (char *) m-2; goto conf; } if (*m == INT_FIG_) { p = (char *) m-3; goto conf; } 4 branches per 4 characters is not fast. Use strstr(3), so that SSE2 etc can be used. With this patch, fixdep is so deep at the bottom, it is hard to find it. Signed-off-by: Alexey Dobriyan Signed-off-by: Michal Marek --- scripts/basic/fixdep.c | 86 ++++++++++++++++---------------------------------- 1 file changed, 28 insertions(+), 58 deletions(-) (limited to 'scripts/basic') diff --git a/scripts/basic/fixdep.c b/scripts/basic/fixdep.c index 746ec1ece614..fff818b92acb 100644 --- a/scripts/basic/fixdep.c +++ b/scripts/basic/fixdep.c @@ -82,8 +82,7 @@ * to date before even starting the recursive build, so it's too late * at this point anyway. * - * The algorithm to grep for "CONFIG_..." is bit unusual, but should - * be fast ;-) We don't even try to really parse the header files, but + * We don't even try to really parse the header files, but * merely grep, i.e. if CONFIG_FOO is mentioned in a comment, it will * be picked up as well. It's not a problem with respect to * correctness, since that can only give too many dependencies, thus @@ -115,11 +114,6 @@ #include #include -#define INT_CONF ntohl(0x434f4e46) -#define INT_ONFI ntohl(0x4f4e4649) -#define INT_NFIG ntohl(0x4e464947) -#define INT_FIG_ ntohl(0x4649475f) - int insert_extra_deps; char *target; char *depfile; @@ -241,37 +235,22 @@ static void use_config(const char *m, int slen) print_config(m, slen); } -static void parse_config_file(const char *map, size_t len) +static void parse_config_file(const char *p) { - const int *end = (const int *) (map + len); - /* start at +1, so that p can never be < map */ - const int *m = (const int *) map + 1; - const char *p, *q; - - for (; m < end; m++) { - if (*m == INT_CONF) { p = (char *) m ; goto conf; } - if (*m == INT_ONFI) { p = (char *) m-1; goto conf; } - if (*m == INT_NFIG) { p = (char *) m-2; goto conf; } - if (*m == INT_FIG_) { p = (char *) m-3; goto conf; } - continue; - conf: - if (p > map + len - 7) - continue; - if (memcmp(p, "CONFIG_", 7)) - continue; + const char *q, *r; + + while ((p = strstr(p, "CONFIG_"))) { p += 7; - for (q = p; q < map + len; q++) { - if (!(isalnum(*q) || *q == '_')) - goto found; - } - continue; - - found: - if (!memcmp(q - 7, "_MODULE", 7)) - q -= 7; - if (q - p < 0) - continue; - use_config(p, q - p); + q = p; + while (*q && (isalnum(*q) || *q == '_')) + q++; + if (memcmp(q - 7, "_MODULE", 7) == 0) + r = q - 7; + else + r = q; + if (r > p) + use_config(p, r - p); + p = q; } } @@ -291,7 +270,7 @@ static void do_config_file(const char *filename) { struct stat st; int fd; - void *map; + char *map; fd = open(filename, O_RDONLY); if (fd < 0) { @@ -308,18 +287,23 @@ static void do_config_file(const char *filename) close(fd); return; } - map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0); - if ((long) map == -1) { - perror("fixdep: mmap"); + map = malloc(st.st_size + 1); + if (!map) { + perror("fixdep: malloc"); close(fd); return; } + if (read(fd, map, st.st_size) != st.st_size) { + perror("fixdep: read"); + close(fd); + return; + } + map[st.st_size] = '\0'; + close(fd); - parse_config_file(map, st.st_size); - - munmap(map, st.st_size); + parse_config_file(map); - close(fd); + free(map); } /* @@ -446,22 +430,8 @@ static void print_deps(void) close(fd); } -static void traps(void) -{ - static char test[] __attribute__((aligned(sizeof(int)))) = "CONF"; - int *p = (int *)test; - - if (*p != INT_CONF) { - fprintf(stderr, "fixdep: sizeof(int) != 4 or wrong endianness? %#x\n", - *p); - exit(2); - } -} - int main(int argc, char *argv[]) { - traps(); - if (argc == 5 && !strcmp(argv[1], "-e")) { insert_extra_deps = 1; argv++; -- cgit v1.2.3