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author | Masahiro Yamada <masahiroy@kernel.org> | 2022-05-13 14:39:22 +0300 |
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committer | Masahiro Yamada <masahiroy@kernel.org> | 2022-05-24 10:33:20 +0300 |
commit | 7b4537199a4a8480b8c3ba37a2d44765ce76cd9b (patch) | |
tree | 0690afa62208ca15fd36069afcbdac85908d0676 /scripts/genksyms/genksyms.c | |
parent | f292d875d0dc700b3af0bef04c5abc1dc7b3b62c (diff) | |
download | linux-7b4537199a4a8480b8c3ba37a2d44765ce76cd9b.tar.xz |
kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS
include/{linux,asm-generic}/export.h defines a weak symbol, __crc_*
as a placeholder.
Genksyms writes the version CRCs into the linker script, which will be
used for filling the __crc_* symbols. The linker script format depends
on CONFIG_MODULE_REL_CRCS. If it is enabled, __crc_* holds the offset
to the reference of CRC.
It is time to get rid of this complexity.
Now that modpost parses text files (.*.cmd) to collect all the CRCs,
it can generate C code that will be linked to the vmlinux or modules.
Generate a new C file, .vmlinux.export.c, which contains the CRCs of
symbols exported by vmlinux. It is compiled and linked to vmlinux in
scripts/link-vmlinux.sh.
Put the CRCs of symbols exported by modules into the existing *.mod.c
files. No additional build step is needed for modules. As before,
*.mod.c are compiled and linked to *.ko in scripts/Makefile.modfinal.
No linker magic is used here. The new C implementation works in the
same way, whether CONFIG_RELOCATABLE is enabled or not.
CONFIG_MODULE_REL_CRCS is no longer needed.
Previously, Kbuild invoked additional $(LD) to update the CRCs in
objects, but this step is unneeded too.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nicolas Schier <nicolas@fjasle.eu>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
Diffstat (limited to 'scripts/genksyms/genksyms.c')
-rw-r--r-- | scripts/genksyms/genksyms.c | 18 |
1 files changed, 4 insertions, 14 deletions
diff --git a/scripts/genksyms/genksyms.c b/scripts/genksyms/genksyms.c index 4827c5abe5b7..67b23cc0df0f 100644 --- a/scripts/genksyms/genksyms.c +++ b/scripts/genksyms/genksyms.c @@ -33,7 +33,7 @@ char *cur_filename; int in_source_file; static int flag_debug, flag_dump_defs, flag_reference, flag_dump_types, - flag_preserve, flag_warnings, flag_rel_crcs; + flag_preserve, flag_warnings; static int errors; static int nsyms; @@ -680,11 +680,7 @@ void export_symbol(const char *name) if (flag_dump_defs) fputs(">\n", debugfile); - /* Used as a linker script. */ - printf(!flag_rel_crcs ? "__crc_%s = 0x%08lx;\n" : - "SECTIONS { .rodata : ALIGN(4) { " - "__crc_%s = .; LONG(0x%08lx); } }\n", - name, crc); + printf("__crc_%s = 0x%08lx;\n", name, crc); } } @@ -733,7 +729,6 @@ static void genksyms_usage(void) " -q, --quiet Disable warnings (default)\n" " -h, --help Print this message\n" " -V, --version Print the release version\n" - " -R, --relative-crc Emit section relative symbol CRCs\n" #else /* __GNU_LIBRARY__ */ " -s Select symbol prefix\n" " -d Increment the debug level (repeatable)\n" @@ -745,7 +740,6 @@ static void genksyms_usage(void) " -q Disable warnings (default)\n" " -h Print this message\n" " -V Print the release version\n" - " -R Emit section relative symbol CRCs\n" #endif /* __GNU_LIBRARY__ */ , stderr); } @@ -766,14 +760,13 @@ int main(int argc, char **argv) {"preserve", 0, 0, 'p'}, {"version", 0, 0, 'V'}, {"help", 0, 0, 'h'}, - {"relative-crc", 0, 0, 'R'}, {0, 0, 0, 0} }; - while ((o = getopt_long(argc, argv, "s:dwqVDr:T:phR", + while ((o = getopt_long(argc, argv, "s:dwqVDr:T:ph", &long_opts[0], NULL)) != EOF) #else /* __GNU_LIBRARY__ */ - while ((o = getopt(argc, argv, "s:dwqVDr:T:phR")) != EOF) + while ((o = getopt(argc, argv, "s:dwqVDr:T:ph")) != EOF) #endif /* __GNU_LIBRARY__ */ switch (o) { case 'd': @@ -813,9 +806,6 @@ int main(int argc, char **argv) case 'h': genksyms_usage(); return 0; - case 'R': - flag_rel_crcs = 1; - break; default: genksyms_usage(); return 1; |