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Revert "kbuild: strip generated symbols from *.ko"

This reverts commit ad7a953.

And commit: ("allow stripping of generated symbols under CONFIG_KALLSYMS_ALL")
            9bb4824

These stripping patches has caused a set of issues:

1) People have reported compatibility issues with binutils due to
   lack of support for `--strip-unneeded-symbols' with objcopy 2.15.92.0.2
   Reported by: Wenji
2) ccache and distcc no longer works as expeced
   Reported by: Ted, Roland, + others
3) The installed modules increased a lot in size
   Reported by: Ted, Davej + others

Reported-by: Wenji Huang <wenji.huang@oracle.com>
Reported-by: "Theodore Ts'o" <tytso@mit.edu>
Reported-by: Dave Jones <davej@redhat.com>
Reported-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
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1 parent a652504 commit 2ea038917bbdd51a7ae4a898c6a04641324dd033 Sam Ravnborg committed Jan 14, 2009
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@@ -606,25 +606,20 @@ export INSTALL_PATH ?= /boot
MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
export MODLIB
-strip-symbols := $(srctree)/scripts/strip-symbols \
- $(wildcard $(srctree)/arch/$(ARCH)/scripts/strip-symbols)
-
#
-# INSTALL_MOD_STRIP, if defined, will cause modules to be stripped while
-# they get installed. If INSTALL_MOD_STRIP is '1', then the default
-# options (see below) will be used. Otherwise, INSTALL_MOD_STRIP will
-# be used as the option(s) to the objcopy command.
+# INSTALL_MOD_STRIP, if defined, will cause modules to be
+# stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
+# the default option --strip-debug will be used. Otherwise,
+# INSTALL_MOD_STRIP will used as the options to the strip command.
+
ifdef INSTALL_MOD_STRIP
ifeq ($(INSTALL_MOD_STRIP),1)
-mod_strip_cmd = $(OBJCOPY) --strip-debug
-ifeq ($(CONFIG_KALLSYMS_ALL),$(CONFIG_KALLSYMS_STRIP_GENERATED))
-mod_strip_cmd += --wildcard $(addprefix --strip-symbols ,$(strip-symbols))
-endif
+mod_strip_cmd = $(STRIP) --strip-debug
else
-mod_strip_cmd = $(OBJCOPY) $(INSTALL_MOD_STRIP)
+mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
endif # INSTALL_MOD_STRIP=1
else
-mod_strip_cmd = false
+mod_strip_cmd = true
endif # INSTALL_MOD_STRIP
export mod_strip_cmd
@@ -754,7 +749,6 @@ last_kallsyms := 2
endif
kallsyms.o := .tmp_kallsyms$(last_kallsyms).o
-kallsyms.h := $(wildcard include/config/kallsyms/*.h) $(wildcard include/config/kallsyms/*/*.h)
define verify_kallsyms
$(Q)$(if $($(quiet)cmd_sysmap), \
@@ -779,41 +773,24 @@ endef
# Generate .S file with all kernel symbols
quiet_cmd_kallsyms = KSYM $@
- cmd_kallsyms = { test $* -eq 0 || $(NM) -n $<; } \
- | $(KALLSYMS) $(if $(CONFIG_KALLSYMS_ALL),--all-symbols) >$@
-
-quiet_cmd_kstrip = STRIP $@
- cmd_kstrip = $(OBJCOPY) --wildcard $(addprefix --strip$(if $(CONFIG_RELOCATABLE),-unneeded)-symbols ,$(filter %/scripts/strip-symbols,$^)) $< $@
+ cmd_kallsyms = $(NM) -n $< | $(KALLSYMS) \
+ $(if $(CONFIG_KALLSYMS_ALL),--all-symbols) > $@
-$(foreach n,0 1 2 3,.tmp_kallsyms$(n).o): KBUILD_AFLAGS += -Wa,--strip-local-absolute
-$(foreach n,0 1 2 3,.tmp_kallsyms$(n).o): %.o: %.S scripts FORCE
+.tmp_kallsyms1.o .tmp_kallsyms2.o .tmp_kallsyms3.o: %.o: %.S scripts FORCE
$(call if_changed_dep,as_o_S)
-ifeq ($(CONFIG_KALLSYMS_STRIP_GENERATED),y)
-strip-ext := .stripped
-endif
-
-.tmp_kallsyms%.S: .tmp_vmlinux%$(strip-ext) $(KALLSYMS) $(kallsyms.h)
+.tmp_kallsyms%.S: .tmp_vmlinux% $(KALLSYMS)
$(call cmd,kallsyms)
-# make -jN seems to have problems with intermediate files, see bug #3330.
-.SECONDARY: $(foreach n,1 2 3,.tmp_vmlinux$(n).stripped)
-.tmp_vmlinux%.stripped: .tmp_vmlinux% $(strip-symbols) $(kallsyms.h)
- $(call cmd,kstrip)
-
-ifneq ($(CONFIG_DEBUG_INFO),y)
-.tmp_vmlinux%: LDFLAGS_vmlinux += -S
-endif
# .tmp_vmlinux1 must be complete except kallsyms, so update vmlinux version
-.tmp_vmlinux%: $(vmlinux-lds) $(vmlinux-all) FORCE
- $(if $(filter 1,$*),$(call if_changed_rule,ksym_ld),$(call if_changed,vmlinux__))
+.tmp_vmlinux1: $(vmlinux-lds) $(vmlinux-all) FORCE
+ $(call if_changed_rule,ksym_ld)
-.tmp_vmlinux0$(strip-ext):
- $(Q)echo "placeholder" >$@
+.tmp_vmlinux2: $(vmlinux-lds) $(vmlinux-all) .tmp_kallsyms1.o FORCE
+ $(call if_changed,vmlinux__)
-.tmp_vmlinux1: .tmp_kallsyms0.o
-.tmp_vmlinux2: .tmp_kallsyms1.o
-.tmp_vmlinux3: .tmp_kallsyms2.o
+.tmp_vmlinux3: $(vmlinux-lds) $(vmlinux-all) .tmp_kallsyms2.o FORCE
+ $(call if_changed,vmlinux__)
# Needs to visit scripts/ before $(KALLSYMS) can be used.
$(KALLSYMS): scripts ;
@@ -1 +0,0 @@
-__cpu_vendor_dev_X86_VENDOR_*
View
@@ -626,13 +626,6 @@ config KALLSYMS_ALL
Say N.
-config KALLSYMS_STRIP_GENERATED
- bool "Strip machine generated symbols from kallsyms"
- depends on KALLSYMS_ALL
- default y
- help
- Say N if you want kallsyms to retain even machine generated symbols.
-
config KALLSYMS_EXTRA_PASS
bool "Do an extra kallsyms pass"
depends on KALLSYMS
View
@@ -30,19 +30,20 @@
#define all_var 0
#endif
-extern const unsigned long kallsyms_addresses[];
-extern const u8 kallsyms_names[];
+/* These will be re-linked against their real values during the second link stage */
+extern const unsigned long kallsyms_addresses[] __attribute__((weak));
+extern const u8 kallsyms_names[] __attribute__((weak));
/* tell the compiler that the count isn't in the small data section if the arch
* has one (eg: FRV)
*/
extern const unsigned long kallsyms_num_syms
- __attribute__((__section__(".rodata")));
+__attribute__((weak, section(".rodata")));
-extern const u8 kallsyms_token_table[];
-extern const u16 kallsyms_token_index[];
+extern const u8 kallsyms_token_table[] __attribute__((weak));
+extern const u16 kallsyms_token_index[] __attribute__((weak));
-extern const unsigned long kallsyms_markers[];
+extern const unsigned long kallsyms_markers[] __attribute__((weak));
static inline int is_kernel_inittext(unsigned long addr)
{
@@ -167,6 +168,9 @@ static unsigned long get_symbol_pos(unsigned long addr,
unsigned long symbol_start = 0, symbol_end = 0;
unsigned long i, low, high, mid;
+ /* This kernel should never had been booted. */
+ BUG_ON(!kallsyms_addresses);
+
/* do a binary search on the sorted kallsyms_addresses array */
low = 0;
high = kallsyms_num_syms;
View
@@ -151,16 +151,16 @@ cmd_cc_i_c = $(CPP) $(c_flags) -o $@ $<
$(obj)/%.i: $(src)/%.c FORCE
$(call if_changed_dep,cc_i_c)
-cmd_genksyms = \
+cmd_gensymtypes = \
$(CPP) -D__GENKSYMS__ $(c_flags) $< | \
- $(GENKSYMS) -T $@ -A -a $(ARCH) \
+ $(GENKSYMS) -T $@ -a $(ARCH) \
$(if $(KBUILD_PRESERVE),-p) \
$(if $(1),-r $(firstword $(wildcard $(@:.symtypes=.symref) /dev/null)))
quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@
cmd_cc_symtypes_c = \
set -e; \
- $(call cmd_genksyms, true) >/dev/null; \
+ $(call cmd_gensymtypes, true) >/dev/null; \
test -s $@ || rm -f $@
$(obj)/%.symtypes : $(src)/%.c FORCE
@@ -177,38 +177,28 @@ cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
else
# When module versioning is enabled the following steps are executed:
-# o compile a .tmp_<file>.s from <file>.c
-# o if .tmp_<file>.s doesn't contain a __ksymtab version, i.e. does
-# not export symbols, we just assemble .tmp_<file>.s to <file>.o and
+# o compile a .tmp_<file>.o from <file>.c
+# o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does
+# not export symbols, we just rename .tmp_<file>.o to <file>.o and
# are done.
# o otherwise, we calculate symbol versions using the good old
# genksyms on the preprocessed source and postprocess them in a way
-# that they are usable as assembly source
-# o assemble <file>.o from .tmp_<file>.s forcing inclusion of directives
-# defining the actual values of __crc_*, followed by objcopy-ing them
-# to force these symbols to be local to permit stripping them later.
-s_file = $(@D)/.tmp_$(@F:.o=.s)
-v_file = $(@D)/.tmp_$(@F:.o=.v)
-tmp_o_file = $(@D)/.tmp_$(@F)
-no_g_c_flags = $(filter-out -g%,$(c_flags))
-
-cmd_cc_o_c = $(CC) $(c_flags) -S -o $(s_file) $<
+# that they are usable as a linker script
+# o generate <file>.o from .tmp_<file>.o using the linker to
+# replace the unresolved symbols __crc_exported_symbol with
+# the actual value of the checksum generated by genksyms
+cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<
cmd_modversions = \
- if grep -q __ksymtab $(s_file); then \
- if $(call cmd_genksyms, $(KBUILD_SYMTYPES)) > $(v_file) \
- && $(CC) $(no_g_c_flags) -c -Wa,$(v_file) \
- -o $(tmp_o_file) $(s_file) \
- && $(OBJCOPY) -L '__crc_*' -L '___crc_*' -w \
- $(tmp_o_file) $@; \
- then \
- : ; \
- else \
- rm -f $@; exit 1; \
- fi; \
+ if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then \
+ $(call cmd_gensymtypes, $(KBUILD_SYMTYPES)) \
+ > $(@D)/.tmp_$(@F:.o=.ver); \
+ \
+ $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F) \
+ -T $(@D)/.tmp_$(@F:.o=.ver); \
+ rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver); \
else \
- rm -f $(v_file); \
- $(CC) $(no_g_c_flags) -c -o $@ $(s_file); \
+ mv -f $(@D)/.tmp_$(@F) $@; \
fi;
endif
@@ -225,12 +215,7 @@ define rule_cc_o_c
$(cmd_record_mcount) \
scripts/basic/fixdep $(depfile) $@ '$(call make-cmd,cc_o_c)' > \
$(dot-target).tmp; \
- if [ -r $(@D)/.tmp_$(@F:.o=.v) ]; then \
- echo >> $(dot-target).tmp; \
- echo '$@: $(GENKSYMS)' >> $(dot-target).tmp; \
- echo '$(GENKSYMS):: ;' >> $(dot-target).tmp; \
- fi; \
- rm -f $(depfile) $(@D)/.tmp_$(@F:.o=.?); \
+ rm -f $(depfile); \
mv -f $(dot-target).tmp $(dot-target).cmd
endef
View
@@ -17,8 +17,7 @@ __modinst: $(modules)
@:
quiet_cmd_modules_install = INSTALL $@
- cmd_modules_install = mkdir -p $(2); \
- $(mod_strip_cmd) $@ $(2)/$(notdir $@) || cp $@ $(2)
+ cmd_modules_install = mkdir -p $(2); cp $@ $(2) ; $(mod_strip_cmd) $(2)/$(notdir $@)
# Modules built outside the kernel source tree go into extra by default
INSTALL_MOD_DIR ?= extra
@@ -43,7 +43,7 @@ int cur_line = 1;
char *cur_filename;
static int flag_debug, flag_dump_defs, flag_reference, flag_dump_types,
- flag_preserve, flag_warnings, flag_asm;
+ flag_preserve, flag_warnings;
static const char *arch = "";
static const char *mod_prefix = "";
@@ -610,11 +610,8 @@ void export_symbol(const char *name)
if (flag_dump_defs)
fputs(">\n", debugfile);
- /* Used as assembly source or a linker script. */
- printf(flag_asm
- ? ".equiv %s__crc_%s, %#08lx\n"
- : "%s__crc_%s = %#08lx ;\n",
- mod_prefix, name, crc);
+ /* Used as a linker script. */
+ printf("%s__crc_%s = 0x%08lx ;\n", mod_prefix, name, crc);
}
}
@@ -651,10 +648,9 @@ void error_with_pos(const char *fmt, ...)
static void genksyms_usage(void)
{
- fputs("Usage:\n" "genksyms [-aAdDTwqhV] > /path/to/.tmp_obj.ver\n" "\n"
+ fputs("Usage:\n" "genksyms [-adDTwqhV] > /path/to/.tmp_obj.ver\n" "\n"
#ifdef __GNU_LIBRARY__
" -a, --arch Select architecture\n"
- " -A, --asm Generate assembly rather than linker script\n"
" -d, --debug Increment the debug level (repeatable)\n"
" -D, --dump Dump expanded symbol defs (for debugging only)\n"
" -r, --reference file Read reference symbols from a file\n"
@@ -666,7 +662,6 @@ static void genksyms_usage(void)
" -V, --version Print the release version\n"
#else /* __GNU_LIBRARY__ */
" -a Select architecture\n"
- " -A Generate assembly rather than linker script\n"
" -d Increment the debug level (repeatable)\n"
" -D Dump expanded symbol defs (for debugging only)\n"
" -r file Read reference symbols from a file\n"
@@ -688,7 +683,6 @@ int main(int argc, char **argv)
#ifdef __GNU_LIBRARY__
struct option long_opts[] = {
{"arch", 1, 0, 'a'},
- {"asm", 0, 0, 'A'},
{"debug", 0, 0, 'd'},
{"warnings", 0, 0, 'w'},
{"quiet", 0, 0, 'q'},
@@ -701,10 +695,10 @@ int main(int argc, char **argv)
{0, 0, 0, 0}
};
- while ((o = getopt_long(argc, argv, "a:dwqVADr:T:ph",
+ while ((o = getopt_long(argc, argv, "a:dwqVDr:T:ph",
&long_opts[0], NULL)) != EOF)
#else /* __GNU_LIBRARY__ */
- while ((o = getopt(argc, argv, "a:dwqVADr:T:ph")) != EOF)
+ while ((o = getopt(argc, argv, "a:dwqVDr:T:ph")) != EOF)
#endif /* __GNU_LIBRARY__ */
switch (o) {
case 'a':
@@ -722,9 +716,6 @@ int main(int argc, char **argv)
case 'V':
fputs("genksyms version 2.5.60\n", stderr);
break;
- case 'A':
- flag_asm = 1;
- break;
case 'D':
flag_dump_defs = 1;
break;
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