Buildresult: kbuild/x86_64-defconfig/x86_64-gcc8 built on Jun 15 2023, 06:19

kisskb

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Status:	OK
Date/Time:	Jun 15 2023, 06:19
Duration:	0:02:34.250705
Builder:	alpine1
Revision:	kbuild: generate KSYMTAB entries by modpost (`172cf4686df073be968f87939f485e076c8f2791)`
Target:	kbuild/x86_64-defconfig/x86_64-gcc8
Branch:	kbuild
Compiler:	x86_64-gcc8 (x86_64-linux-gcc (GCC) 8.5.0 / GNU ld (GNU Binutils) 2.36.1)
Config:	defconfig (download)
Log:	Download original No warnings found in log. Full Log # git rev-parse -q --verify 172cf4686df073be968f87939f485e076c8f2791^{commit} 172cf4686df073be968f87939f485e076c8f2791 already have revision, skipping fetch # git checkout -q -f -B kisskb 172cf4686df073be968f87939f485e076c8f2791 # git clean -qxdf # < git log -1 # commit 172cf4686df073be968f87939f485e076c8f2791 # Author: Masahiro Yamada <masahiroy@kernel.org> # Date: Mon Jun 12 00:50:52 2023 +0900 # # kbuild: generate KSYMTAB entries by modpost # # Commit 7b4537199a4a ("kbuild: link symbol CRCs at final link, removing # CONFIG_MODULE_REL_CRCS") made modpost output CRCs in the same way # whether the EXPORT_SYMBOL() is placed in .c or .S. # # For further cleanups, this commit applies a similar approach to the # entire data structure of EXPORT_SYMBOL(). # # The EXPORT_SYMBOL() compilation is split into two stages. # # When a source file is compiled, EXPORT_SYMBOL() is converted into a # dummy symbol in the .export_symbol section. # # For example, # # EXPORT_SYMBOL(foo); # EXPORT_SYMBOL_NS_GPL(bar, BAR_NAMESPACE); # # will be encoded into the following assembly code: # # .section ".export_symbol","a" # __export_symbol_foo: # .asciz "" # .asciz "" # .balign 8 # .quad foo # .previous # # .section ".export_symbol","a" # __export_symbol_bar: # .asciz "GPL" # .asciz "BAR_NAMESPACE" # .balign 8 # .quad bar # .previous # # They are mere markers to tell modpost the name, license, and namespace # of the symbols. They will be dropped from the final vmlinux and modules # because the (.export_symbol) will go into /DISCARD/ in the linker script. # # Then, modpost extracts all the information about EXPORT_SYMBOL() from the # .export_symbol section, and generates the final C code: # # KSYMTAB_FUNC(foo, "", ""); # KSYMTAB_FUNC(bar, "_gpl", "BAR_NAMESPACE"); # # KSYMTAB_FUNC() (or KSYMTAB_DATA() if it is data) is expanded to struct # kernel_symbol that will be linked to the vmlinux or a module. # # With this change, EXPORT_SYMBOL() works in the same way for .c and .S # files, providing the following benefits. # # [1] Deprecate EXPORT_DATA_SYMBOL() # # In the old days, EXPORT_SYMBOL() was only available in C files. To export # a symbol in .S, EXPORT_SYMBOL() was placed in a separate .c file. # arch/arm/kernel/armksyms.c is one example written in the classic manner. # # Commit 22823ab419d8 ("EXPORT_SYMBOL() for asm") removed this limitation. # Since then, EXPORT_SYMBOL() can be placed close to the symbol definition # in .S files. It was a nice improvement. # # However, as that commit mentioned, you need to use EXPORT_DATA_SYMBOL() # for data objects on some architectures. # # In the new approach, modpost checks symbol's type (STT_FUNC or not), # and outputs KSYMTAB_FUNC() or KSYMTAB_DATA() accordingly. # # There are only two users of EXPORT_DATA_SYMBOL: # # EXPORT_DATA_SYMBOL_GPL(empty_zero_page) (arch/ia64/kernel/head.S) # EXPORT_DATA_SYMBOL(ia64_ivt) (arch/ia64/kernel/ivt.S) # # They are transformed as follows and output into .vmlinux.export.c # # KSYMTAB_DATA(empty_zero_page, "_gpl", ""); # KSYMTAB_DATA(ia64_ivt, "", ""); # # The other EXPORT_SYMBOL users in ia64 assembly are output as # KSYMTAB_FUNC(). # # EXPORT_DATA_SYMBOL() is now deprecated. # # [2] merge <linux/export.h> and <asm-generic/export.h> # # There are two similar header implementations: # # include/linux/export.h for .c files # include/asm-generic/export.h for .S files # # Ideally, the functionality should be consistent between them, but they # tend to diverge. # # Commit 8651ec01daed ("module: add support for symbol namespaces.") did # not support the namespace for .S files. # # This commit shifts the essential implementation part to C, which supports # EXPORT_SYMBOL_NS() for .S files. # # <asm/export.h> and <asm-generic/export.h> will remain as a wrapper of # <linux/export.h> for a while. # # They will be removed after #include <asm/export.h> directives are all # replaced with #include <linux/export.h>. # # [3] Implement CONFIG_TRIM_UNUSED_KSYMS in one-pass algorithm (by a later commit) # # When CONFIG_TRIM_UNUSED_KSYMS is enabled, Kbuild recursively traverses # the directory tree to determine which EXPORT_SYMBOL to trim. If an # EXPORT_SYMBOL turns out to be unused by anyone, Kbuild begins the # second traverse, where some source files are recompiled with their # EXPORT_SYMBOL() tuned into a no-op. # # We can do this better now; modpost can selectively emit KSYMTAB entries # that are really used by modules. # # Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> # Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> # < /opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux-ld --version # < git log --format=%s --max-count=1 172cf4686df073be968f87939f485e076c8f2791 # make -s -j 160 ARCH=x86 O=/kisskb/build/kbuild_x86_64_defconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux- x86_64_defconfig # < make -s -j 160 ARCH=x86 O=/kisskb/build/kbuild_x86_64_defconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux- help # make -s -j 160 ARCH=x86 O=/kisskb/build/kbuild_x86_64_defconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux- olddefconfig # make -s -j 160 ARCH=x86 O=/kisskb/build/kbuild_x86_64_defconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux- Completed OK # rm -rf /kisskb/build/kbuild_x86_64_defconfig_x86_64-gcc8 # Build took: 0:02:34.250705

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