user/sven/linux.git/scripts/Makefile.build, branch v5.13.16

Kbuild: lto: fix module versionings mismatch in GNU make 3.X

2021-07-28T12:37:26Z

[ Upstream commit 1d11053dc63094075bf9e4809fffd3bb5e72f9a6 ] When building modules(CONFIG_...=m), I found some of module versions are incorrect and set to 0. This can be found in build log for first clean build which shows WARNING: EXPORT symbol "XXXX" [drivers/XXX/XXX.ko] version generation failed, symbol will not be versioned. But in second build(incremental build), the WARNING disappeared and the module version becomes valid CRC and make someone who want to change modules without updating kernel image can't insert their modules. The problematic code is + $(foreach n, $(filter-out FORCE,$^), \ + $(if $(wildcard $(n).symversions), \ + ; cat $(n).symversions >> $@.symversions)) For example: rm -f fs/notify/built-in.a.symversions ; rm -f fs/notify/built-in.a; \ llvm-ar cDPrST fs/notify/built-in.a fs/notify/fsnotify.o \ fs/notify/notification.o fs/notify/group.o ... `foreach n` shows nothing to `cat` into $(n).symversions because `if $(wildcard $(n).symversions)` return nothing, but actually they do exist during this line was executed. -rw-r--r-- 1 root root 168580 Jun 13 19:10 fs/notify/fsnotify.o -rw-r--r-- 1 root root 111 Jun 13 19:10 fs/notify/fsnotify.o.symversions The reason is the $(n).symversions are generated at runtime, but Makefile wildcard function expends and checks the file exist or not during parsing the Makefile. Thus fix this by use `test` shell command to check the file existence in runtime. Rebase from both: 1. [https://lore.kernel.org/lkml/20210616080252.32046-1-lecopzer.chen@mediatek.com/] 2. [https://lore.kernel.org/lkml/20210702032943.7865-1-lecopzer.chen@mediatek.com/] Fixes: 38e891849003 ("kbuild: lto: fix module versioning") Co-developed-by: Sami Tolvanen Signed-off-by: Lecopzer Chen Signed-off-by: Masahiro Yamada Signed-off-by: Sasha Levin

kbuild: Fix objtool dependency for 'OBJECT_FILES_NON_STANDARD_ := n'

2021-07-14T15:06:40Z

[ Upstream commit 8852c552402979508fdc395ae07aa8761aa46045 ] "OBJECT_FILES_NON_STANDARD_vma.o := n" has a dependency bug. When objtool source is updated, the affected object doesn't get re-analyzed by objtool. Peter's new variable-sized jump label feature relies on objtool rewriting the object file. Otherwise the system can fail to boot. That effectively upgrades this minor dependency issue to a major bug. The problem is that variables in prerequisites are expanded early, during the read-in phase. The '$(objtool_dep)' variable indirectly uses '$@', which isn't yet available when the target prerequisites are evaluated. Use '.SECONDEXPANSION:' which causes '$(objtool_dep)' to be expanded in a later phase, after the target-specific '$@' variable has been defined. Fixes: b9ab5ebb14ec ("objtool: Add CONFIG_STACK_VALIDATION option") Fixes: ab3257042c26 ("jump_label, x86: Allow short NOPs") Reported-by: Matthew Wilcox Signed-off-by: Josh Poimboeuf Signed-off-by: Sasha Levin

kbuild: refactor fdtoverlay rule

2021-05-05T17:14:38Z

Rename overlay-y to multi-dtb-y, which is a consistent name with multi-obj-y. Also, use multi-search to avoid code duplication. Introduce real-dtb-y, which is a consistent name with real-obj-y, to contain primitive blobs compiled from *.dts. This is used to calculate the list of *.dt.yaml files. Set -@ to base DTB without using $(eval ). Signed-off-by: Masahiro Yamada

kbuild: redo fake deps at include/config/*.h

2021-04-24T20:26:10Z

Make include/config/foo/bar.h fake deps files generation simpler. * delete .h suffix those aren't header files, shorten filenames, * delete tolower() Linux filesystems can deal with both upper and lowercase filenames very well, * put everything in 1 directory Presumably 'mkdir -p' split is from dark times when filesystems handled huge directories badly, disks were round adding to seek times. x86_64 allmodconfig lists 12364 files in include/config. ../obj/include/config/ ├── 104_QUAD_8 ├── 60XX_WDT ├── 64BIT ... ├── ZSWAP_DEFAULT_ON ├── ZSWAP_ZPOOL_DEFAULT └── ZSWAP_ZPOOL_DEFAULT_ZBUD 0 directories, 12364 files Signed-off-by: Alexey Dobriyan Signed-off-by: Masahiro Yamada

kbuild: rename multi-used-* to multi-obj-*

2021-04-24T20:12:34Z

I think multi-obj-* is clearer, and more consistent with real-obj-*. Rename as follows: multi-used-y -> multi-obj-y multi-used-m -> multi-obj-m multi-used -> multi-obj-ym Signed-off-by: Masahiro Yamada

kbuild: split cc-option and friends to scripts/Makefile.compiler

2021-04-24T20:09:32Z

scripts/Kbuild.include is included everywhere, but macros such as cc-option are needed by build targets only. For example, when 'make clean' traverses the tree, it does not need to evaluate $(call cc-option,). Split cc-option, ld-option, etc. to scripts/Makefile.compiler, which is only included from the top Makefile and scripts/Makefile.build. Signed-off-by: Masahiro Yamada

kbuild: prefix $(srctree)/ to some included Makefiles

2021-03-15T10:20:48Z

VPATH is used in Kbuild to make pattern rules search for prerequisites in both $(objtree) and $(srctree). Some of *.c, *.S files are not real sources, but generated by tools such as flex, bison, perl. In contrast, I doubt the benefit of --include-dir=$(abs_srctree) because it is always clear which Makefiles are real sources, and which are not. So, my hope is to add $(srctree)/ prefix to all check-in Makefiles, then remove --include-dir=$(abs_srctree) flag in the future. I am touching only some Kbuild core parts for now. Treewide fixes will be needed to achieve this goal. Signed-off-by: Masahiro Yamada

Merge tag 'kbuild-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2021-02-25T18:17:31Z

Pull Kbuild updates from Masahiro Yamada: - Fix false-positive build warnings for ARCH=ia64 builds - Optimize dictionary size for module compression with xz - Check the compiler and linker versions in Kconfig - Fix misuse of extra-y - Support DWARF v5 debug info - Clamp SUBLEVEL to 255 because stable releases 4.4.x and 4.9.x exceeded the limit - Add generic syscall{tbl,hdr}.sh for cleanups across arches - Minor cleanups of genksyms - Minor cleanups of Kconfig * tag 'kbuild-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (38 commits) initramfs: Remove redundant dependency of RD_ZSTD on BLK_DEV_INITRD kbuild: remove deprecated 'always' and 'hostprogs-y/m' kbuild: parse C= and M= before changing the working directory kbuild: reuse this-makefile to define abs_srctree kconfig: unify rule of config, menuconfig, nconfig, gconfig, xconfig kconfig: omit --oldaskconfig option for 'make config' kconfig: fix 'invalid option' for help option kconfig: remove dead code in conf_askvalue() kconfig: clean up nested if-conditionals in check_conf() kconfig: Remove duplicate call to sym_get_string_value() Makefile: Remove # characters from compiler string Makefile: reuse CC_VERSION_TEXT kbuild: check the minimum linker version in Kconfig kbuild: remove ld-version macro scripts: add generic syscallhdr.sh scripts: add generic syscalltbl.sh arch: syscalls: remove $(srctree)/ prefix from syscall tables arch: syscalls: add missing FORCE and fix 'targets' to make if_changed work gen_compile_commands: prune some directories kbuild: simplify access to the kernel's version ...

kbuild: remove deprecated 'always' and 'hostprogs-y/m'

2021-02-24T06:12:06Z

These have no more user in the upstream code. The use of them has been warned for a while for external modules. The migration is finished. Signed-off-by: Masahiro Yamada

kbuild: lto: postpone objtool

2021-02-23T20:46:57Z

With LTO, LLVM bitcode won't be compiled into native code until modpost_link, or modfinal for modules. This change postpones calls to objtool until after these steps, and moves objtool_args to Makefile.lib, so the arguments can be reused in Makefile.modfinal. As we didn't have objects to process earlier, we use --duplicate when processing vmlinux.o. This change also disables unreachable instruction warnings with LTO to avoid warnings about the int3 padding between functions. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook