kernel/linux.git/scripts/adjust_autoksyms.sh, branch v6.1.168

kbuild: split the second line of .mod into .usyms

2022-05-07T18:16:59+00:00

The *.mod files have two lines; the first line lists the member objects of the module, and the second line, if CONFIG_TRIM_UNUSED_KSYMS=y, lists the undefined symbols. Currently, we generate *.mod after constructing composite modules, otherwise, we cannot compute the second line. No prerequisite is required to print the first line. They are orthogonal. Splitting them into separate commands will ease further cleanups. This commit splits the list of undefined symbols out to *.usyms files. Previously, the list of undefined symbols ended up with a very long line, but now it has one symbol per line. Use sed like we did before commit 7d32358be8ac ("kbuild: avoid split lines in .mod files"). Signed-off-by: Masahiro Yamada Reviewed-by: Nicolas Schier

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

2021-09-02T23:17:21+00:00

Commit 0e0345b77ac4 ("kbuild: redo fake deps at include/config/*.h") simplified the Kconfig/fixdep interaction a lot. For CONFIG_FOO_BAR_BAZ, Kconfig now touches include/config/FOO_BAR_BAZ instead of the previous include/config/foo/bar/baz.h . This commit simplifies the TRIM_UNUSED_KSYMS feature in a similar way: - delete .h suffix - delete tolower() - put everything in 1 directory For EXPORT_SYMBOL(FOO_BAR_BAZ), scripts/adjust_autoksyms.sh now touches include/ksym/FOO_BAR_BAZ instead of include/ksym/foo/bar/baz.h . This is more precise, avoiding possibly unnecessary rebuilds. EXPORT_SYMBOL(FOO_BAR_BAZ) EXPORT_SYMBOL(_FOO_BAR_BAZ) EXPORT_SYMBOL(__FOO_BAR_BAZ) were previously mapped to the same header, include/ksym/foo/bar/baz.h but now are handled separately. Signed-off-by: Masahiro Yamada

kbuild: do not include include/config/auto.conf from adjust_autoksyms.sh

2021-02-28T06:22:02+00:00

Commit cd195bc4775a ("kbuild: split adjust_autoksyms.sh in two parts") split out the code that needs include/config/auto.conf. This script no longer needs to include include/config/auto.conf. Fixes: cd195bc4775a ("kbuild: split adjust_autoksyms.sh in two parts") Signed-off-by: Masahiro Yamada

kbuild: split adjust_autoksyms.sh in two parts

2020-03-03T11:49:21+00:00

In order to prepare the ground for a build-time optimization, split adjust_autoksyms.sh into two scripts: one that generates autoksyms.h based on all currently available information (whitelist, and .mod files), and the other to inspect the diff between two versions of autoksyms.h and trigger appropriate rebuilds. Acked-by: Nicolas Pitre Tested-by: Matthias Maennich Reviewed-by: Matthias Maennich Signed-off-by: Quentin Perret Signed-off-by: Masahiro Yamada

kbuild: allow symbol whitelisting with TRIM_UNUSED_KSYMS

2020-03-03T11:49:21+00:00

CONFIG_TRIM_UNUSED_KSYMS currently removes all unused exported symbols from ksymtab. This works really well when using in-tree drivers, but cannot be used in its current form if some of them are out-of-tree. Indeed, even if the list of symbols required by out-of-tree drivers is known at compile time, the only solution today to guarantee these don't get trimmed is to set CONFIG_TRIM_UNUSED_KSYMS=n. This not only wastes space, but also makes it difficult to control the ABI usable by vendor modules in distribution kernels such as Android. Being able to control the kernel ABI surface is particularly useful to ship a unique Generic Kernel Image (GKI) for all vendors, which is a first step in the direction of getting all vendors to contribute their code upstream. As such, attempt to improve the situation by enabling users to specify a symbol 'whitelist' at compile time. Any symbol specified in this whitelist will be kept exported when CONFIG_TRIM_UNUSED_KSYMS is set, even if it has no in-tree user. The whitelist is defined as a simple text file, listing symbols, one per line. Acked-by: Jessica Yu Acked-by: Nicolas Pitre Tested-by: Matthias Maennich Reviewed-by: Matthias Maennich Signed-off-by: Quentin Perret Signed-off-by: Masahiro Yamada

kbuild: remove the first line of *.mod files

2019-07-17T17:19:31+00:00

The current format of *.mod is like this: line 1: directory path to the .ko file line 2: a list of objects linked into this module line 3: unresolved symbols (only when CONFIG_TRIM_UNUSED_KSYMS=y) Now that *.mod and *.ko are created in the same directory, the line 1 provides no valuable information. It can be derived by replacing the extension .mod with .ko. In fact, nobody uses the first line any more. Cut down the first line. Signed-off-by: Masahiro Yamada

kbuild: create *.mod with full directory path and remove MODVERDIR

2019-07-17T17:19:31+00:00

While descending directories, Kbuild produces objects for modules, but do not link final *.ko files; it is done in the modpost. To keep track of modules, Kbuild creates a *.mod file in $(MODVERDIR) for every module it is building. Some post-processing steps read the necessary information from *.mod files. This avoids descending into directories again. This mechanism was introduced in 2003 or so. Later, commit 551559e13af1 ("kbuild: implement modules.order") added modules.order. So, we can simply read it out to know all the modules with directory paths. This is easier than parsing the first line of *.mod files. $(MODVERDIR) has a flat directory structure, that is, *.mod files are named only with base names. This is based on the assumption that the module name is unique across the tree. This assumption is really fragile. Stephen Rothwell reported a race condition caused by a module name conflict: https://lkml.org/lkml/2019/5/13/991 In parallel building, two different threads could write to the same $(MODVERDIR)/*.mod simultaneously. Non-unique module names are the source of all kind of troubles, hence commit 3a48a91901c5 ("kbuild: check uniqueness of module names") introduced a new checker script. However, it is still fragile in the build system point of view because this race happens before scripts/modules-check.sh is invoked. If it happens again, the modpost will emit unclear error messages. To fix this issue completely, create *.mod with full directory path so that two threads never attempt to write to the same file. $(MODVERDIR) is no longer needed. Since modules with directory paths are listed in modules.order, Kbuild is still able to find *.mod files without additional descending. I also killed cmd_secanalysis; scripts/mod/sumversion.c computes MD4 hash for modules with MODULE_VERSION(). When CONFIG_DEBUG_SECTION_MISMATCH=y, it occurs not only in the modpost stage, but also during directory descending, where sumversion.c may parse stale *.mod files. It would emit 'No such file or directory' warning when an object consisting a module is renamed, or when a single-obj module is turned into a multi-obj module or vice versa. Signed-off-by: Masahiro Yamada Acked-by: Nicolas Pitre

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

2019-06-19T15:09:55+00:00

Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Enrico Weigelt Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman

kbuild: source include/config/auto.conf instead of ${KCONFIG_CONFIG}

2019-03-13T17:39:11+00:00

As commit 423a8155facf ("kbuild: Fix reading of .config in link-vmlinux.sh") addressed, some shells fail to perform '.' if ${KCONFIG_CONFIG} does not contain a slash at all. Instead, we can source include/config/auto.conf, which obviously contain slashes, and we do not expect its file path overridden by a user. Perhaps, the performance might be slightly better since unset CONFIG options are stripped from include/config/auto.conf. scripts/setlocalversion already works this way. Signed-off-by: Masahiro Yamada

kbuild: remove CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX

2018-05-17T13:44:57+00:00

CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX was selected by BLACKFIN, METAG. They were removed by commit 4ba66a976072 ("arch: remove blackfin port"), commit bb6fb6dfcc17 ("metag: Remove arch/metag/"), respectively. No more architecture enables CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX. Clean up the rest of scripts, and remove the Kconfig entry. Signed-off-by: Masahiro Yamada Reviewed-by: Sam Ravnborg