linux/scripts
Quentin Perret 1518c633df kbuild: allow symbol whitelisting with TRIM_UNUSED_KSYMS
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 <jeyu@kernel.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Tested-by: Matthias Maennich <maennich@google.com>
Reviewed-by: Matthias Maennich <maennich@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-03-03 20:49:21 +09:00
..
atomic locking/atomics: Use sed(1) instead of non-standard head(1) option 2019-06-25 10:17:07 +02:00
basic fixdep: remove redundant null character check 2020-03-02 21:18:19 +09:00
coccinelle mm: remove __krealloc 2020-02-04 03:05:24 +00:00
dtc kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
gcc-plugins kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
gdb scripts/gdb: fix debugging modules compiled with hot/cold partitioning 2019-11-06 08:47:50 -08:00
genksyms kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
kconfig kbuild: use KBUILD_DEFCONFIG as the fallback for DEFCONFIG_LIST 2020-03-03 20:49:21 +09:00
ksymoops
mod kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
package builddeb: split libc headers deployment out into a function 2020-01-29 01:51:30 +09:00
selinux kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
tracing treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
.gitignore TTY/Serial driver updates for 5.6-rc1 2020-01-29 10:13:27 -08:00
adjust_autoksyms.sh kbuild: allow symbol whitelisting with TRIM_UNUSED_KSYMS 2020-03-03 20:49:21 +09:00
asn1_compiler.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36 2019-05-24 17:27:11 +02:00
bin2c.c kbuild: move bin2c back to scripts/ from scripts/basic/ 2018-07-18 01:18:05 +09:00
bloat-o-meter bloat-o-meter: ignore __addressable_ symbols 2018-12-28 12:11:44 -08:00
bootgraph.pl treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 391 2019-06-05 17:37:11 +02:00
bpf_helpers_doc.py libbpf: Clean up bpf_helper_defs.h generation output 2020-01-13 17:48:13 -08:00
cc-can-link.sh
check_extable.sh
checkincludes.pl
checkkconfigsymbols.py treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
checkpatch.pl pr_warning() removal for 5.5 2019-12-09 11:48:21 -08:00
checkstack.pl scripts/checkstack.pl: Fix arm64 wrong or unknown architecture 2019-06-05 02:33:10 +09:00
checksyscalls.sh checksyscalls: fix up mq_timedreceive and stat exceptions 2019-02-19 21:27:53 +01:00
checkversion.pl
clang-version.sh kbuild: update comment block of scripts/clang-version.sh 2019-03-04 22:34:54 +09:00
cleanfile
cleanpatch
coccicheck coccicheck: return proper error code on fail 2018-08-14 08:58:56 +09:00
config
const_structs.checkpatch
decode_stacktrace.sh scripts/decode_stacktrace: Accept dash/underscore in modules 2019-07-12 11:05:41 -07:00
decodecode scripts/decodecode: set ARCH when running natively on arm/arm64 2018-12-28 12:11:44 -08:00
depmod.sh kbuild: modules_install: warn when missing System.map file 2018-09-09 09:14:07 +09:00
diffconfig
documentation-file-ref-check scripts/documentation-file-ref-check: ignore output dir 2019-06-14 14:43:01 -06:00
export_report.pl modpost: add support for symbol namespaces 2019-09-10 10:30:21 +02:00
extract_xc3028.pl treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 339 2019-06-05 17:37:07 +02:00
extract-cert.c
extract-ikconfig
extract-module-sig.pl
extract-sys-certs.pl
extract-vmlinux treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 378 2019-06-05 17:37:10 +02:00
faddr2line scripts/faddr2line: fix location of start_kernel in comment 2018-11-18 10:15:09 -08:00
file-size.sh
find-unused-docs.sh scripts/find-unused-docs: Fix massive false positives 2020-01-27 14:25:06 -07:00
gcc-goto.sh jump_label: move 'asm goto' support test to Kconfig 2019-01-06 09:46:51 +09:00
gcc-ld
gcc-plugin.sh
gcc-version.sh kbuild: clean up scripts/gcc-version.sh 2019-03-04 22:35:04 +09:00
gcc-x86_32-has-stack-protector.sh
gcc-x86_64-has-stack-protector.sh
gen_compile_commands.py gen_compile_commands: lower the entry count threshold 2019-07-27 12:18:19 +09:00
gen_ksymdeps.sh kbuild: simplify dependency generation for CONFIG_TRIM_UNUSED_KSYMS 2018-12-01 23:13:14 +09:00
get_abi.pl doc: ABI scripts: add a SPDX header file 2019-06-21 16:58:37 +02:00
get_dvb_firmware treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 61 2019-05-24 17:36:45 +02:00
get_maintainer.pl scripts/get_maintainer.pl: deprioritize old Fixes: addresses 2020-02-21 11:22:15 -08:00
gfp-translate treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
headerdep.pl
headers_check.pl
headers_install.sh kbuild: re-implement detection of CONFIG options leaked to user-space 2019-08-21 21:05:21 +09:00
insert-sys-cert.c
jobserver-exec docs, parallelism: Rearrange how jobserver reservations are made 2019-11-22 10:35:18 -07:00
kallsyms.c scripts/kallsyms: fix memory corruption caused by write over-run 2020-02-11 05:18:09 +09:00
Kbuild.include kbuild: remove *.tmp file when filechk fails 2020-01-16 00:26:22 +09:00
Kconfig.include Kbuild updates for v5.6 2020-02-01 10:01:52 -08:00
kernel-doc scripts/kernel-doc: Add support for named variable macro arguments 2019-11-07 13:17:24 -07:00
ld-version.sh
leaking_addresses.pl treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
Lindent
link-vmlinux.sh kbuild: fix mismatch between .version and include/generated/compile.h 2020-02-11 05:18:40 +09:00
Makefile kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Makefile.asm-generic kbuild: force all architectures except um to include mandatory-y 2019-03-17 12:56:32 +09:00
Makefile.build kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Makefile.clean kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Makefile.dtbinst
Makefile.extrawarn kbuild: allow Clang to find unused static inline functions for W=1 build 2019-09-09 23:55:43 +09:00
Makefile.gcc-plugins gcc-plugins: structleak: Generalize to all variable types 2019-03-04 09:29:41 -08:00
Makefile.headersinst kbuild: move headers_check rule to usr/include/Makefile 2019-11-15 00:23:10 +09:00
Makefile.host kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Makefile.kasan kasan/arm64: fix CONFIG_KASAN_SW_TAGS && KASAN_INLINE 2019-08-15 13:24:04 +01:00
Makefile.kcov treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Makefile.lib kbuild: remove unneeded semicolon at the end of cmd_dtb_check 2020-02-27 02:24:34 +09:00
Makefile.modfinal kbuild: move modkern_{c,a}flags to Makefile.lib from Makefile.build 2019-08-22 01:14:11 +09:00
Makefile.modinst kbuild: modinst: read modules.order instead of $(MODVERDIR)/*.mod 2019-07-17 22:39:27 +09:00
Makefile.modpost kbuild: remove 'Building modules, stage 2.' log 2020-01-16 01:18:35 +09:00
Makefile.modsign kbuild: modsign: read modules.order instead of $(MODVERDIR)/*.mod 2019-07-17 22:39:27 +09:00
Makefile.package kbuild: Add make dir-pkg build option 2019-11-11 20:10:01 +09:00
Makefile.ubsan ubsan: Remove vla bound checks. 2019-05-06 11:12:09 -07:00
makelst
markup_oops.pl treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 373 2019-06-05 17:37:10 +02:00
mkcompile_h kbuild: remove the owner check in mkcompile_h 2020-03-02 21:18:19 +09:00
mkmakefile kbuild: get rid of $(realpath ...) from scripts/mkmakefile 2019-08-29 23:54:29 +09:00
mksysmap
mkuboot.sh
module-common.lds
modules-check.sh kbuild: get rid of kernel/ prefix from in-tree modules.{order,builtin} 2019-07-17 22:39:27 +09:00
namespace.pl namespace: fix namespace.pl script to support relative paths 2019-10-05 15:29:49 +09:00
nsdeps scripts/nsdeps: support nsdeps for external module builds 2019-11-11 20:10:01 +09:00
objdiff treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 199 2019-05-30 11:29:23 -07:00
parse-maintainers.pl
patch-kernel
profile2linkerlist.pl
prune-kernel
recordmcount.c ARM: 8950/1: ftrace/recordmcount: filter relocation types 2020-01-19 16:08:25 +00:00
recordmcount.h recordmcount: Fix nop_mcount() function 2019-10-12 20:49:33 -04:00
recordmcount.pl treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
setlocalversion scripts: setlocalversion: replace backquote to dollar parenthesis 2019-11-11 20:10:01 +09:00
show_delta treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 438 2019-06-05 17:37:17 +02:00
sign-file.c
sorttable.c scripts/sorttable: Implement build-time ORC unwind table sorting 2019-12-13 10:47:58 +01:00
sorttable.h scripts/sorttable: Implement build-time ORC unwind table sorting 2019-12-13 10:47:58 +01:00
spdxcheck-test.sh scripts: add spdxcheck.py self test 2018-12-28 12:11:44 -08:00
spdxcheck.py spdxcheck.py: fix directory structures 2019-06-01 15:51:31 -07:00
spelling.txt scripts/spelling.txt: add "issus" typo 2020-01-31 10:30:36 -08:00
sphinx-pre-install Allow git builds of Sphinx 2020-02-05 10:33:44 -07:00
split-man.pl
stackdelta
stackusage
subarch.include selftests: add headers_install to lib.mk 2018-09-05 08:12:09 -06:00
tags.sh kbuild: add a flag to force absolute path for srctree 2019-07-11 00:05:09 +09:00
tools-support-relr.sh scripts/tools-support-relr.sh: un-quote variables 2019-11-13 10:52:05 +00:00
unifdef.c unifdef: use memcpy instead of strncpy 2018-11-30 14:45:01 -08:00
ver_linux scripts/ver_linux: add Bison and Flex to the checklist 2019-11-11 20:10:01 +09:00
xen-hypercalls.sh
xz_wrap.sh