renegade-project/linux-next
2
0
Fork 0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-15 16:53:54 +08:00
Code
1fdd7433a9
linux-next/scripts
History
Yonghong Song 1fdd7433a9 kbuild: add an elfnote for whether vmlinux is built with lto 
Currently, clang LTO built vmlinux won't work with pahole.
LTO introduced cross-cu dwarf tag references and broke
current pahole model which handles one cu as a time.
The solution is to merge all cu's as one pahole cu as in [1].
We would like to do this merging only if cross-cu dwarf
references happens. The LTO build mode is a pretty good
indication for that.

In earlier version of this patch ([2]), clang flag
-grecord-gcc-switches is proposed to add to compilation flags
so pahole could detect "-flto" and then merging cu's.
This will increate the binary size of 1% without LTO though.

Arnaldo suggested to use a note to indicate the vmlinux
is built with LTO. Such a cheap way to get whether the vmlinux
is built with LTO or not helps pahole but is also useful
for tracing as LTO may inline/delete/demote global functions,
promote static functions, etc.

So this patch added an elfnote with a new type LINUX_ELFNOTE_LTO_INFO.
The owner of the note is "Linux".

With gcc 8.4.1 and clang trunk, without LTO, I got
  $ readelf -n vmlinux
  Displaying notes found in: .notes
    Owner                Data size        Description
  ...
    Linux                0x00000004       func
     description data: 00 00 00 00
  ...
With "readelf -x ".notes" vmlinux", I can verify the above "func"
with type code 0x101.

With clang thin-LTO, I got the same as above except the following:
     description data: 01 00 00 00
which indicates the vmlinux is built with LTO.

  [1] https://lore.kernel.org/bpf/20210325065316.3121287-1-yhs@fb.com/
  [2] https://lore.kernel.org/bpf/20210331001623.2778934-1-yhs@fb.com/

Suggested-by: Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM/Clang v12.0.0-rc4 (x86-64)
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-04-25 05:25:42 +09:00
..
atomic locking/atomics: Regenerate the atomics-check SHA1's 2020-11-07 13:20:41 +01:00
basic kbuild: introduce hostprogs-always-y and userprogs-always-y 2020-08-10 01:32:59 +09:00
clang-tools gen_compile_commands: prune some directories 2021-02-16 22:23:56 +09:00
coccinelle of: Remove of_dev_{get,put}() 2021-02-12 19:23:39 -06:00
dtc Devicetree fixes for v5.12-rc: 2021-03-05 12:12:28 -08:00
dummy-tools kbuild: check the minimum assembler version in Kconfig 2021-04-25 05:14:41 +09:00
gcc-plugins kbuild: rebuild GCC plugins when the compiler is upgraded 2021-03-11 14:40:50 +09:00
gdb scripts/gdb: fix list_for_each 2021-02-26 09:41:05 -08:00
genksyms genksyms: remove useless case DOTS 2021-02-16 12:01:45 +09:00
kconfig kconfig: unify rule of config, menuconfig, nconfig, gconfig, xconfig 2021-02-24 15:12:06 +09:00
ksymoops
mod kbuild: add an elfnote for whether vmlinux is built with lto 2021-04-25 05:25:42 +09:00
package builddeb: Fix rootless build in setuid/setgid directory 2020-11-02 11:31:00 +09:00
selinux scripts/selinux,selinux: update mdp to enable policy capabilities 2020-08-17 20:42:00 -04:00
tracing tweewide: Fix most Shebang lines 2020-12-08 23:30:04 +09:00
.gitignore kbuild: preprocess module linker script 2020-09-25 00:36:41 +09:00
adjust_autoksyms.sh kbuild: do not include include/config/auto.conf from adjust_autoksyms.sh 2021-02-28 15:22:02 +09:00
as-version.sh kbuild: check the minimum assembler version in Kconfig 2021-04-25 05:14:41 +09:00
asn1_compiler.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36 2019-05-24 17:27:11 +02:00
bin2c.c
bloat-o-meter scripts: switch explicitly to Python 3 2021-01-22 06:34:44 +09:00
bootgraph.pl treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 391 2019-06-05 17:37:11 +02:00
bpf_helpers_doc.py bpf: Add a bpf_sock_from_file helper 2020-12-04 22:32:40 +01:00
cc-can-link.sh
cc-version.sh kbuild: collect minimum tool versions into scripts/min-tool-version.sh 2021-04-25 05:14:26 +09:00
check_extable.sh
check-sysctl-docs docs: add a script to check sysctl docs 2020-02-25 03:35:16 -07:00
checkincludes.pl
checkkconfigsymbols.py kconfig: remove '---help---' support 2020-08-14 13:30:03 +09:00
checkpatch.pl checkpatch: do not apply "initialise globals to 0" check to BPF progs 2021-02-26 09:41:04 -08:00
checkstack.pl scripts/checkstack.pl: fix arm sp regex 2020-05-26 00:03:16 +09:00
checksyscalls.sh checksyscalls: fix up mq_timedreceive and stat exceptions 2019-02-19 21:27:53 +01:00
checkversion.pl
cleanfile
cleanpatch
coccicheck scripts: coccicheck: Correct usage of make coccicheck 2020-12-24 12:59:43 +01:00
config kconfig: config script: add a little user help 2021-01-04 10:38:11 +09:00
const_structs.checkpatch const_structs.checkpatch: add pinctrl_ops and pinmux_ops 2020-10-16 11:11:21 -07:00
decode_stacktrace.sh scripts/decode_stacktrace.sh: guess path to vmlinux by release name 2020-08-07 11:33:21 -07:00
decodecode scripts/decodecode: add the capability to supply the program counter 2020-10-13 18:38:26 -07:00
depmod.sh depmod: handle the case of /sbin/depmod without /sbin in PATH 2021-01-01 12:26:39 -08:00
dev-needs.sh scripts/dev-needs: Add script to list device dependencies 2020-09-04 18:19:37 +02:00
diffconfig scripts: switch explicitly to Python 3 2021-01-22 06:34:44 +09:00
documentation-file-ref-check scripts: documentation-file-ref-check: Add line break before exit 2020-04-15 15:13:13 -06:00
export_report.pl modpost: move the namespace field in Module.symvers last 2020-03-17 08:59:03 +09:00
extract_xc3028.pl treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 339 2019-06-05 17:37:07 +02:00
extract-cert.c extract-cert: add static to local data 2020-08-18 20:16:46 +09:00
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
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-x86_32-has-stack-protector.sh
gcc-x86_64-has-stack-protector.sh
gen_autoksyms.sh kbuild: fix UNUSED_KSYMS_WHITELIST for Clang LTO 2021-02-28 15:19:21 +09:00
gen_ksymdeps.sh
generate_initcall_order.pl init: lto: ensure initcall ordering 2021-01-14 08:21:09 -08:00
get_abi.pl tweewide: Fix most Shebang lines 2020-12-08 23:30:04 +09:00
get_dvb_firmware treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 61 2019-05-24 17:36:45 +02:00
get_feat.pl scripts: get_feat.pl: reduce table width for all features output 2020-12-04 14:34:27 -07:00
get_maintainer.pl get_maintainer: exclude MAINTAINERS file(s) from --git-fallback 2020-10-16 11:11:19 -07:00
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 Merge branch 'work.fdpic' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 13:29:39 -07:00
insert-sys-cert.c
jobserver-exec kbuild: remove PYTHON variable 2021-02-01 10:37:19 +09:00
kallsyms.c kallsyms: fix nonconverging kallsyms table with lld 2021-02-05 17:53:28 +09:00
Kbuild.include kbuild: split cc-option and friends to scripts/Makefile.compiler 2021-04-25 05:09:32 +09:00
Kconfig.include kbuild: check the minimum assembler version in Kconfig 2021-04-25 05:14:41 +09:00
kernel-doc scripts: kernel-doc: fix array element capture in pointer-to-func parsing 2021-02-22 14:20:36 -07:00
ld-version.sh kbuild: collect minimum tool versions into scripts/min-tool-version.sh 2021-04-25 05:14:26 +09:00
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: apply fixdep logic to link-vmlinux.sh 2021-04-25 05:12:32 +09:00
Makefile scripts: set proper OpenSSL include dir also for sign-file 2021-02-15 01:54:11 +09:00
Makefile.asm-generic kbuild: prefix $(srctree)/ to some included Makefiles 2021-03-15 19:20:48 +09:00
Makefile.build kbuild: rename multi-used-* to multi-obj-* 2021-04-25 05:12:34 +09:00
Makefile.clean kbuild: prefix $(srctree)/ to some included Makefiles 2021-03-15 19:20:48 +09:00
Makefile.compiler kbuild: split cc-option and friends to scripts/Makefile.compiler 2021-04-25 05:09:32 +09:00
Makefile.dtbinst kbuild: prefix $(srctree)/ to some included Makefiles 2021-03-15 19:20:48 +09:00
Makefile.extrawarn Makefile.extrawarn: remove -Wnested-externs warning 2020-12-08 23:30:05 +09:00
Makefile.gcc-plugins gcc-plugins/stackleak: Use asm instrumentation to avoid useless register saving 2020-06-24 07:48:28 -07:00
Makefile.headersinst kbuild: prefix $(srctree)/ to some included Makefiles 2021-03-15 19:20:48 +09:00
Makefile.host kbuild: sort hostprogs before passing it to ifneq 2020-08-10 01:32:59 +09:00
Makefile.kasan kbuild: move CFLAGS_{KASAN,UBSAN,KCSAN} exports to relevant Makefiles 2020-09-25 00:36:50 +09:00
Makefile.kcov kbuild: include scripts/Makefile.* only when relevant CONFIG is enabled 2020-08-10 01:32:59 +09:00
Makefile.kcsan Kbuild updates for v5.10 2020-10-22 13:13:57 -07:00
Makefile.lib kbuild: move $(strip ) to suffix-search definition 2021-04-25 05:12:42 +09:00
Makefile.modfinal kbuild: lto: postpone objtool 2021-02-23 12:46:57 -08:00
Makefile.modinst kbuild: add support for zstd compressed modules 2021-04-25 05:25:06 +09:00
Makefile.modpost kbuild: fix false-positive modpost warning when all symbols are trimmed 2021-04-25 05:17:53 +09:00
Makefile.package kbuild: fix broken builds because of GZIP,BZIP2,LZOP variables 2020-06-11 20:14:41 +09:00
Makefile.ubsan ubsan: remove overflow checks 2021-02-26 09:41:05 -08:00
Makefile.userprogs kbuild: add infrastructure to build userspace programs 2020-05-17 18:52:01 +09:00
makelst
markup_oops.pl treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 373 2019-06-05 17:37:10 +02:00
min-tool-version.sh kbuild: collect minimum tool versions into scripts/min-tool-version.sh 2021-04-25 05:14:26 +09:00
mkcompile_h kbuild: Use uname for LINUX_COMPILE_HOST detection 2020-10-21 00:46:04 +09:00
mkmakefile kbuild: get rid of $(realpath ...) from scripts/mkmakefile 2019-08-29 23:54:29 +09:00
mksysmap mksysmap: Fix the mismatch of '.L' symbols in System.map 2020-06-06 23:39:20 +09:00
mkuboot.sh
module.lds.S Modules updates for v5.12 2021-02-23 10:15:33 -08:00
modules-check.sh kbuild: check module name conflict for external modules as well 2021-04-25 05:22:42 +09:00
nsdeps kbuild: do not use scripts/ld-version.sh for checking spatch version 2020-12-12 18:31:29 +01:00
objdiff treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 199 2019-05-30 11:29:23 -07:00
parse-maintainers.pl parse-maintainers: Do not sort section content by default 2020-03-26 15:08:27 -07:00
patch-kernel
profile2linkerlist.pl
prune-kernel
recordmcount.c ftrace: Have recordmcount use w8 to read relp->r_info in arm64_is_fake_mcount 2021-03-02 17:27:18 -05:00
recordmcount.h recordmcount: support >64k sections 2020-06-16 21:21:00 -04:00
recordmcount.pl scripts/recordmcount.pl: support big endian for ARCH sh 2021-02-13 11:42:40 -08:00
setlocalversion scripts/setlocalversion: make git describe output more reliable 2020-09-25 02:28:12 +09:00
show_delta tweewide: Fix most Shebang lines 2020-12-08 23:30:04 +09:00
sign-file.c
sorttable.c s390/kernel: expand exception table logic to allow new handling options 2020-07-20 10:55:50 +02:00
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: Use Python 3 2021-01-27 14:50:12 +01:00
spelling.txt scripts/spelling.txt: add more spellings to spelling.txt 2021-02-24 13:38:26 -08:00
sphinx-pre-install Docs: drop Python 2 support 2021-02-01 17:17:14 -07:00
split-man.pl tweewide: Fix most Shebang lines 2020-12-08 23:30:04 +09:00
stackdelta
stackusage
subarch.include
syscallhdr.sh scripts: add generic syscallhdr.sh 2021-02-22 08:22:04 +09:00
syscalltbl.sh scripts: add generic syscalltbl.sh 2021-02-22 08:22:03 +09:00
tags.sh Merge branch 'locking/urgent' into locking/core, to pick up fixes 2020-10-09 08:55:17 +02:00
tools-support-relr.sh scripts/tools-support-relr.sh: un-quote variables 2019-11-13 10:52:05 +00:00
unifdef.c
ver_linux ver_linux: Eliminate duplicate code in ldconfig processing logic 2021-01-27 14:54:42 +01:00
xen-hypercalls.sh
xz_wrap.sh kbuild: add variables for compression tools 2020-06-06 23:42:01 +09:00