linux/scripts
Nathan Chancellor 9c1b86f8ce kbuild: raise the minimum supported version of LLVM to 13.0.1
Patch series "Bump the minimum supported version of LLVM to 13.0.1".

This series bumps the minimum supported version of LLVM for building the
kernel to 13.0.1.  The first patch does the bump and all subsequent
patches clean up all the various workarounds and checks for earlier
versions.

Quoting the first patch's commit message for those that were only on CC
for the clean ups:

  When __builtin_mul_overflow() has arguments that differ in terms of
  signedness and width, LLVM may generate a libcall to __muloti4 because
  it performs the checks in terms of 65-bit multiplication. This issue
  becomes harder to hit (but still possible) after LLVM 12.0.0, which
  includes a special case for matching widths but different signs.

  To gain access to this special case, which the kernel can take advantage
  of when calls to __muloti4 appear, bump the minimum supported version of
  LLVM for building the kernel to 13.0.1. 13.0.1 was chosen because there
  is minimal impact to distribution support while allowing a few more
  workarounds to be dropped in the kernel source than if 12.0.0 were
  chosen. Looking at container images of up to date distribution versions:

    archlinux:latest              clang version 16.0.6
    debian:oldoldstable-slim      clang version 7.0.1-8+deb10u2 (tags/RELEASE_701/final)
    debian:oldstable-slim         Debian clang version 11.0.1-2
    debian:stable-slim            Debian clang version 14.0.6
    debian:testing-slim           Debian clang version 16.0.6 (19)
    debian:unstable-slim          Debian clang version 16.0.6 (19)
    fedora:38                     clang version 16.0.6 (Fedora 16.0.6-3.fc38)
    fedora:latest                 clang version 17.0.6 (Fedora 17.0.6-1.fc39)
    fedora:rawhide                clang version 17.0.6 (Fedora 17.0.6-1.fc40)
    opensuse/leap:latest          clang version 15.0.7
    opensuse/tumbleweed:latest    clang version 17.0.6
    ubuntu:focal                  clang version 10.0.0-4ubuntu1
    ubuntu:latest                 Ubuntu clang version 14.0.0-1ubuntu1.1
    ubuntu:rolling                Ubuntu clang version 16.0.6 (15)
    ubuntu:devel                  Ubuntu clang version 17.0.6 (3)

  The only distribution that gets left behind is Debian Bullseye, as the
  default version is 11.0.1; other distributions either have a newer
  version than 13.0.1 or one older than the current minimum of 11.0.0.
  Debian has easy access to more recent LLVM versions through
  apt.llvm.org, so this is not as much of a concern. There are also the
  kernel.org LLVM toolchains, which should work with distributions with
  glibc 2.28 and newer.

  Another benefit of slimming up the number of supported versions of LLVM
  for building the kernel is reducing the build capacity needed to support
  a matrix that builds with each supported version, which allows a matrix
  to reallocate the freed up build capacity towards something else, such
  as more configuration combinations.

This passes my build matrix with all supported versions.

This is based on Andrew's mm-nonmm-unstable to avoid trivial conflicts
with my series to update the LLVM links across the repository [1] but I
can easily rebase it to linux-kbuild if Masahiro would rather these
patches go through there (and defer the conflict resolution to the merge
window).

[1]: https://lore.kernel.org/20240109-update-llvm-links-v1-0-eb09b59db071@kernel.org/


This patch (of 11):

When __builtin_mul_overflow() has arguments that differ in terms of
signedness and width, LLVM may generate a libcall to __muloti4 because it
performs the checks in terms of 65-bit multiplication.  This issue becomes
harder to hit (but still possible) after LLVM 12.0.0, which includes a
special case for matching widths but different signs.

To gain access to this special case, which the kernel can take advantage
of when calls to __muloti4 appear, bump the minimum supported version of
LLVM for building the kernel to 13.0.1.  13.0.1 was chosen because there
is minimal impact to distribution support while allowing a few more
workarounds to be dropped in the kernel source than if 12.0.0 were chosen.
Looking at container images of up to date distribution versions:

  archlinux:latest              clang version 16.0.6
  debian:oldoldstable-slim      clang version 7.0.1-8+deb10u2 (tags/RELEASE_701/final)
  debian:oldstable-slim         Debian clang version 11.0.1-2
  debian:stable-slim            Debian clang version 14.0.6
  debian:testing-slim           Debian clang version 16.0.6 (19)
  debian:unstable-slim          Debian clang version 16.0.6 (19)
  fedora:38                     clang version 16.0.6 (Fedora 16.0.6-3.fc38)
  fedora:latest                 clang version 17.0.6 (Fedora 17.0.6-1.fc39)
  fedora:rawhide                clang version 17.0.6 (Fedora 17.0.6-1.fc40)
  opensuse/leap:latest          clang version 15.0.7
  opensuse/tumbleweed:latest    clang version 17.0.6
  ubuntu:focal                  clang version 10.0.0-4ubuntu1
  ubuntu:latest                 Ubuntu clang version 14.0.0-1ubuntu1.1
  ubuntu:rolling                Ubuntu clang version 16.0.6 (15)
  ubuntu:devel                  Ubuntu clang version 17.0.6 (3)

The only distribution that gets left behind is Debian Bullseye, as the
default version is 11.0.1; other distributions either have a newer version
than 13.0.1 or one older than the current minimum of 11.0.0.  Debian has
easy access to more recent LLVM versions through apt.llvm.org, so this is
not as much of a concern.  There are also the kernel.org LLVM toolchains,
which should work with distributions with glibc 2.28 and newer.

Another benefit of slimming up the number of supported versions of LLVM
for building the kernel is reducing the build capacity needed to support a
matrix that builds with each supported version, which allows a matrix to
reallocate the freed up build capacity towards something else, such as
more configuration combinations.

Link: https://lkml.kernel.org/r/20240125-bump-min-llvm-ver-to-13-0-1-v1-0-f5ff9bda41c5@kernel.org
Closes: https://github.com/ClangBuiltLinux/linux/issues/1975
Link: https://github.com/llvm/llvm-project/issues/38013
Link: 3203143f13
Link: https://mirrors.edge.kernel.org/pub/tools/llvm/
Link: https://lkml.kernel.org/r/20240125-bump-min-llvm-ver-to-13-0-1-v1-1-f5ff9bda41c5@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: "Aneesh Kumar K.V (IBM)" <aneesh.kumar@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Conor Dooley <conor@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22 15:38:54 -08:00
..
atomic locking/atomic: Add generic support for sync_try_cmpxchg() and its fallback 2023-10-09 18:14:15 +02:00
basic kbuild: implement CONFIG_TRIM_UNUSED_KSYMS without recursion 2023-06-22 21:21:06 +09:00
clang-tools gen_compile_commands: fix invalid escape sequence warning 2024-02-15 06:57:19 +09:00
coccinelle coccinelle: device_attr_show: simplify patch case 2024-01-20 21:56:11 +01:00
dtc dt: dt-extract-compatibles: Don't follow symlinks when walking tree 2023-11-09 11:56:39 -06:00
dummy-tools kbuild: dummy-tools: pretend we understand -fpatchable-function-entry 2023-11-01 23:24:56 +09:00
gcc-plugins gcc-plugins: randstruct: Update code comment in relayout_struct() 2023-11-27 16:30:05 -08:00
gdb Kbuild updates for v6.8 2024-01-18 17:57:07 -08:00
genksyms genksyms: use getopt_long() unconditionally 2023-11-28 11:22:50 +09:00
kconfig kconfig: initialize sym->curr.tri to 'no' for all symbol types again 2024-01-31 23:59:42 +09:00
ksymoops
mod modpost: trim leading spaces when processing source files list 2024-02-15 06:57:19 +09:00
package kbuild: rpm-pkg: simplify installkernel %post 2024-01-31 23:24:27 +09:00
selinux selinux: remove runtime disable message in the install_policy.sh script 2022-09-20 14:12:25 -04:00
tracing tracing: Always use canonical ftrace path 2023-02-18 14:34:09 -05:00
.gitignore rust: support running Rust documentation tests as KUnit ones 2023-07-19 09:32:53 -06:00
as-version.sh kbuild: Update assembler calls to use proper flags and language target 2023-01-26 12:41:38 +09:00
asn1_compiler.c ASN.1: Fix check for strdup() success 2023-04-21 08:58:00 -07:00
bloat-o-meter scripts/bloat-o-meter: count weak symbol sizes 2023-08-21 13:46:25 -07:00
bootgraph.pl
bpf_doc.py bpf, docs: Fix invalid escape sequence warnings in bpf_doc.py 2023-08-31 13:56:31 +02:00
cc-can-link.sh
cc-version.sh scripts: Remove ICC-related dead code 2023-04-24 10:18:32 -07:00
check_extable.sh scripts: check_extable: fix typo in user error message 2021-09-08 11:50:28 -07:00
check-git kbuild: use git-archive for source package creation 2023-03-16 22:46:12 +09:00
check-sysctl-docs sysctl: Remove register_sysctl_table 2023-05-23 21:43:26 -07:00
check-uapi.sh check-uapi: Introduce check-uapi.sh 2023-12-29 22:25:20 +09:00
checkdeclares.pl scripts: make some scripts executable 2021-08-10 09:13:25 +09:00
checkincludes.pl
checkkconfigsymbols.py scripts: handle BrokenPipeError for python scripts 2023-01-26 12:43:33 +09:00
checkpatch.pl Char/Misc and other Driver changes for 6.8-rc1 2024-01-17 16:47:17 -08:00
checkstack.pl scripts/checkstack.pl: fix no space expression between sp and offset 2023-12-29 12:22:28 -08:00
checksyscalls.sh checksyscalls: ignore fstat to silence build warning on LoongArch 2023-03-23 17:18:32 -07:00
checkversion.pl scripts: checkversion: modernize linux/version.h search strings 2021-08-05 20:55:39 +09:00
cleanfile
cleanpatch
coccicheck scripts: coccicheck: Use /usr/bin/env 2023-02-25 20:11:06 +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 xattr_handler 2023-10-12 17:14:11 +02:00
decode_stacktrace.sh scripts/decode_stacktrace.sh: optionally use LLVM utilities 2024-01-12 15:20:46 -08:00
decodecode scripts/decodecode: add support for LoongArch 2023-12-29 12:22:25 -08:00
depmod.sh kbuild: move depmod rule to scripts/Makefile.modinst 2023-08-29 22:38:23 +09:00
dev-needs.sh scripts/dev-needs: Add script to list device dependencies 2020-09-04 18:19:37 +02:00
diffconfig scripts: handle BrokenPipeError for python scripts 2023-01-26 12:43:33 +09:00
documentation-file-ref-check scripts: documentation-file-ref-check: fix bpf selftests path 2021-10-26 09:42:29 -06:00
export_report.pl
extract_xc3028.pl
extract-ikconfig scripts/extract-ikconfig: add zstd compression support 2022-08-29 13:58:47 +09:00
extract-module-sig.pl
extract-sys-certs.pl
extract-vmlinux
faddr2line scripts/faddr2line: Skip over mapping symbols in output from readelf 2023-10-23 08:36:46 -07:00
file-size.sh
find-unused-docs.sh
gcc-x86_32-has-stack-protector.sh x86/stackprotector/32: Make the canary into a regular percpu variable 2021-03-08 13:19:05 +01:00
gcc-x86_64-has-stack-protector.sh
gen-randstruct-seed.sh randstruct: Move seed generation into scripts/basic/ 2022-05-08 01:33:07 -07:00
generate_initcall_order.pl init: lto: ensure initcall ordering 2021-01-14 08:21:09 -08:00
generate_rust_analyzer.py scripts: generate_rust_analyzer: provide cfgs for core and alloc 2023-08-20 22:54:32 +02:00
generate_rust_target.rs LoongArch: Enable initial Rust support 2024-01-17 12:43:00 +08:00
get_abi.pl scripts/get_abi.pl: ignore some temp files 2024-01-03 14:02:17 -07:00
get_dvb_firmware
get_feat.pl scripts: get_feat.pl: use /usr/bin/env to find perl 2022-06-30 12:22:17 -06:00
get_maintainer.pl get_maintainer: remove stray punctuation when cleaning file emails 2023-12-31 10:57:42 -08:00
gfp-translate scripts: fix the gfp flags header path in gfp-translate 2023-06-19 13:19:32 -07:00
git.orderFile scripts: Introduce a default git.orderFile 2023-12-29 22:25:20 +09:00
head-object-list.txt scripts: clean up IA-64 code 2023-12-03 18:51:48 +09:00
headerdep.pl
headers_install.sh hexagon: Remove CONFIG_HEXAGON_ARCH_VERSION from uapi header 2023-11-23 10:38:58 +01:00
insert-sys-cert.c
install.sh kbuild: factor out the common installation code into scripts/install.sh 2022-05-11 21:45:53 +09:00
jobserver-exec scripts: support GNU make 4.4 in jobserver-exec 2023-01-16 20:15:20 +09:00
kallsyms.c scripts/kallsyms: Fix build failure by setting errno before calling getline() 2023-07-29 15:57:32 +09:00
Kbuild.include kbuild: replace $(dot-target).tmp in filechk with $(tmp-target) 2023-01-22 23:43:33 +09:00
Kconfig.include kbuild: Update assembler calls to use proper flags and language target 2023-01-26 12:41:38 +09:00
kernel-doc Another moderately busy cycle for documentation, including: 2024-01-11 19:46:52 -08:00
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 leaking_addresses: also skip canonical ftrace path 2023-03-29 06:52:08 -04:00
Lindent
link-vmlinux.sh kbuild: Fix changing ELF file type for output of gen_btf for big endian 2024-02-15 06:56:40 +09:00
Makefile rust: support running Rust documentation tests as KUnit ones 2023-07-19 09:32:53 -06:00
Makefile.asm-generic kbuild: add kbuild-file macro 2022-11-22 23:40:02 +09:00
Makefile.btf kbuild: avoid too many execution of scripts/pahole-flags.sh 2023-10-28 21:10:08 +09:00
Makefile.build rust: Suppress searching builtin sysroot 2023-12-14 20:14:01 +01:00
Makefile.clang Kbuild updates for v6.5 2023-07-01 09:24:31 -07:00
Makefile.clean kbuild: make clean rule robust against too long argument error 2023-06-25 23:12:20 +09:00
Makefile.compiler Kbuild updates for v6.5 2023-07-01 09:24:31 -07:00
Makefile.debug Makefile.debug: support for -gz=zstd 2022-11-21 10:18:39 +09:00
Makefile.defconf kbuild: defconf: use SRCARCH to find merged configs 2024-01-28 01:13:37 +09:00
Makefile.dtbinst kbuild: Support flat DTBs install 2023-06-21 07:51:08 -06:00
Makefile.extrawarn Makefile: Enable -Wstringop-overflow globally 2024-01-21 17:45:31 -06:00
Makefile.gcc-plugins gcc-plugins: Undefine LATENT_ENTROPY_PLUGIN when plugin disabled for a file 2022-08-16 12:25:53 -07:00
Makefile.headersinst kbuild: prefix $(srctree)/ to some included Makefiles 2021-03-15 19:20:48 +09:00
Makefile.host rust: Respect HOSTCC when linking for host 2023-10-14 18:26:28 +09:00
Makefile.kasan kasan: remove hwasan-kernel-mem-intrinsic-prefix=1 for clang-14 2023-04-18 16:29:43 -07:00
Makefile.kcov kbuild: include scripts/Makefile.* only when relevant CONFIG is enabled 2020-08-10 01:32:59 +09:00
Makefile.kcsan kcsan: Ignore GCC 11+ warnings about TSan runtime support 2021-12-09 16:42:27 -08:00
Makefile.kmsan kmsan: add KMSAN runtime core 2022-10-03 14:03:19 -07:00
Makefile.lib kbuild: determine base DTB by suffix 2023-12-10 15:34:37 +09:00
Makefile.modfinal kbuild: remove ARCH_POSTLINK from module builds 2023-10-28 21:10:08 +09:00
Makefile.modinst kbuild: Use CRC32 and a 1MiB dictionary for XZ compressed modules 2023-09-25 16:01:05 +09:00
Makefile.modpost linux/export.h: make <linux/export.h> independent of CONFIG_MODULES 2023-07-25 00:59:32 +09:00
Makefile.package kbuild: deb-pkg: remove the fakeroot builds support 2023-12-10 15:34:37 +09:00
Makefile.randstruct randstruct: Enable Clang support 2022-05-08 01:33:07 -07:00
Makefile.ubsan ubsan: Tighten UBSAN_BOUNDS on GCC 2023-05-16 13:57:14 -07:00
Makefile.userprogs kbuild: support 'userldlibs' syntax 2023-11-01 23:26:01 +09:00
Makefile.vdsoinst kbuild: fix build ID symlinks to installed debug VDSO files 2023-12-23 23:24:03 +09:00
Makefile.vmlinux x86/retpoline: Make sure there are no unconverted return thunks due to KCSAN 2023-10-20 13:02:23 +02:00
Makefile.vmlinux_o x86/srso: Fix unret validation dependencies 2023-10-20 11:46:59 +02:00
makelst
markup_oops.pl
min-tool-version.sh kbuild: raise the minimum supported version of LLVM to 13.0.1 2024-02-22 15:38:54 -08:00
misc-check kbuild: make W=1 warn files that are tracked but ignored by git 2023-01-22 23:43:33 +09:00
mkcompile_h Revert "kbuild: Make scripts/compile.h when sh != bash" 2022-09-29 04:40:15 +09:00
mksysmap kallsyms: ignore ARMv4 thunks along with others 2024-02-15 22:44:56 +09:00
mkuboot.sh
module.lds.S arm64: unwind: add asynchronous unwind tables to kernel and modules 2022-11-09 18:06:35 +00:00
modules-check.sh kbuild: change module.order to list *.o instead of *.ko 2022-12-14 15:42:40 +09:00
nsdeps scripts/nsdeps: adjust to the format change of *.mod files 2022-06-08 20:14:13 +09:00
objdiff kbuild: clean .tmp_* pattern by make clean 2022-06-05 06:20:57 +09:00
objdump-func scripts/objdump-func: Support multiple functions 2023-04-14 16:08:28 +02:00
orc_hash.sh x86/unwind/orc: Add ELF section with ORC version identifier 2023-06-16 17:17:42 +02:00
pahole-version.sh kbuild: Add CONFIG_PAHOLE_VERSION 2022-02-02 11:19:33 +01:00
parse-maintainers.pl
patch-kernel
profile2linkerlist.pl
prune-kernel scripts/prune-kernel: Use kernel-install if available 2022-05-11 21:46:38 +09:00
recordmcount.c scripts: clean up IA-64 code 2023-12-03 18:51:48 +09:00
recordmcount.h recordmcount: Correct st_shndx handling 2021-06-18 09:09:17 -04:00
recordmcount.pl scripts: clean up IA-64 code 2023-12-03 18:51:48 +09:00
relocs_check.sh powerpc: Move script to check relocations at compile time in scripts/ 2023-04-19 07:46:31 -07:00
remove-stale-files kbuild: rpm-pkg: generate kernel.spec in rpmbuild/SPECS/ 2023-10-03 20:49:09 +09:00
rust_is_available_bindgen_libclang.h scripts: add rust_is_available.sh 2022-09-28 09:02:06 +02:00
rust_is_available_test.py kbuild: rust_is_available: add test suite 2023-08-10 01:18:34 +02:00
rust_is_available.sh kbuild: rust_is_available: check that output looks as expected 2023-08-10 01:18:34 +02:00
rustdoc_test_builder.rs rust: support running Rust documentation tests as KUnit ones 2023-07-19 09:32:53 -06:00
rustdoc_test_gen.rs rust: support running Rust documentation tests as KUnit ones 2023-07-19 09:32:53 -06:00
setlocalversion scripts/setlocalversion: also consider annotated tags of the form vx.y.z-${file_localversion} 2023-08-08 01:08:54 +09:00
show_delta scripts/show_delta: add __main__ judgement before main code 2023-10-18 14:43:23 -07:00
sign-file.c sign-file: Fix incorrect return values check 2023-12-13 12:55:11 -08:00
sorttable.c LoongArch: extable: Add type and data fields 2022-12-14 08:36:11 +08:00
sorttable.h x86,objtool: Split UNWIND_HINT_EMPTY in two 2023-03-23 23:18:58 +01:00
spdxcheck-test.sh docs: move Linux logo into a new images folder 2022-06-01 09:32:45 -06:00
spdxcheck.py scripts/spdxcheck: Put excluded files and directories into a separate file 2022-05-18 15:34:33 +02:00
spdxexclude scripts/spdxcheck: Exclude top-level README 2022-05-18 15:35:42 +02:00
spelling.txt scripts/spelling.txt: add more spellings to spelling.txt 2023-12-10 17:21:33 -08:00
sphinx-pre-install docs: Raise the minimum Sphinx requirement to 2.4.4 2023-12-15 08:36:33 -07:00
split-man.pl tweewide: Fix most Shebang lines 2020-12-08 23:30:04 +09:00
stackdelta
stackusage
subarch.include LoongArch: Add build infrastructure 2022-06-03 20:09:27 +08:00
syscallhdr.sh scripts: check duplicated syscall number in syscall table 2021-07-09 04:00:39 +09:00
syscallnr.sh scripts: make some scripts executable 2021-08-10 09:13:25 +09:00
syscalltbl.sh scripts: check duplicated syscall number in syscall table 2021-07-09 04:00:39 +09:00
tags.sh scripts/tags.sh: remove find_sources 2024-01-04 17:01:15 +01:00
test_fortify.sh fortify: Update compile-time tests for Clang 14 2022-02-13 16:50:06 -08:00
tools-support-relr.sh Makefile: use -z pack-relative-relocs 2023-04-17 11:23:06 +09:00
unifdef.c
ver_linux Removed the oprofiled version option 2021-05-03 17:23:06 -06:00
xen-hypercalls.sh scripts: make some scripts executable 2021-08-10 09:13:25 +09:00
xz_wrap.sh scripts: clean up IA-64 code 2023-12-03 18:51:48 +09:00