Changes in Makefile.modfinal

1b466b29 - kbuild: re-enable KCSAN for autogenerated *.mod.c intermediaries

Wed, 13 Nov 2024 23:45:23 +0000

kbuild: re-enable KCSAN for autogenerated *.mod.c intermediariesThis reverts commit 54babdc0343f ("kbuild: Disable KCSAN forautogenerated *.mod.c intermediaries").Now that objtool is enabled for *.mod.c, there is no need to filterout CFLAGS_KCSAN.I no longer see "Unpatched return thunk in use. This should not happen!"error with KCSAN when loading a module.Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/Makefile.modfinal

bede1696 - kbuild: enable objtool for *.mod.o and additional kernel objects

Wed, 13 Nov 2024 23:45:22 +0000

kbuild: enable objtool for *.mod.o and additional kernel objectsCurrently, objtool is disabled in scripts/Makefile.{modfinal,vmlinux}.This commit moves rule_cc_o_c and rule_as_o_S to scripts/Makefile.liband set objtool-enabled to y there.With this change, *.mod.o, .module-common.o, builtin-dtb.o, andvmlinux.export.o will now be covered by objtool.Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/Makefile.modfinal

000e22a8 - kbuild: move cmd_cc_o_c and cmd_as_o_S to scripts/Malefile.lib

Wed, 13 Nov 2024 23:45:21 +0000

kbuild: move cmd_cc_o_c and cmd_as_o_S to scripts/Malefile.libThe cmd_cc_o_c and cmd_as_o_S macros are duplicated inscripts/Makefile.{build,modfinal,vmlinux}.This commit factors them out to scripts/Makefile.lib.No functional changes are intended.Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/Makefile.modfinal

bad6beb2 - kbuild: remove extmod_prefix, MODORDER, MODULES_NSDEPS variables

Sun, 10 Nov 2024 01:34:34 +0000

kbuild: remove extmod_prefix, MODORDER, MODULES_NSDEPS variablesWith the previous changes, $(extmod_prefix), $(MODORDER), and$(MODULES_NSDEPS) are constant. (empty, modules.order, andmodules.nsdeps, respectively).Remove these variables and hard-code their values.Signed-off-by: Masahiro Yamada Reviewed-by: Nicolas Schier List of files: /linux-6.15/scripts/Makefile.modfinal

214c0eea - kbuild: add $(objtree)/ prefix to some in-kernel build artifacts

Sun, 10 Nov 2024 01:34:30 +0000

kbuild: add $(objtree)/ prefix to some in-kernel build artifacts$(objtree) refers to the top of the output directory of kernel builds.This commit adds the explicit $(objtree)/ prefix to build artifactsneeded for building external modules.This change has no immediate impact, as the top-level Makefilecurrently defines: objtree := .This commit prepares for supporting the building of external modulesin a different directory.Signed-off-by: Masahiro Yamada Reviewed-by: Nicolas Schier List of files: /linux-6.15/scripts/Makefile.modfinal

cc6d281f - kbuild: remove append operation on cmd_ld_ko_o

Sun, 08 Sep 2024 13:26:00 +0000

kbuild: remove append operation on cmd_ld_ko_oThe append operation was introduced incommit b1a1a1a09b46 ("kbuild: lto: postpone objtool")when the command was created from two parts.In commit 850ded46c642 ("kbuild: Fix TRIM_UNUSED_KSYMS with LTO_CLANG")however the first part was removed again, making the append operationunnecessary.To keep this command definition aligned with all other commanddefinitions, remove the append again.Signed-off-by: Thomas Weißschuh Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/Makefile.modfinal

fdf94e44 - kbuild: compile constant module information only once

Sun, 01 Sep 2024 17:55:21 +0000

kbuild: compile constant module information only onceVarious information about modules is compiled into the info sections.For that a dedicated .mod.c file is generated by modpost for each moduleand then linked into the module.However most of the information in the .mod.c is the same for allmodules, internal and external.Split the shared information into a dedicated source file that iscompiled once and then linked into all modules.This avoids frequent rebuilds for all .mod.c files when usingCONFIG_LOCALVERSION_AUTO because the local version ends up in .mod.cthrough UTS_RELEASE and VERMAGIC_STRING.The modules are still relinked in this case.The code is also easier to maintain as it's now in a proper source fileinstead of an inline string literal.Signed-off-by: Thomas Weißschuh Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/Makefile.modfinal

8fb4ac1c - kbuild: fix typos "prequisites" to "prerequisites"

Sun, 18 Aug 2024 07:07:11 +0000

kbuild: fix typos "prequisites" to "prerequisites"This typo in scripts/Makefile.build has been present for more than 20years. It was accidentally copy-pasted to other scripts/Makefile.* files.Fix them all.Signed-off-by: Masahiro Yamada Reviewed-by: Nathan Chancellor List of files: /linux-6.15/scripts/Makefile.modfinal

46fb0b62 - kbuild,bpf: Add module-specific pahole flags for distilled base BTF

Thu, 20 Jun 2024 09:17:32 +0000

kbuild,bpf: Add module-specific pahole flags for distilled base BTFSupport creation of module BTF along with distilled base BTF;the latter is stored in a .BTF.base ELF section and supplementssplit BTF references to base BTF with information about base types,allowing for later relocation of split BTF with a (possiblychanged) base. resolve_btfids detects the presence of a .BTF.basesection and will use it instead of the base BTF it is passed inBTF id resolution.Modules will be built with a distilled .BTF.base section for externalmodule build, i.e.make -C. -M=path2/module...while in-tree module build as part of a normal kernel build willnot generate distilled base BTF; this is because in-tree moduleschange with the kernel and do not require BTF relocation for therunning vmlinux.Signed-off-by: Alan Maguire Signed-off-by: Andrii Nakryiko Reviewed-by: Eduard Zingerman Link: https://lore.kernel.org/bpf/20240620091733.1967885-6-alan.maguire@oracle.com List of files: /linux-6.15/scripts/Makefile.modfinal

b4f944ba - kbuild: use GCOV_PROFILE and KCSAN_SANITIZE in scripts/Makefile.modfinal

Mon, 06 May 2024 13:35:44 +0000

kbuild: use GCOV_PROFILE and KCSAN_SANITIZE in scripts/Makefile.modfinalInstead of filtering out the GCOV and KCSAN flags, let's set GCOV_PROFILEand KCSAN_SANITIZE to 'n', as in other Makefiles.Signed-off-by: Masahiro Yamada Reviewed-by: Kees Cook Tested-by: Roberto Sassu List of files: /linux-6.15/scripts/Makefile.modfinal

54babdc0 - kbuild: Disable KCSAN for autogenerated *.mod.c intermediaries

Tue, 26 Mar 2024 20:25:48 +0000

kbuild: Disable KCSAN for autogenerated *.mod.c intermediariesWhen KCSAN and CONSTRUCTORS are enabled, one can trigger the "Unpatched return thunk in use. This should not happen!"catch-all warning.Usually, when objtool runs on the .o objects, it does generate a section.return_sites which contains all offsets in the objects to the returnthunks of the functions present there. Those return thunks then getpatched at runtime by the alternatives.KCSAN and CONSTRUCTORS add this to the object file's .text.startupsection: ------------------- Disassembly of section .text.startup: ... 0000000000000010 <_sub_I_00099_0>: 10: f3 0f 1e fa endbr64 14: e8 00 00 00 00 call 19 <_sub_I_00099_0+0x9> 15: R_X86_64_PLT32 __tsan_init-0x4 19: e9 00 00 00 00 jmp 1e <__UNIQUE_ID___addressable_cryptd_alloc_aead349+0x6> 1a: R_X86_64_PLT32 __x86_return_thunk-0x4 -------------------which, if it is built as a module goes through the intermediary stage ofcreating a .mod.c file which, when translated, receives a secondconstructor: ------------------- Disassembly of section .text.startup: 0000000000000010 <_sub_I_00099_0>: 10: f3 0f 1e fa endbr64 14: e8 00 00 00 00 call 19 <_sub_I_00099_0+0x9> 15: R_X86_64_PLT32 __tsan_init-0x4 19: e9 00 00 00 00 jmp 1e <_sub_I_00099_0+0xe> 1a: R_X86_64_PLT32 __x86_return_thunk-0x4 ... 0000000000000030 <_sub_I_00099_0>: 30: f3 0f 1e fa endbr64 34: e8 00 00 00 00 call 39 <_sub_I_00099_0+0x9> 35: R_X86_64_PLT32 __tsan_init-0x4 39: e9 00 00 00 00 jmp 3e <__ksymtab_cryptd_alloc_ahash+0x2> 3a: R_X86_64_PLT32 __x86_return_thunk-0x4 -------------------in the .ko file.Objtool has run already so that second constructor's return thunk cannotbe added to the .return_sites section and thus the return thunk remainsunpatched and the warning rightfully fires.Drop KCSAN flags from the mod.c generation stage as those constructorsdo not contain data races one would be interested about.Debugged together with David Kaplan and NikolayBorisov .Reported-by: Paul Menzel Closes: https://lore.kernel.org/r/0851a207-7143-417e-be31-8bf2b3afb57d@molgen.mpg.deSigned-off-by: Borislav Petkov (AMD) Tested-by: Paul Menzel # Dell XPS 13Reviewed-by: Nikolay Borisov Reviewed-by: Marco Elver Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/Makefile.modfinal

7f6d8f7e - kbuild: remove ARCH_POSTLINK from module builds

Wed, 18 Oct 2023 15:19:47 +0000

kbuild: remove ARCH_POSTLINK from module buildsThe '%.ko' rule in arch/*/Makefile.postlink does nothing but call the'true' command.Remove the unneeded code.Signed-off-by: Masahiro Yamada Reviewed-by: Nicolas Schier List of files: /linux-6.15/scripts/Makefile.modfinal

41bdc6de - btf, scripts: rust: drop is_rust_module.sh

Tue, 04 Jul 2023 05:21:36 +0000

btf, scripts: rust: drop is_rust_module.shWith commit c1177979af9c ("btf, scripts: Exclude Rust CUs with pahole")we are now able to use pahole directly to identify Rust compilationunits (CUs) and exclude them from generating BTF debugging information(when DEBUG_INFO_BTF is enabled).And if pahole doesn't support the --lang-exclude flag, we can't enableboth RUST and DEBUG_INFO_BTF at the same time.So, in any case, the script is_rust_module.sh is just redundant and wecan drop it.NOTE: we may also be able to drop the "Rust loadable module" markinside Rust modules, but it seems safer to keep it for now to make surewe are not breaking any external tool that may potentially rely on it.Signed-off-by: Andrea Righi Reviewed-by: Nathan Chancellor Tested-by: Eric Curtin Reviewed-by: Eric Curtin Reviewed-by: Neal Gompa Reviewed-by: Masahiro Yamada Reviewed-by: Martin Rodriguez Reboredo Acked-by: Daniel Xu Link: https://lore.kernel.org/r/20230704052136.155445-1-andrea.righi@canonical.com[ Picked the `Reviewed-by`s from the old patch too. ]Signed-off-by: Miguel Ojeda List of files: /linux-6.15/scripts/Makefile.modfinal

25a21fbb - kbuild: Disable GCOV for *.mod.o

Fri, 23 Jun 2023 00:11:43 +0000

kbuild: Disable GCOV for *.mod.oWith GCOV_PROFILE_ALL, Clang injects __llvm_gcov_* functions to eachobject file, including the *.mod.o. As we filter out CC_FLAGS_CFIfor *.mod.o, the compiler won't generate type hashes for theinjected functions, and therefore indirectly calling them duringmodule loading trips indirect call checking.Enabling CFI for *.mod.o isn't sufficient to fix this issue aftercommit 0c3e806ec0f9 ("x86/cfi: Add boot time hash randomization"),as *.mod.o aren't processed by objtool, which means any hashesemitted there won't be randomized. Therefore, in addition todisabling CFI for *.mod.o, also disable GCOV, as the object filesdon't otherwise contain any executable code.Fixes: cf68fffb66d6 ("add support for Clang CFI")Reported-by: Joe Fradley Signed-off-by: Sami Tolvanen Acked-by: Peter Zijlstra (Intel) Reviewed-by: Kees Cook Reviewed-by: Nick Desaulniers Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/Makefile.modfinal

92215e7a - kbuild: rename cmd_$@ to savedcmd_$@ in *.cmd files

Thu, 29 Dec 2022 09:15:00 +0000

kbuild: rename cmd_$@ to savedcmd_$@ in *.cmd filesThe cmd-check macro compares $(cmd_$@) and $(cmd_$1), but a pitfall isthat you cannot use cmd_ as the variable name for the command.For example, the following code will not work in the top Makefileor ./Kbuild. quiet_cmd_foo = GEN $@ cmd_foo = touch $@ targets += foo foo: FORCE $(call if_changed,foo)In this case, both $@ and $1 are expanded to 'foo', so $(cmd_check)is always empty.We do not need to use the same prefix for cmd_$@ and cmd_$1.Rename the former to savedcmd_$@.Signed-off-by: Masahiro Yamada Reviewed-by: Nicolas Schier List of files: /linux-6.15/scripts/Makefile.modfinal

f65a4868 - kbuild: change module.order to list .o instead of .ko

Sun, 11 Dec 2022 13:04:07 +0000

kbuild: change module.order to list *.o instead of *.koscripts/Makefile.build replaces the suffix .o with .ko, thenscripts/Makefile.modpost calls the sed command to change .ko backto the original .o suffix.Instead of converting the suffixes back-and-forth, store the .o pathsin modules.order, and replace it with .ko in 'make modules_install'.This avoids the unneeded sed command.Signed-off-by: Masahiro Yamada Reviewed-by: Luis Chamberlain List of files: /linux-6.15/scripts/Makefile.modfinal

6768fa4b - kbuild: add read-file macro

Sun, 11 Dec 2022 02:54:47 +0000

kbuild: add read-file macroSince GNU Make 4.2, $(file ...) supports the read operater '<', whichis useful to read a file without forking a new process. No warning isshown even if the input file is missing.For older Make versions, it falls back to the cat command.Signed-off-by: Masahiro Yamada Reviewed-by: Nicolas Schier Reviewed-by: Alexander Lobakin Tested-by: Alexander Lobakin List of files: /linux-6.15/scripts/Makefile.modfinal

a5db80c6 - kbuild: do not sort after reading modules.order

Sun, 11 Dec 2022 09:49:18 +0000

kbuild: do not sort after reading modules.ordermodules.order lists modules in the deterministic order (that is why"modules order"), and there is no duplication in the list.$(sort ) is pointless.Signed-off-by: Masahiro Yamada Reviewed-by: Nicolas Schier List of files: /linux-6.15/scripts/Makefile.modfinal

f73edc89 - kbuild: unify two modpost invocations

Sat, 24 Sep 2022 18:19:13 +0000

kbuild: unify two modpost invocationsCurrently, modpost is executed twice; first for vmlinux, secondfor modules.This commit merges them.Current build flow================== 1) build obj-y and obj-m objects 2) link vmlinux.o 3) modpost for vmlinux 4) link vmlinux 5) modpost for modules 6) link modules (*.ko)The build steps 1) through 6) are serialized, that is, modules arebuilt after vmlinux. You do not get benefits of parallel builds whenscripts/link-vmlinux.sh is being run.New build flow============== 1) build obj-y and obj-m objects 2) link vmlinux.o 3) modpost for vmlinux and modules 4a) link vmlinux 4b) link modules (*.ko)In the new build flow, modpost is invoked just once.vmlinux and modules are built in parallel. One exception isCONFIG_DEBUG_INFO_BTF_MODULES=y, where modules depend on vmlinux.Signed-off-by: Masahiro Yamada Tested-by: Nick Desaulniers Reviewed-by: Nicolas Schier List of files: /linux-6.15/scripts/Makefile.modfinal

2f7ab126 - Kbuild: add Rust support

Sat, 03 Jul 2021 14:42:57 +0000

Kbuild: add Rust supportHaving most of the new files in place, we now enable Rust supportin the build system, including `Kconfig` entries related to Rust,the Rust configuration printer and a few other bits.Reviewed-by: Kees Cook Reviewed-by: Nick Desaulniers Tested-by: Nick Desaulniers Reviewed-by: Greg Kroah-Hartman Co-developed-by: Alex Gaynor Signed-off-by: Alex Gaynor Co-developed-by: Finn Behrens Signed-off-by: Finn Behrens Co-developed-by: Adam Bratschi-Kaye Signed-off-by: Adam Bratschi-Kaye Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Co-developed-by: Michael Ellerman Signed-off-by: Michael Ellerman Co-developed-by: Sven Van Asbroeck Signed-off-by: Sven Van Asbroeck Co-developed-by: Gary Guo Signed-off-by: Gary Guo Co-developed-by: Boris-Chengbiao Zhou Signed-off-by: Boris-Chengbiao Zhou Co-developed-by: Boqun Feng Signed-off-by: Boqun Feng Co-developed-by: Douglas Su Signed-off-by: Douglas Su Co-developed-by: Dariusz Sosnowski Signed-off-by: Dariusz Sosnowski Co-developed-by: Antonio Terceiro Signed-off-by: Antonio Terceiro Co-developed-by: Daniel Xu Signed-off-by: Daniel Xu Co-developed-by: Björn Roy Baron Signed-off-by: Björn Roy Baron Co-developed-by: Martin Rodriguez Reboredo Signed-off-by: Martin Rodriguez Reboredo Signed-off-by: Miguel Ojeda List of files: /linux-6.15/scripts/Makefile.modfinal