Changes in Makefile.vmlinux

e0cd396d - kbuild: fix typos "module.builtin" to "modules.builtin"

Mon, 12 May 2025 05:36:58 +0000

kbuild: fix typos "module.builtin" to "modules.builtin"The filenames in the comments do not match the actual generated files.Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/Makefile.vmlinux

f0e4b333 - kbuild: fix dependency on sorttable

Sun, 11 May 2025 03:55:19 +0000

kbuild: fix dependency on sorttableCommit ac4f06789b4f ("kbuild: Create intermediate vmlinux build withrelocations preserved") missed replacing one occurrence of "vmlinux"that was added during the same development cycle.Fixes: ac4f06789b4f ("kbuild: Create intermediate vmlinux build with relocations preserved")Signed-off-by: Masahiro Yamada Acked-by: Ard Biesheuvel List of files: /linux-6.15/scripts/Makefile.vmlinux

e9d86b8e - scripts: Do not strip .rela.dyn section

Tue, 08 Apr 2025 07:28:51 +0000

scripts: Do not strip .rela.dyn sectionThe .rela.dyn section contains runtime relocations and is only emittedfor a relocatable kernel.riscv uses this section to relocate the kernel at runtime but that sectionis stripped from vmlinux. That prevents kexec to successfully load vmlinuxsince it does not contain the relocations info needed.Fixes: 559d1e45a16d ("riscv: Use --emit-relocs in order to move .rela.dyn in init")Tested-by: Björn Töpel Reviewed-by: Björn Töpel Acked-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20250408072851.90275-1-alexghiti@rivosinc.comSigned-off-by: Alexandre Ghiti List of files: /linux-6.15/scripts/Makefile.vmlinux

ac4f0678 - kbuild: Create intermediate vmlinux build with relocations preserved

Tue, 11 Mar 2025 11:06:20 +0000

kbuild: Create intermediate vmlinux build with relocations preservedThe imperative paradigm used to build vmlinux, extract some info from itor perform some checks on it, and subsequently modify it again goesagainst the declarative paradigm that is usually employed for definingmake rules.In particular, the Makefile.postlink files that consume their input viaan output rule result in some dodgy logic in the decompressor makefilesfor RISC-V and x86, given that the vmlinux.relocs input file needed togenerate the arch-specific relocation tables may not exist or be out ofdate, but cannot be constructed using the ordinary Make dependency basedrules, because the info needs to be extracted while vmlinux is in itsephemeral, non-stripped form.So instead, for architectures that require the static relocations thatare emitted into vmlinux when passing --emit-relocs to the linker, andare subsequently stripped out again, introduce an intermediate vmlinuxtarget called vmlinux.unstripped, and organize the reset of the buildlogic accordingly:- vmlinux.unstripped is created only once, and not updated again- build rules under arch/*/boot can depend on vmlinux.unstripped without running the risk of the data disappearing or being out of date- the final vmlinux generated by the build is not bloated with static relocations that are never needed again after the build completes.Signed-off-by: Ard Biesheuvel Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/Makefile.vmlinux

e22bbb8e - kbuild: link-vmlinux.sh: Make output file name configurable

Tue, 11 Mar 2025 11:06:18 +0000

kbuild: link-vmlinux.sh: Make output file name configurableIn order to introduce an intermediate, non-stripped vmlinux build thatcan be used by other build steps as an input, pass the output file nameto link-vmlinux.sh via its command line.Signed-off-by: Ard Biesheuvel Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/Makefile.vmlinux

82c09de2 - kbuild: add dependency from vmlinux to sorttable

Wed, 26 Feb 2025 13:30:14 +0000

kbuild: add dependency from vmlinux to sorttableWithout this dependency it's really puzzling when we bisect for a "bad"commit in a series of sorttable change: when "git bisect" switches toanother commit, "make" just does nothing to vmlinux.Signed-off-by: Xi Ruoyao Acked-by: Steven Rostedt (Google) Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/Makefile.vmlinux

18e9944e - kbuild: add dependency from vmlinux to resolve_btfids

Sat, 23 Nov 2024 13:33:37 +0000

kbuild: add dependency from vmlinux to resolve_btfidsresolve_btfids is used by link-vmlinux.sh.In contrast to other configuration options and targets no transitivedependency between resolve_btfids and vmlinux.Add an explicit one.Signed-off-by: Thomas Weißschuh Acked-by: Jiri Olsa Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/Makefile.vmlinux

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.vmlinux

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.vmlinux

654102df - kbuild: add generic support for built-in boot DTBs

Mon, 23 Sep 2024 07:56:03 +0000

kbuild: add generic support for built-in boot DTBsSome architectures embed boot DTBs in vmlinux. A potential issue forthese architectures is a race condition during parallel builds becauseKbuild descends into arch/*/boot/dts/ twice.One build thread is initiated by the 'dtbs' target, which is aprerequisite of the 'all' target in the top-level Makefile: ifdef CONFIG_OF_EARLY_FLATTREE all: dtbs endifFor architectures that support the built-in boot dtb, arch/*/boot/dts/is visited also during the ordinary directory traversal in order tobuild obj-y objects that wrap DTBs.Since these build threads are unaware of each other, they can runsimultaneously during parallel builds.This commit introduces a generic build rule to scripts/Makefile.vmlinuxto support embedded boot DTBs in a race-free way. Architectures thatwant to use this rule need to select CONFIG_GENERIC_BUILTIN_DTB.After the migration, Makefiles under arch/*/boot/dts/ will be visitedonly once to build only *.dtb files.This change also aims to unify the CONFIG options used for built-in DTBssupport. Currently, different architectures use different CONFIG optionsfor the same purposes.With this commit, the CONFIG options will be unified as follows: - CONFIG_GENERIC_BUILTIN_DTB This enables the generic rule for built-in boot DTBs. This will be renamed to CONFIG_BUILTIN_DTB after all architectures migrate to the generic rule. - CONFIG_BUILTIN_DTB_NAME This specifies the path to the embedded DTB. (relative to arch/*/boot/dts/) - CONFIG_BUILTIN_DTB_ALL If this is enabled, all DTB files compiled under arch/*/boot/dts/ are embedded into vmlinux. Only used by MIPS.Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/Makefile.vmlinux

1198c9c6 - kbuild: Add generic hook for architectures to use before the final vmlinux link

Wed, 30 Oct 2024 07:08:44 +0000

kbuild: Add generic hook for architectures to use before the final vmlinux linkOn powerpc, we would like to be able to make a pass on vmlinux.o andgenerate a new object file to be linked into vmlinux. Add a generic passin Makefile.vmlinux that architectures can use for this purpose.Architectures need to select CONFIG_ARCH_WANTS_PRE_LINK_VMLINUX and mustprovide arch//tools/Makefile with .arch.vmlinux.o target, whichwill be invoked prior to the final vmlinux link step.Acked-by: Masahiro Yamada Signed-off-by: Naveen N Rao Signed-off-by: Hari Bathini Signed-off-by: Michael Ellerman Link: https://patch.msgid.link/20241030070850.1361304-12-hbathini@linux.ibm.com List of files: /linux-6.15/scripts/Makefile.vmlinux

5f5e7344 - kbuild: generate offset range data for builtin modules

Fri, 06 Sep 2024 14:45:03 +0000

kbuild: generate offset range data for builtin modulesCreate file module.builtin.ranges that can be used to find wherebuilt-in modules are located by their addresses. This will be useful fortracing tools to find what functions are for various built-in modules.The offset range data for builtin modules is generated using: - modules.builtin: associates object files with module names - vmlinux.map: provides load order of sections and offset of first member per section - vmlinux.o.map: provides offset of object file content per section - .*.cmd: build cmd file with KBUILD_MODFILEThe generated data will look like:.text 00000000-00000000 = _text.text 0000baf0-0000cb10 amd_uncore.text 0009bd10-0009c8e0 iosf_mbi....text 00b9f080-00ba011a intel_skl_int3472_discrete.text 00ba0120-00ba03c0 intel_skl_int3472_discrete intel_skl_int3472_tps68470.text 00ba03c0-00ba08d6 intel_skl_int3472_tps68470....data 00000000-00000000 = _sdata.data 0000f020-0000f680 amd_uncoreFor each ELF section, it lists the offset of the first symbol. This canbe used to determine the base address of the section at runtime.Next, it lists (in strict ascending order) offset ranges in that sectionthat cover the symbols of one or more builtin modules. Multiple rangescan apply to a single module, and ranges can be shared between modules.The CONFIG_BUILTIN_MODULE_RANGES option controls whether offset range datais generated for kernel modules that are built into the kernel image.How it works: 1. The modules.builtin file is parsed to obtain a list of built-in module names and their associated object names (the .ko file that the module would be in if it were a loadable module, hereafter referred to as ). This object name can be used to identify objects in the kernel compile because any C or assembler code that ends up into a built-in module will have the option -DKBUILD_MODFILE= present in its build command, and those can be found in the ..cmd file in the kernel build tree. If an object is part of multiple modules, they will all be listed in the KBUILD_MODFILE option argument. This allows us to conclusively determine whether an object in the kernel build belong to any modules, and which. 2. The vmlinux.map is parsed next to determine the base address of each top level section so that all addresses into the section can be turned into offsets. This makes it possible to handle sections getting loaded at different addresses at system boot. We also determine an 'anchor' symbol at the beginning of each section to make it possible to calculate the true base address of a section at runtime (i.e. symbol address - symbol offset). We collect start addresses of sections that are included in the top level section. This is used when vmlinux is linked using vmlinux.o, because in that case, we need to look at the vmlinux.o linker map to know what object a symbol is found in. And finally, we process each symbol that is listed in vmlinux.map (or vmlinux.o.map) based on the following structure: vmlinux linked from vmlinux.a: vmlinux.map: -- might be same as top level section) -- built-in association known -- belongs to module(s) object belongs to ... vmlinux linked from vmlinux.o: vmlinux.map: -- might be same as top level section) vmlinux.o -- need to use vmlinux.o.map -- ignored ... vmlinux.o.map:

-- built-in association known -- belongs to module(s) object belongs to ... 3. As sections, objects, and symbols are processed, offset ranges are constructed in a straight-forward way: - If the symbol belongs to one or more built-in modules: - If we were working on the same module(s), extend the range to include this object - If we were working on another module(s), close that range, and start the new one - If the symbol does not belong to any built-in modules: - If we were working on a module(s) range, close that rangeSigned-off-by: Kris Van Hees Reviewed-by: Nick Alcock Reviewed-by: Alan Maguire Reviewed-by: Steven Rostedt (Google) Tested-by: Sam James Reviewed-by: Sami Tolvanen Tested-by: Sami Tolvanen Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/Makefile.vmlinux

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.vmlinux

7f7f6f7a - Makefile: remove redundant tool coverage variables

Mon, 06 May 2024 13:35:43 +0000

Makefile: remove redundant tool coverage variablesNow Kbuild provides reasonable defaults for objtool, sanitizers, andprofilers.Remove redundant variables.Note:This commit changes the coverage for some objects: - include arch/mips/vdso/vdso-image.o into UBSAN, GCOV, KCOV - include arch/sparc/vdso/vdso-image-*.o into UBSAN - include arch/sparc/vdso/vma.o into UBSAN - include arch/x86/entry/vdso/extable.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vdso-image-*.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vdso32-setup.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vma.o into GCOV, KCOV - include arch/x86/um/vdso/vma.o into KASAN, GCOV, KCOVI believe these are positive effects because all of them are kernelspace objects.Signed-off-by: Masahiro Yamada Reviewed-by: Kees Cook Tested-by: Roberto Sassu List of files: /linux-6.15/scripts/Makefile.vmlinux

2d7ce49f - x86/retpoline: Make sure there are no unconverted return thunks due to KCSAN

Tue, 17 Oct 2023 16:59:46 +0000

x86/retpoline: Make sure there are no unconverted return thunks due to KCSANEnabling CONFIG_KCSAN leads to unconverted, default return thunks toremain after patching.As David Kaplan describes in his debugging of the issue, it is caused bya couple of KCSAN-generated constructors which aren't processed byobjtool: "When KCSAN is enabled, GCC generates lots of constructor functions named _sub_I_00099_0 which call __tsan_init and then return. The returns in these are generally annotated normally by objtool and fixed up at runtime. But objtool runs on vmlinux.o and vmlinux.o does not include a couple of object files that are in vmlinux, like init/version-timestamp.o and .vmlinux.export.o, both of which contain _sub_I_00099_0 functions. As a result, the returns in these functions are not annotated, and the panic occurs when we call one of them in do_ctors and it uses the default return thunk. This difference can be seen by counting the number of these functions in the object files: $ objdump -d vmlinux.o|grep -c "<_sub_I_00099_0>:" 2601 $ objdump -d vmlinux|grep -c "<_sub_I_00099_0>:" 2603 If these functions are only run during kernel boot, there is no speculation concern."Fix it by disabling KCSAN on version-timestamp.o and .vmlinux.export.oso the extra functions don't get generated. KASAN and GCOV are alreadydisabled for those files. [ bp: Massage commit message. ]Closes: https://lore.kernel.org/lkml/20231016214810.GA3942238@dev-arch.thelio-3990X/Reported-by: Nathan Chancellor Signed-off-by: Josh Poimboeuf Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Nick Desaulniers Acked-by: Marco Elver Tested-by: Nathan Chancellor Link: https://lore.kernel.org/r/20231017165946.v4i2d4exyqwqq3bx@treble List of files: /linux-6.15/scripts/Makefile.vmlinux

ddf56288 - kbuild: Fix CFI failures with GCOV

Fri, 23 Jun 2023 00:11:42 +0000

kbuild: Fix CFI failures with GCOVWith GCOV_PROFILE_ALL, Clang injects __llvm_gcov_* functions toeach object file, and the functions are indirectly called duringboot. However, when code is injected to object files that are notpart of vmlinux.o, it's also not processed by objtool, which breaksCFI hash randomization as the hashes in these files won't beincluded in the .cfi_sites section and thus won't be randomized.Similarly to commit 42633ed852de ("kbuild: Fix CFI hashrandomization with KASAN"), disable GCOV for .vmlinux.export.o andinit/version-timestamp.o to avoid emitting unnecessary functions toobject files that don't otherwise have executable code.Fixes: 0c3e806ec0f9 ("x86/cfi: Add boot time hash randomization")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.vmlinux

42633ed8 - kbuild: Fix CFI hash randomization with KASAN

Thu, 12 Jan 2023 22:49:48 +0000

kbuild: Fix CFI hash randomization with KASANClang emits a asan.module_ctor constructor to each object filewhen KASAN is enabled, and these functions are indirectly calledin do_ctors. With CONFIG_CFI_CLANG, the compiler also emits a CFItype hash before each address-taken global function so they canpass indirect call checks.However, in commit 0c3e806ec0f9 ("x86/cfi: Add boot time hashrandomization"), x86 implemented boot time hash randomization,which relies on the .cfi_sites section generated by objtool. Asobjtool is run against vmlinux.o instead of individual objectfiles with X86_KERNEL_IBT (enabled by default), CFI types inobject files that are not part of vmlinux.o end up not beingincluded in .cfi_sites, and thus won't get randomized and tripCFI when called.Only .vmlinux.export.o and init/version-timestamp.o are linkedinto vmlinux separately from vmlinux.o. As these files don'tcontain any functions, disable KASAN for both of them to avoidbreaking hash randomization.Link: https://github.com/ClangBuiltLinux/linux/issues/1742Fixes: 0c3e806ec0f9 ("x86/cfi: Add boot time hash randomization")Signed-off-by: Sami Tolvanen Acked-by: Peter Zijlstra (Intel) Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20230112224948.1479453-2-samitolvanen@google.com List of files: /linux-6.15/scripts/Makefile.vmlinux

5d4aeffb - kbuild: rebuild .vmlinux.export.o when its prerequisite is updated

Wed, 28 Sep 2022 06:39:41 +0000

kbuild: rebuild .vmlinux.export.o when its prerequisite is updatedWhen include/linux/export-internal.h is updated, .vmlinux.export.omust be rebuilt, but it does not happen because its rule is hiddenbehind scripts/link-vmlinux.sh.Move it out of the shell script, so that Make can see the dependencybetween vmlinux and .vmlinux.export.o.Move the vmlinux rule to scripts/Makefile.vmlinux.Signed-off-by: Masahiro Yamada List of files: /linux-6.15/scripts/Makefile.vmlinux

7b453719 - kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS

Fri, 13 May 2022 11:39:22 +0000

kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCSinclude/{linux,asm-generic}/export.h defines a weak symbol, __crc_*as a placeholder.Genksyms writes the version CRCs into the linker script, which will beused for filling the __crc_* symbols. The linker script format dependson CONFIG_MODULE_REL_CRCS. If it is enabled, __crc_* holds the offsetto the reference of CRC.It is time to get rid of this complexity.Now that modpost parses text files (.*.cmd) to collect all the CRCs,it can generate C code that will be linked to the vmlinux or modules.Generate a new C file, .vmlinux.export.c, which contains the CRCs ofsymbols exported by vmlinux. It is compiled and linked to vmlinux inscripts/link-vmlinux.sh.Put the CRCs of symbols exported by modules into the existing *.mod.cfiles. No additional build step is needed for modules. As before,*.mod.c are compiled and linked to *.ko in scripts/Makefile.modfinal.No linker magic is used here. The new C implementation works in thesame way, whether CONFIG_RELOCATABLE is enabled or not.CONFIG_MODULE_REL_CRCS is no longer needed.Previously, Kbuild invoked additional $(LD) to update the CRCs inobjects, but this step is unneeded too.Signed-off-by: Masahiro Yamada Tested-by: Nathan Chancellor Tested-by: Nicolas Schier Reviewed-by: Nicolas Schier Tested-by: Sedat Dilek # LLVM-14 (x86-64) List of files: /linux-6.15/scripts/Makefile.vmlinux