From 7f7f6f7ad654b326897c9f54438a06f03454bd0d Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 6 May 2024 22:35:43 +0900 Subject: Makefile: remove redundant tool coverage variables Now Kbuild provides reasonable defaults for objtool, sanitizers, and profilers. 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, KCOV I believe these are positive effects because all of them are kernel space objects. Signed-off-by: Masahiro Yamada Reviewed-by: Kees Cook Tested-by: Roberto Sassu --- scripts/Makefile.vmlinux | 3 --- 1 file changed, 3 deletions(-) (limited to 'scripts/Makefile.vmlinux') diff --git a/scripts/Makefile.vmlinux b/scripts/Makefile.vmlinux index c9f3e03124d7..49946cb96844 100644 --- a/scripts/Makefile.vmlinux +++ b/scripts/Makefile.vmlinux @@ -18,9 +18,6 @@ quiet_cmd_cc_o_c = CC $@ $(call if_changed_dep,cc_o_c) ifdef CONFIG_MODULES -KASAN_SANITIZE_.vmlinux.export.o := n -KCSAN_SANITIZE_.vmlinux.export.o := n -GCOV_PROFILE_.vmlinux.export.o := n targets += .vmlinux.export.o vmlinux: .vmlinux.export.o endif -- cgit v1.2.3 From 8fb4ac1cee88a57e7a56faba49b408a41a4af4db Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 18 Aug 2024 16:07:11 +0900 Subject: kbuild: fix typos "prequisites" to "prerequisites" This typo in scripts/Makefile.build has been present for more than 20 years. It was accidentally copy-pasted to other scripts/Makefile.* files. Fix them all. Signed-off-by: Masahiro Yamada Reviewed-by: Nathan Chancellor --- scripts/Makefile.vmlinux | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/Makefile.vmlinux') diff --git a/scripts/Makefile.vmlinux b/scripts/Makefile.vmlinux index 49946cb96844..5ceecbed31eb 100644 --- a/scripts/Makefile.vmlinux +++ b/scripts/Makefile.vmlinux @@ -33,7 +33,7 @@ targets += vmlinux vmlinux: scripts/link-vmlinux.sh vmlinux.o $(KBUILD_LDS) FORCE +$(call if_changed_dep,link_vmlinux) -# Add FORCE to the prequisites of a target to force it to be always rebuilt. +# Add FORCE to the prerequisites of a target to force it to be always rebuilt. # --------------------------------------------------------------------------- PHONY += FORCE -- cgit v1.2.3 From 5f5e7344322f0b0676579af054c787ed57d1c1df Mon Sep 17 00:00:00 2001 From: Kris Van Hees Date: Fri, 6 Sep 2024 10:45:03 -0400 Subject: kbuild: generate offset range data for builtin modules Create file module.builtin.ranges that can be used to find where built-in modules are located by their addresses. This will be useful for tracing 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_MODFILE The 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_uncore For each ELF section, it lists the offset of the first symbol. This can be used to determine the base address of the section at runtime. Next, it lists (in strict ascending order) offset ranges in that section that cover the symbols of one or more builtin modules. Multiple ranges can apply to a single module, and ranges can be shared between modules. The CONFIG_BUILTIN_MODULE_RANGES option controls whether offset range data is 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 range Signed-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 --- scripts/Makefile.vmlinux | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'scripts/Makefile.vmlinux') diff --git a/scripts/Makefile.vmlinux b/scripts/Makefile.vmlinux index 5ceecbed31eb..1284f05555b9 100644 --- a/scripts/Makefile.vmlinux +++ b/scripts/Makefile.vmlinux @@ -33,6 +33,24 @@ targets += vmlinux vmlinux: scripts/link-vmlinux.sh vmlinux.o $(KBUILD_LDS) FORCE +$(call if_changed_dep,link_vmlinux) +# module.builtin.ranges +# --------------------------------------------------------------------------- +ifdef CONFIG_BUILTIN_MODULE_RANGES +__default: modules.builtin.ranges + +quiet_cmd_modules_builtin_ranges = GEN $@ + cmd_modules_builtin_ranges = gawk -f $(real-prereqs) > $@ + +targets += modules.builtin.ranges +modules.builtin.ranges: $(srctree)/scripts/generate_builtin_ranges.awk \ + modules.builtin vmlinux.map vmlinux.o.map FORCE + $(call if_changed,modules_builtin_ranges) + +vmlinux.map: vmlinux + @: + +endif + # Add FORCE to the prerequisites of a target to force it to be always rebuilt. # --------------------------------------------------------------------------- -- cgit v1.2.3 From 1198c9c689cfdaa2d08eb508c13ff116043f07b7 Mon Sep 17 00:00:00 2001 From: Naveen N Rao Date: Wed, 30 Oct 2024 12:38:44 +0530 Subject: kbuild: Add generic hook for architectures to use before the final vmlinux link On powerpc, we would like to be able to make a pass on vmlinux.o and generate a new object file to be linked into vmlinux. Add a generic pass in Makefile.vmlinux that architectures can use for this purpose. Architectures need to select CONFIG_ARCH_WANTS_PRE_LINK_VMLINUX and must provide arch//tools/Makefile with .arch.vmlinux.o target, which will be invoked prior to the final vmlinux link step. Acked-by: Masahiro Yamada Signed-off-by: Naveen N Rao Signed-off-by: Hari Bathini Signed-off-by: Michael Ellerman Link: https://patch.msgid.link/20241030070850.1361304-12-hbathini@linux.ibm.com --- scripts/Makefile.vmlinux | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'scripts/Makefile.vmlinux') diff --git a/scripts/Makefile.vmlinux b/scripts/Makefile.vmlinux index 1284f05555b9..dddad554e912 100644 --- a/scripts/Makefile.vmlinux +++ b/scripts/Makefile.vmlinux @@ -22,6 +22,13 @@ targets += .vmlinux.export.o vmlinux: .vmlinux.export.o endif +ifdef CONFIG_ARCH_WANTS_PRE_LINK_VMLINUX +vmlinux: arch/$(SRCARCH)/tools/vmlinux.arch.o + +arch/$(SRCARCH)/tools/vmlinux.arch.o: vmlinux.o FORCE + $(Q)$(MAKE) $(build)=arch/$(SRCARCH)/tools $@ +endif + ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink) # Final link of vmlinux with optional arch pass after final link -- cgit v1.2.3 From 654102df2ac2a0d02a416100c3d44ff1dae932ca Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 23 Sep 2024 16:56:03 +0900 Subject: kbuild: add generic support for built-in boot DTBs Some architectures embed boot DTBs in vmlinux. A potential issue for these architectures is a race condition during parallel builds because Kbuild descends into arch/*/boot/dts/ twice. One build thread is initiated by the 'dtbs' target, which is a prerequisite of the 'all' target in the top-level Makefile: ifdef CONFIG_OF_EARLY_FLATTREE all: dtbs endif For architectures that support the built-in boot dtb, arch/*/boot/dts/ is visited also during the ordinary directory traversal in order to build obj-y objects that wrap DTBs. Since these build threads are unaware of each other, they can run simultaneously during parallel builds. This commit introduces a generic build rule to scripts/Makefile.vmlinux to support embedded boot DTBs in a race-free way. Architectures that want to use this rule need to select CONFIG_GENERIC_BUILTIN_DTB. After the migration, Makefiles under arch/*/boot/dts/ will be visited only once to build only *.dtb files. This change also aims to unify the CONFIG options used for built-in DTBs support. Currently, different architectures use different CONFIG options for 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 --- scripts/Makefile.vmlinux | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) (limited to 'scripts/Makefile.vmlinux') diff --git a/scripts/Makefile.vmlinux b/scripts/Makefile.vmlinux index 1284f05555b9..9ef0480ed755 100644 --- a/scripts/Makefile.vmlinux +++ b/scripts/Makefile.vmlinux @@ -17,6 +17,50 @@ quiet_cmd_cc_o_c = CC $@ %.o: %.c FORCE $(call if_changed_dep,cc_o_c) +quiet_cmd_as_o_S = AS $@ + cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $< + +%.o: %.S FORCE + $(call if_changed_dep,as_o_S) + +# Built-in dtb +# --------------------------------------------------------------------------- + +quiet_cmd_wrap_dtbs = WRAP $@ + cmd_wrap_dtbs = { \ + echo '\#include '; \ + echo '.section .dtb.init.rodata,"a"'; \ + while read dtb; do \ + symbase=__dtb_$$(basename -s .dtb "$${dtb}" | tr - _); \ + echo '.balign STRUCT_ALIGNMENT'; \ + echo ".global $${symbase}_begin"; \ + echo "$${symbase}_begin:"; \ + echo '.incbin "'$$dtb'" '; \ + echo ".global $${symbase}_end"; \ + echo "$${symbase}_end:"; \ + done < $<; \ + } > $@ + +.builtin-dtbs.S: .builtin-dtbs-list FORCE + $(call if_changed,wrap_dtbs) + +quiet_cmd_gen_dtbs_list = GEN $@ + cmd_gen_dtbs_list = \ + $(if $(CONFIG_BUILTIN_DTB_NAME), echo "arch/$(SRCARCH)/boot/dts/$(CONFIG_BUILTIN_DTB_NAME).dtb",:) > $@ + +.builtin-dtbs-list: arch/$(SRCARCH)/boot/dts/dtbs-list FORCE + $(call if_changed,$(if $(CONFIG_BUILTIN_DTB_ALL),copy,gen_dtbs_list)) + +targets += .builtin-dtbs-list + +ifdef CONFIG_GENERIC_BUILTIN_DTB +targets += .builtin-dtbs.S .builtin-dtbs.o +vmlinux: .builtin-dtbs.o +endif + +# vmlinux +# --------------------------------------------------------------------------- + ifdef CONFIG_MODULES targets += .vmlinux.export.o vmlinux: .vmlinux.export.o -- cgit v1.2.3 From 000e22a80de0727839bb753159ac05c8ba20c3e3 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 14 Nov 2024 08:45:21 +0900 Subject: kbuild: move cmd_cc_o_c and cmd_as_o_S to scripts/Malefile.lib The cmd_cc_o_c and cmd_as_o_S macros are duplicated in scripts/Makefile.{build,modfinal,vmlinux}. This commit factors them out to scripts/Makefile.lib. No functional changes are intended. Signed-off-by: Masahiro Yamada --- scripts/Makefile.vmlinux | 8 -------- 1 file changed, 8 deletions(-) (limited to 'scripts/Makefile.vmlinux') diff --git a/scripts/Makefile.vmlinux b/scripts/Makefile.vmlinux index 9ef0480ed755..2ce61f6c79c6 100644 --- a/scripts/Makefile.vmlinux +++ b/scripts/Makefile.vmlinux @@ -5,21 +5,13 @@ __default: vmlinux include include/config/auto.conf include $(srctree)/scripts/Kbuild.include - -# for c_flags include $(srctree)/scripts/Makefile.lib targets := -quiet_cmd_cc_o_c = CC $@ - cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< - %.o: %.c FORCE $(call if_changed_dep,cc_o_c) -quiet_cmd_as_o_S = AS $@ - cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $< - %.o: %.S FORCE $(call if_changed_dep,as_o_S) -- cgit v1.2.3 From bede169618c68379e1be7ace14e8ac85b964a9ec Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 14 Nov 2024 08:45:22 +0900 Subject: kbuild: enable objtool for *.mod.o and additional kernel objects Currently, objtool is disabled in scripts/Makefile.{modfinal,vmlinux}. This commit moves rule_cc_o_c and rule_as_o_S to scripts/Makefile.lib and set objtool-enabled to y there. With this change, *.mod.o, .module-common.o, builtin-dtb.o, and vmlinux.export.o will now be covered by objtool. Signed-off-by: Masahiro Yamada --- scripts/Makefile.vmlinux | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'scripts/Makefile.vmlinux') diff --git a/scripts/Makefile.vmlinux b/scripts/Makefile.vmlinux index 2ce61f6c79c6..997be5dc7bf5 100644 --- a/scripts/Makefile.vmlinux +++ b/scripts/Makefile.vmlinux @@ -10,10 +10,10 @@ include $(srctree)/scripts/Makefile.lib targets := %.o: %.c FORCE - $(call if_changed_dep,cc_o_c) + $(call if_changed_rule,cc_o_c) %.o: %.S FORCE - $(call if_changed_dep,as_o_S) + $(call if_changed_rule,as_o_S) # Built-in dtb # --------------------------------------------------------------------------- -- cgit v1.2.3 From 18e9944e56f68423e52505066f79939e7d12a62b Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= Date: Sat, 23 Nov 2024 14:33:37 +0100 Subject: kbuild: add dependency from vmlinux to resolve_btfids MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit resolve_btfids is used by link-vmlinux.sh. In contrast to other configuration options and targets no transitive dependency between resolve_btfids and vmlinux. Add an explicit one. Signed-off-by: Thomas Weißschuh Acked-by: Jiri Olsa Signed-off-by: Masahiro Yamada --- scripts/Makefile.vmlinux | 3 +++ 1 file changed, 3 insertions(+) (limited to 'scripts/Makefile.vmlinux') diff --git a/scripts/Makefile.vmlinux b/scripts/Makefile.vmlinux index 997be5dc7bf5..2ecd350e9c43 100644 --- a/scripts/Makefile.vmlinux +++ b/scripts/Makefile.vmlinux @@ -68,6 +68,9 @@ cmd_link_vmlinux = \ targets += vmlinux vmlinux: scripts/link-vmlinux.sh vmlinux.o $(KBUILD_LDS) FORCE +$(call if_changed_dep,link_vmlinux) +ifdef CONFIG_DEBUG_INFO_BTF +vmlinux: $(RESOLVE_BTFIDS) +endif # module.builtin.ranges # --------------------------------------------------------------------------- -- cgit v1.2.3