Makefile: remove redundant tool coverage variables

masahir0y · masahir0y · commit 7f7f6f7ad654 · 2024-05-14T23:35:48.000+09:00
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 &lt;masahiroy@kernel.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Tested-by: Roberto Sassu &lt;roberto.sassu@huawei.com&gt;
diff --git a/arch/arm/boot/bootp/Makefile b/arch/arm/boot/bootp/Makefile
@@ -5,7 +5,6 @@
 # This file is included by the global makefile so that you can add your own
 # architecture-specific flags and dependencies.
 #
-GCOV_PROFILE	:= n
 
 ifdef PHYS_OFFSET
 add_hex = $(shell printf 0x%x $$(( $(1) + $(2) )) )
diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile
@@ -22,13 +22,6 @@ ifeq ($(CONFIG_ARM_VIRT_EXT),y)
 OBJS		+= hyp-stub.o
 endif
 
-GCOV_PROFILE		:= n
-KASAN_SANITIZE		:= n
-
-# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
-KCOV_INSTRUMENT		:= n
-UBSAN_SANITIZE		:= n
-
 #
 # Architecture dependencies
 #
diff --git a/arch/arm/vdso/Makefile b/arch/arm/vdso/Makefile
@@ -33,15 +33,6 @@ else
 CFLAGS_vgettimeofday.o = -O2 -include $(c-gettimeofday-y)
 endif
 
-# Disable gcov profiling for VDSO code
-GCOV_PROFILE := n
-UBSAN_SANITIZE := n
-
-# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
-KCOV_INSTRUMENT := n
-
-KASAN_SANITIZE := n
-
 # Force dependency
 $(obj)/vdso.o : $(obj)/vdso.so
 
diff --git a/arch/arm64/kernel/pi/Makefile b/arch/arm64/kernel/pi/Makefile
@@ -19,12 +19,6 @@ KBUILD_CFLAGS	:= $(filter-out $(CC_FLAGS_SCS), $(KBUILD_CFLAGS))
 # disable LTO
 KBUILD_CFLAGS	:= $(filter-out $(CC_FLAGS_LTO), $(KBUILD_CFLAGS))
 
-GCOV_PROFILE	:= n
-KASAN_SANITIZE	:= n
-KCSAN_SANITIZE	:= n
-UBSAN_SANITIZE	:= n
-KCOV_INSTRUMENT	:= n
-
 hostprogs	:= relacheck
 
 quiet_cmd_piobjcopy = $(quiet_cmd_objcopy)
diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile
@@ -40,21 +40,13 @@ CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) \
 				$(RANDSTRUCT_CFLAGS) $(GCC_PLUGINS_CFLAGS) \
 				$(CC_FLAGS_LTO) $(CC_FLAGS_CFI) \
 				-Wmissing-prototypes -Wmissing-declarations
-KASAN_SANITIZE			:= n
-KCSAN_SANITIZE			:= n
-UBSAN_SANITIZE			:= n
-OBJECT_FILES_NON_STANDARD	:= y
-KCOV_INSTRUMENT			:= n
 
 CFLAGS_vgettimeofday.o = -O2 -mcmodel=tiny -fasynchronous-unwind-tables
 
 ifneq ($(c-gettimeofday-y),)
   CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y)
 endif
 
-# Disable gcov profiling for VDSO code
-GCOV_PROFILE := n
-
 targets += vdso.lds
 CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
 
diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile
@@ -97,16 +97,3 @@ KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) $(CC_FLAGS_CFI)
 # causes a build failure. Remove profile optimization flags.
 KBUILD_CFLAGS := $(filter-out -fprofile-sample-use=% -fprofile-use=%, $(KBUILD_CFLAGS))
 KBUILD_CFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables
-
-# KVM nVHE code is run at a different exception code with a different map, so
-# compiler instrumentation that inserts callbacks or checks into the code may
-# cause crashes. Just disable it.
-GCOV_PROFILE	:= n
-KASAN_SANITIZE	:= n
-KCSAN_SANITIZE	:= n
-UBSAN_SANITIZE	:= n
-KCOV_INSTRUMENT	:= n
-
-# Skip objtool checking for this directory because nVHE code is compiled with
-# non-standard build rules.
-OBJECT_FILES_NON_STANDARD := y
diff --git a/arch/csky/kernel/vdso/Makefile b/arch/csky/kernel/vdso/Makefile
@@ -23,10 +23,6 @@ obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
 obj-y += vdso.o vdso-syms.o
 CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
 
-# Disable gcov profiling for VDSO code
-GCOV_PROFILE := n
-KCOV_INSTRUMENT := n
-
 # Force dependency
 $(obj)/vdso.o: $(obj)/vdso.so
 
diff --git a/arch/loongarch/vdso/Makefile b/arch/loongarch/vdso/Makefile
@@ -1,11 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 # Objects to go into the VDSO.
 
-KASAN_SANITIZE := n
-UBSAN_SANITIZE := n
-KCOV_INSTRUMENT := n
-OBJECT_FILES_NON_STANDARD := y
-
 # Include the generic Makefile to check the built vdso.
 include $(srctree)/lib/vdso/Makefile
 
@@ -39,8 +34,6 @@ ldflags-y := -Bsymbolic --no-undefined -soname=linux-vdso.so.1 \
 	$(filter -E%,$(KBUILD_CFLAGS)) -nostdlib -shared \
 	--hash-style=sysv --build-id -T
 
-GCOV_PROFILE := n
-
 #
 # Shared build commands.
 #
diff --git a/arch/mips/boot/compressed/Makefile b/arch/mips/boot/compressed/Makefile
@@ -34,12 +34,6 @@ KBUILD_AFLAGS := $(KBUILD_AFLAGS) -D__ASSEMBLY__ \
 	-DBOOT_HEAP_SIZE=$(BOOT_HEAP_SIZE) \
 	-DKERNEL_ENTRY=$(VMLINUX_ENTRY_ADDRESS)
 
-# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
-KCOV_INSTRUMENT		:= n
-GCOV_PROFILE := n
-UBSAN_SANITIZE := n
-KCSAN_SANITIZE			:= n
-
 # decompressor objects (linked with vmlinuz)
 vmlinuzobjs-y := $(obj)/head.o $(obj)/decompress.o $(obj)/string.o $(obj)/bswapsi.o
 
diff --git a/arch/mips/vdso/Makefile b/arch/mips/vdso/Makefile
@@ -1,9 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 # Objects to go into the VDSO.
 
-# Sanitizer runtimes are unavailable and cannot be linked here.
- KCSAN_SANITIZE			:= n
-
 # Include the generic Makefile to check the built vdso.
 include $(srctree)/lib/vdso/Makefile
 
@@ -60,10 +57,6 @@ ldflags-y := -Bsymbolic --no-undefined -soname=linux-vdso.so.1 \
 
 CFLAGS_REMOVE_vdso.o = $(CC_FLAGS_FTRACE)
 
-GCOV_PROFILE := n
-UBSAN_SANITIZE := n
-KCOV_INSTRUMENT := n
-
 # Check that we don't have PIC 'jalr t9' calls left
 quiet_cmd_vdso_mips_check = VDSOCHK $@
       cmd_vdso_mips_check = if $(OBJDUMP) --disassemble $@ | grep -E -h "jalr.*t9" > /dev/null; \
diff --git a/arch/parisc/boot/compressed/Makefile b/arch/parisc/boot/compressed/Makefile
@@ -5,10 +5,6 @@
 # create a compressed self-extracting vmlinux image from the original vmlinux
 #
 
-KCOV_INSTRUMENT := n
-GCOV_PROFILE := n
-UBSAN_SANITIZE := n
-
 OBJECTS := head.o real2.o firmware.o misc.o piggy.o
 targets := vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2
 targets += vmlinux.bin.xz vmlinux.bin.lzma vmlinux.bin.lzo vmlinux.bin.lz4
diff --git a/arch/powerpc/kernel/vdso/Makefile b/arch/powerpc/kernel/vdso/Makefile
@@ -47,12 +47,6 @@ obj-vdso32 := $(addprefix $(obj)/, $(obj-vdso32))
 targets += $(obj-vdso64) vdso64.so.dbg vgettimeofday-64.o
 obj-vdso64 := $(addprefix $(obj)/, $(obj-vdso64))
 
-GCOV_PROFILE := n
-KCOV_INSTRUMENT := n
-UBSAN_SANITIZE := n
-KASAN_SANITIZE := n
-KCSAN_SANITIZE := n
-
 ccflags-y := -fno-common -fno-builtin
 ldflags-y := -Wl,--hash-style=both -nostdlib -shared -z noexecstack $(CLANG_FLAGS)
 ldflags-$(CONFIG_LD_IS_LLD) += $(call cc-option,--ld-path=$(LD),-fuse-ld=lld)
@@ -114,5 +108,3 @@ quiet_cmd_vdso64ld_and_check = VDSO64L $@
       cmd_vdso64ld_and_check = $(VDSOCC) $(ldflags-y) $(LD64FLAGS) -o $@ -Wl,-T$(filter %.lds,$^) $(filter %.o,$^); $(cmd_vdso_check)
 quiet_cmd_vdso64as = VDSO64A $@
       cmd_vdso64as = $(VDSOCC) $(a_flags) $(AS64FLAGS) -c -o $@ $<
-
-OBJECT_FILES_NON_STANDARD := y
diff --git a/arch/powerpc/purgatory/Makefile b/arch/powerpc/purgatory/Makefile
@@ -1,8 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
 
-KASAN_SANITIZE := n
-KCSAN_SANITIZE := n
-
 targets += trampoline_$(BITS).o purgatory.ro
 
 # When profile-guided optimization is enabled, llvm emits two different
diff --git a/arch/riscv/boot/Makefile b/arch/riscv/boot/Makefile
@@ -14,8 +14,6 @@
 # Based on the ia64 and arm64 boot/Makefile.
 #
 
-KCOV_INSTRUMENT := n
-
 OBJCOPYFLAGS_Image :=-O binary -R .note -R .note.gnu.build-id -R .comment -S
 OBJCOPYFLAGS_loader.bin :=-O binary
 OBJCOPYFLAGS_xipImage :=-O binary -R .note -R .note.gnu.build-id -R .comment -S
diff --git a/arch/riscv/kernel/compat_vdso/Makefile b/arch/riscv/kernel/compat_vdso/Makefile
@@ -34,12 +34,6 @@ obj-compat_vdso := $(addprefix $(obj)/, $(obj-compat_vdso))
 obj-y += compat_vdso.o
 CPPFLAGS_compat_vdso.lds += -P -C -DCOMPAT_VDSO -U$(ARCH)
 
-# Disable profiling and instrumentation for VDSO code
-GCOV_PROFILE := n
-KCOV_INSTRUMENT := n
-KASAN_SANITIZE := n
-UBSAN_SANITIZE := n
-
 # Force dependency
 $(obj)/compat_vdso.o: $(obj)/compat_vdso.so
 
diff --git a/arch/riscv/kernel/pi/Makefile b/arch/riscv/kernel/pi/Makefile
@@ -17,12 +17,6 @@ KBUILD_CFLAGS	+= -mcmodel=medany
 CFLAGS_cmdline_early.o += -D__NO_FORTIFY
 CFLAGS_lib-fdt_ro.o += -D__NO_FORTIFY
 
-GCOV_PROFILE	:= n
-KASAN_SANITIZE	:= n
-KCSAN_SANITIZE	:= n
-UBSAN_SANITIZE	:= n
-KCOV_INSTRUMENT	:= n
-
 $(obj)/%.pi.o: OBJCOPYFLAGS := --prefix-symbols=__pi_ \
 			       --remove-section=.note.gnu.property \
 			       --prefix-alloc-sections=.init.pi
diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile
@@ -39,12 +39,6 @@ endif
 CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS)
 CFLAGS_REMOVE_hwprobe.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS)
 
-# Disable profiling and instrumentation for VDSO code
-GCOV_PROFILE := n
-KCOV_INSTRUMENT := n
-KASAN_SANITIZE := n
-UBSAN_SANITIZE := n
-
 # Force dependency
 $(obj)/vdso.o: $(obj)/vdso.so
 
diff --git a/arch/riscv/purgatory/Makefile b/arch/riscv/purgatory/Makefile
@@ -1,5 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0
-OBJECT_FILES_NON_STANDARD := y
 
 purgatory-y := purgatory.o sha256.o entry.o string.o ctype.o memcpy.o memset.o
 purgatory-y += strcmp.o strlen.o strncmp.o
@@ -47,13 +46,6 @@ LDFLAGS_purgatory.ro := -r $(PURGATORY_LDFLAGS)
 LDFLAGS_purgatory.chk := $(PURGATORY_LDFLAGS)
 targets += purgatory.ro purgatory.chk
 
-# Sanitizer, etc. runtimes are unavailable and cannot be linked here.
-GCOV_PROFILE	:= n
-KASAN_SANITIZE	:= n
-UBSAN_SANITIZE	:= n
-KCSAN_SANITIZE	:= n
-KCOV_INSTRUMENT := n
-
 # These are adjustments to the compiler flags used for objects that
 # make up the standalone purgatory.ro
 
diff --git a/arch/s390/kernel/vdso32/Makefile b/arch/s390/kernel/vdso32/Makefile
@@ -1,8 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 # List of files in the vdso
 
-KCOV_INSTRUMENT := n
-
 # Include the generic Makefile to check the built vdso.
 include $(srctree)/lib/vdso/Makefile
 obj-vdso32 = vdso_user_wrapper-32.o note-32.o
@@ -32,12 +30,6 @@ obj-y += vdso32_wrapper.o
 targets += vdso32.lds
 CPPFLAGS_vdso32.lds += -P -C -U$(ARCH)
 
-# Disable gcov profiling, ubsan and kasan for VDSO code
-GCOV_PROFILE := n
-UBSAN_SANITIZE := n
-KASAN_SANITIZE := n
-KCSAN_SANITIZE := n
-
 # Force dependency (incbin is bad)
 $(obj)/vdso32_wrapper.o : $(obj)/vdso32.so
 
diff --git a/arch/s390/kernel/vdso64/Makefile b/arch/s390/kernel/vdso64/Makefile
@@ -1,8 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 # List of files in the vdso
 
-KCOV_INSTRUMENT := n
-
 # Include the generic Makefile to check the built vdso.
 include $(srctree)/lib/vdso/Makefile
 obj-vdso64 = vdso_user_wrapper.o note.o
@@ -37,12 +35,6 @@ obj-y += vdso64_wrapper.o
 targets += vdso64.lds
 CPPFLAGS_vdso64.lds += -P -C -U$(ARCH)
 
-# Disable gcov profiling, ubsan and kasan for VDSO code
-GCOV_PROFILE := n
-UBSAN_SANITIZE := n
-KASAN_SANITIZE := n
-KCSAN_SANITIZE := n
-
 # Force dependency (incbin is bad)
 $(obj)/vdso64_wrapper.o : $(obj)/vdso64.so
 
diff --git a/arch/s390/purgatory/Makefile b/arch/s390/purgatory/Makefile
@@ -1,7 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
 
-OBJECT_FILES_NON_STANDARD := y
-
 purgatory-y := head.o purgatory.o string.o sha256.o mem.o
 
 targets += $(purgatory-y) purgatory.lds purgatory purgatory.chk purgatory.ro
@@ -15,12 +13,6 @@ CFLAGS_sha256.o := -D__DISABLE_EXPORTS -D__NO_FORTIFY
 $(obj)/mem.o: $(srctree)/arch/s390/lib/mem.S FORCE
 	$(call if_changed_rule,as_o_S)
 
-KCOV_INSTRUMENT := n
-GCOV_PROFILE := n
-UBSAN_SANITIZE := n
-KASAN_SANITIZE := n
-KCSAN_SANITIZE := n
-
 KBUILD_CFLAGS := -fno-strict-aliasing -Wall -Wstrict-prototypes
 KBUILD_CFLAGS += -Wno-pointer-sign -Wno-sign-compare
 KBUILD_CFLAGS += -fno-zero-initialized-in-bss -fno-builtin -ffreestanding
diff --git a/arch/sh/boot/compressed/Makefile b/arch/sh/boot/compressed/Makefile
@@ -11,9 +11,6 @@ OBJECTS := head_32.o misc.o cache.o piggy.o \
 targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 \
            vmlinux.bin.lzma vmlinux.bin.xz vmlinux.bin.lzo $(OBJECTS)
 
-GCOV_PROFILE := n
-UBSAN_SANITIZE := n
-
 #
 # IMAGE_OFFSET is the load offset of the compression loader
 #
diff --git a/arch/sparc/vdso/Makefile b/arch/sparc/vdso/Makefile
@@ -2,7 +2,6 @@
 #
 # Building vDSO images for sparc.
 #
-UBSAN_SANITIZE := n
 
 # files to link into the vdso
 vobjs-y := vdso-note.o vclock_gettime.o
@@ -106,4 +105,3 @@ quiet_cmd_vdso = VDSO    $@
 		sh $(src)/checkundef.sh '$(OBJDUMP)' '$@'
 
 VDSO_LDFLAGS = -shared --hash-style=both --build-id=sha1 -Bsymbolic
-GCOV_PROFILE := n
diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile
@@ -9,19 +9,6 @@
 # Changed by many, many contributors over the years.
 #
 
-# Sanitizer runtimes are unavailable and cannot be linked for early boot code.
-KASAN_SANITIZE			:= n
-KCSAN_SANITIZE			:= n
-KMSAN_SANITIZE			:= n
-OBJECT_FILES_NON_STANDARD	:= y
-
-# Kernel does not boot with kcov instrumentation here.
-# One of the problems observed was insertion of __sanitizer_cov_trace_pc()
-# callback into middle of per-cpu data enabling code. Thus the callback observed
-# inconsistent state and crashed. We are interested mostly in syscall coverage,
-# so boot code is not interesting anyway.
-KCOV_INSTRUMENT		:= n
-
 # If you want to preset the SVGA mode, uncomment the next line and
 # set SVGA_MODE to whatever number you want.
 # Set it to -DSVGA_MODE=NORMAL_VGA if you just want the EGA/VGA mode.
@@ -69,8 +56,6 @@ KBUILD_CFLAGS	:= $(REALMODE_CFLAGS) -D_SETUP
 KBUILD_AFLAGS	:= $(KBUILD_CFLAGS) -D__ASSEMBLY__
 KBUILD_CFLAGS	+= $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
 KBUILD_CFLAGS	+= -fno-asynchronous-unwind-tables
-GCOV_PROFILE := n
-UBSAN_SANITIZE := n
 
 $(obj)/bzImage: asflags-y  := $(SVGA_MODE)
 
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile
diff --git a/arch/x86/purgatory/Makefile b/arch/x86/purgatory/Makefile
diff --git a/arch/x86/realmode/rm/Makefile b/arch/x86/realmode/rm/Makefile
diff --git a/arch/x86/um/vdso/Makefile b/arch/x86/um/vdso/Makefile
diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
diff --git a/drivers/misc/lkdtm/Makefile b/drivers/misc/lkdtm/Makefile
diff --git a/init/Makefile b/init/Makefile
diff --git a/scripts/Makefile.vmlinux b/scripts/Makefile.vmlinux
diff --git a/scripts/mod/Makefile b/scripts/mod/Makefile

Original file line number	Diff line number	Diff line change
`@@ -5,7 +5,6 @@`
`5`	`5`	`# This file is included by the global makefile so that you can add your own`
`6`	`6`	`# architecture-specific flags and dependencies.`
`7`	`7`	`#`
`8`		`-GCOV_PROFILE := n`
`9`	`8`
`10`	`9`	`ifdef PHYS_OFFSET`
`11`	`10`	`add_hex = $(shell printf 0x%x $$(( $(1) + $(2) )) )`
Original file line number	Diff line number	Diff line change
`@@ -22,13 +22,6 @@ ifeq ($(CONFIG_ARM_VIRT_EXT),y)`
`22`	`22`	`OBJS += hyp-stub.o`
`23`	`23`	`endif`
`24`	`24`
`25`		`-GCOV_PROFILE := n`
`26`		`-KASAN_SANITIZE := n`
`27`		`-`
`28`		`-# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.`
`29`		`-KCOV_INSTRUMENT := n`
`30`		`-UBSAN_SANITIZE := n`
`31`		`-`
`32`	`25`	`#`
`33`	`26`	`# Architecture dependencies`
`34`	`27`	`#`