kbuild: explicitly specify the build id style

ld's --build-id defaults to "sha1" style, while lld defaults to "fast".
The build IDs are very different between the two, which may confuse
programs that reference them.
Signed-off-by: NBill Wendling <morbo@google.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>

Makefile

@@ -982,8 +982,8 @@ KBUILD_CPPFLAGS += $(KCPPFLAGS)
 KBUILD_AFLAGS   += $(KAFLAGS)
 KBUILD_CFLAGS   += $(KCFLAGS)
 
-KBUILD_LDFLAGS_MODULE += --build-id
-LDFLAGS_vmlinux += --build-id
+KBUILD_LDFLAGS_MODULE += --build-id=sha1
+LDFLAGS_vmlinux += --build-id=sha1
 
 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
 LDFLAGS_vmlinux	+= $(call ld-option, -X,)

arch/arm/vdso/Makefile

@@ -19,7 +19,7 @@ ccflags-y += -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO32
 ldflags-$(CONFIG_CPU_ENDIAN_BE8) := --be8
 ldflags-y := -Bsymbolic --no-undefined -soname=linux-vdso.so.1 \
 	    -z max-page-size=4096 -nostdlib -shared $(ldflags-y) \
-	    --hash-style=sysv --build-id \
+	    --hash-style=sysv --build-id=sha1 \
 	    -T
 
 obj-$(CONFIG_VDSO) += vdso.o

arch/arm64/kernel/vdso/Makefile

@@ -24,7 +24,7 @@ btildflags-$(CONFIG_ARM64_BTI_KERNEL) += -z force-bti
 # routines, as x86 does (see 6f121e548f83 ("x86, vdso: Reimplement vdso.so
 # preparation in build-time C")).
 ldflags-y := -shared -nostdlib -soname=linux-vdso.so.1 --hash-style=sysv	\
-	     -Bsymbolic $(call ld-option, --no-eh-frame-hdr) --build-id -n	\
+	     -Bsymbolic $(call ld-option, --no-eh-frame-hdr) --build-id=sha1 -n	\
 	     $(btildflags-y) -T
 
 ccflags-y := -fno-common -fno-builtin -fno-stack-protector -ffixed-x18

arch/arm64/kernel/vdso32/Makefile

@@ -128,7 +128,7 @@ VDSO_LDFLAGS += -Wl,-Bsymbolic -Wl,--no-undefined -Wl,-soname=linux-vdso.so.1
 VDSO_LDFLAGS += -Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096
 VDSO_LDFLAGS += -nostdlib -shared -mfloat-abi=soft
 VDSO_LDFLAGS += -Wl,--hash-style=sysv
-VDSO_LDFLAGS += -Wl,--build-id
+VDSO_LDFLAGS += -Wl,--build-id=sha1
 VDSO_LDFLAGS += $(call cc32-ldoption,-fuse-ld=bfd)
 
 

arch/mips/vdso/Makefile

@@ -61,7 +61,7 @@ endif
 # VDSO linker flags.
 ldflags-y := -Bsymbolic --no-undefined -soname=linux-vdso.so.1 \
 	$(filter -E%,$(KBUILD_CFLAGS)) -nostdlib -shared \
-	-G 0 --eh-frame-hdr --hash-style=sysv --build-id -T
+	-G 0 --eh-frame-hdr --hash-style=sysv --build-id=sha1 -T
 
 CFLAGS_REMOVE_vdso.o = -pg
 

arch/riscv/kernel/vdso/Makefile

@@ -49,7 +49,7 @@ $(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso) FORCE
 # refer to these symbols in the kernel code rather than hand-coded addresses.
 
 SYSCFLAGS_vdso.so.dbg = -shared -s -Wl,-soname=linux-vdso.so.1 \
-	-Wl,--build-id -Wl,--hash-style=both
+	-Wl,--build-id=sha1 -Wl,--hash-style=both
 $(obj)/vdso-dummy.o: $(src)/vdso.lds $(obj)/rt_sigreturn.o FORCE
 	$(call if_changed,vdsold)
 

arch/s390/kernel/vdso64/Makefile

@@ -19,7 +19,7 @@ KBUILD_AFLAGS_64 += -m64 -s
 KBUILD_CFLAGS_64 := $(filter-out -m64,$(KBUILD_CFLAGS))
 KBUILD_CFLAGS_64 += -m64 -fPIC -shared -fno-common -fno-builtin
 ldflags-y := -fPIC -shared -nostdlib -soname=linux-vdso64.so.1 \
-	     --hash-style=both --build-id -T
+	     --hash-style=both --build-id=sha1 -T
 
 $(targets:%=$(obj)/%.dbg): KBUILD_CFLAGS = $(KBUILD_CFLAGS_64)
 $(targets:%=$(obj)/%.dbg): KBUILD_AFLAGS = $(KBUILD_AFLAGS_64)

arch/sparc/vdso/Makefile

@@ -115,7 +115,7 @@ quiet_cmd_vdso = VDSO    $@
 		       -T $(filter %.lds,$^) $(filter %.o,$^) && \
 		sh $(srctree)/$(src)/checkundef.sh '$(OBJDUMP)' '$@'
 
-VDSO_LDFLAGS = -shared --hash-style=both --build-id -Bsymbolic
+VDSO_LDFLAGS = -shared --hash-style=both --build-id=sha1 -Bsymbolic
 GCOV_PROFILE := n
 
 #

arch/x86/entry/vdso/Makefile

@@ -176,7 +176,7 @@ quiet_cmd_vdso = VDSO    $@
 		       -T $(filter %.lds,$^) $(filter %.o,$^) && \
 		 sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@'
 
-VDSO_LDFLAGS = -shared --hash-style=both --build-id \
+VDSO_LDFLAGS = -shared --hash-style=both --build-id=sha1 \
 	$(call ld-option, --eh-frame-hdr) -Bsymbolic
 GCOV_PROFILE := n
 

tools/testing/selftests/bpf/Makefile

@@ -133,7 +133,7 @@ $(OUTPUT)/%:%.c
 
 $(OUTPUT)/urandom_read: urandom_read.c
 	$(call msg,BINARY,,$@)
-	$(Q)$(CC) $(LDFLAGS) -o $@ $< $(LDLIBS) -Wl,--build-id
+	$(Q)$(CC) $(LDFLAGS) -o $@ $< $(LDLIBS) -Wl,--build-id=sha1
 
 $(OUTPUT)/test_stub.o: test_stub.c $(BPFOBJ)
 	$(call msg,CC,,$@)