linux/tools/bpf/bpftool/Makefile
Jean-Philippe Brucker 0779890fed tools/bpftool: Fix cross-build
When the bootstrap and final bpftool have different architectures, we
need to build two distinct disasm.o objects. Add a recipe for the
bootstrap disasm.o.

After commit d510296d33 ("bpftool: Use syscall/loader program in
"prog load" and "gen skeleton" command.") cross-building bpftool didn't
work anymore, because the bootstrap bpftool was linked using objects
from different architectures:

  $ make O=/tmp/bpftool ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- -C tools/bpf/bpftool/ V=1
  [...]
  aarch64-linux-gnu-gcc ... -c -MMD -o /tmp/bpftool/disasm.o /home/z/src/linux/kernel/bpf/disasm.c
  gcc ... -c -MMD -o /tmp/bpftool//bootstrap/main.o main.c
  gcc ... -o /tmp/bpftool//bootstrap/bpftool /tmp/bpftool//bootstrap/main.o ... /tmp/bpftool/disasm.o
  /usr/bin/ld: /tmp/bpftool/disasm.o: Relocations in generic ELF (EM: 183)
  /usr/bin/ld: /tmp/bpftool/disasm.o: Relocations in generic ELF (EM: 183)
  /usr/bin/ld: /tmp/bpftool/disasm.o: Relocations in generic ELF (EM: 183)
  /usr/bin/ld: /tmp/bpftool/disasm.o: error adding symbols: file in wrong format
  collect2: error: ld returned 1 exit status
  [...]

The final bpftool was built for e.g. arm64, while the bootstrap bpftool,
executed on the host, was built for x86. The problem here was that disasm.o
linked into the bootstrap bpftool was arm64 rather than x86. With the fix
we build two disasm.o, one for the target bpftool in arm64, and one for
the bootstrap bpftool in x86.

Fixes: d510296d33 ("bpftool: Use syscall/loader program in "prog load" and "gen skeleton" command.")
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210603170515.1854642-1-jean-philippe@linaro.org
2021-06-08 21:59:08 +02:00

250 lines
6.7 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0-only
include ../../scripts/Makefile.include
include ../../scripts/utilities.mak
ifeq ($(srctree),)
srctree := $(patsubst %/,%,$(dir $(CURDIR)))
srctree := $(patsubst %/,%,$(dir $(srctree)))
srctree := $(patsubst %/,%,$(dir $(srctree)))
endif
ifeq ($(V),1)
Q =
else
Q = @
endif
BPF_DIR = $(srctree)/tools/lib/bpf/
ifneq ($(OUTPUT),)
LIBBPF_OUTPUT = $(OUTPUT)/libbpf/
LIBBPF_PATH = $(LIBBPF_OUTPUT)
BOOTSTRAP_OUTPUT = $(OUTPUT)/bootstrap/
else
LIBBPF_OUTPUT =
LIBBPF_PATH = $(BPF_DIR)
BOOTSTRAP_OUTPUT = $(CURDIR)/bootstrap/
endif
LIBBPF = $(LIBBPF_PATH)libbpf.a
LIBBPF_BOOTSTRAP_OUTPUT = $(BOOTSTRAP_OUTPUT)libbpf/
LIBBPF_BOOTSTRAP = $(LIBBPF_BOOTSTRAP_OUTPUT)libbpf.a
ifeq ($(BPFTOOL_VERSION),)
BPFTOOL_VERSION := $(shell make -rR --no-print-directory -sC ../../.. kernelversion)
endif
$(LIBBPF_OUTPUT) $(BOOTSTRAP_OUTPUT) $(LIBBPF_BOOTSTRAP_OUTPUT):
$(QUIET_MKDIR)mkdir -p $@
$(LIBBPF): FORCE | $(LIBBPF_OUTPUT)
$(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(LIBBPF_OUTPUT) $(LIBBPF_OUTPUT)libbpf.a
$(LIBBPF_BOOTSTRAP): FORCE | $(LIBBPF_BOOTSTRAP_OUTPUT)
$(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(LIBBPF_BOOTSTRAP_OUTPUT) \
ARCH= CC=$(HOSTCC) LD=$(HOSTLD) $@
$(LIBBPF)-clean: FORCE | $(LIBBPF_OUTPUT)
$(call QUIET_CLEAN, libbpf)
$(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(LIBBPF_OUTPUT) clean >/dev/null
$(LIBBPF_BOOTSTRAP)-clean: FORCE | $(LIBBPF_BOOTSTRAP_OUTPUT)
$(call QUIET_CLEAN, libbpf-bootstrap)
$(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(LIBBPF_BOOTSTRAP_OUTPUT) clean >/dev/null
prefix ?= /usr/local
bash_compdir ?= /usr/share/bash-completion/completions
CFLAGS += -O2
CFLAGS += -W -Wall -Wextra -Wno-unused-parameter -Wno-missing-field-initializers
CFLAGS += $(filter-out -Wswitch-enum -Wnested-externs,$(EXTRA_WARNINGS))
CFLAGS += -DPACKAGE='"bpftool"' -D__EXPORTED_HEADERS__ \
-I$(if $(OUTPUT),$(OUTPUT),.) \
-I$(srctree)/kernel/bpf/ \
-I$(srctree)/tools/include \
-I$(srctree)/tools/include/uapi \
-I$(srctree)/tools/lib \
-I$(srctree)/tools/perf
CFLAGS += -DBPFTOOL_VERSION='"$(BPFTOOL_VERSION)"'
ifneq ($(EXTRA_CFLAGS),)
CFLAGS += $(EXTRA_CFLAGS)
endif
ifneq ($(EXTRA_LDFLAGS),)
LDFLAGS += $(EXTRA_LDFLAGS)
endif
INSTALL ?= install
RM ?= rm -f
FEATURE_USER = .bpftool
FEATURE_TESTS = libbfd disassembler-four-args reallocarray zlib libcap \
clang-bpf-co-re
FEATURE_DISPLAY = libbfd disassembler-four-args zlib libcap \
clang-bpf-co-re
check_feat := 1
NON_CHECK_FEAT_TARGETS := clean uninstall doc doc-clean doc-install doc-uninstall
ifdef MAKECMDGOALS
ifeq ($(filter-out $(NON_CHECK_FEAT_TARGETS),$(MAKECMDGOALS)),)
check_feat := 0
endif
endif
ifeq ($(check_feat),1)
ifeq ($(FEATURES_DUMP),)
include $(srctree)/tools/build/Makefile.feature
else
include $(FEATURES_DUMP)
endif
endif
ifeq ($(feature-disassembler-four-args), 1)
CFLAGS += -DDISASM_FOUR_ARGS_SIGNATURE
endif
ifeq ($(feature-reallocarray), 0)
CFLAGS += -DCOMPAT_NEED_REALLOCARRAY
endif
LIBS = $(LIBBPF) -lelf -lz
LIBS_BOOTSTRAP = $(LIBBPF_BOOTSTRAP) -lelf -lz
ifeq ($(feature-libcap), 1)
CFLAGS += -DUSE_LIBCAP
LIBS += -lcap
endif
include $(wildcard $(OUTPUT)*.d)
all: $(OUTPUT)bpftool
BFD_SRCS = jit_disasm.c
SRCS = $(filter-out $(BFD_SRCS),$(wildcard *.c))
ifeq ($(feature-libbfd),1)
LIBS += -lbfd -ldl -lopcodes
else ifeq ($(feature-libbfd-liberty),1)
LIBS += -lbfd -ldl -lopcodes -liberty
else ifeq ($(feature-libbfd-liberty-z),1)
LIBS += -lbfd -ldl -lopcodes -liberty -lz
endif
ifneq ($(filter -lbfd,$(LIBS)),)
CFLAGS += -DHAVE_LIBBFD_SUPPORT
SRCS += $(BFD_SRCS)
endif
BPFTOOL_BOOTSTRAP := $(BOOTSTRAP_OUTPUT)bpftool
BOOTSTRAP_OBJS = $(addprefix $(BOOTSTRAP_OUTPUT),main.o common.o json_writer.o gen.o btf.o xlated_dumper.o btf_dumper.o disasm.o)
OBJS = $(patsubst %.c,$(OUTPUT)%.o,$(SRCS)) $(OUTPUT)disasm.o
VMLINUX_BTF_PATHS ?= $(if $(O),$(O)/vmlinux) \
$(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux) \
../../../vmlinux \
/sys/kernel/btf/vmlinux \
/boot/vmlinux-$(shell uname -r)
VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS))))
bootstrap: $(BPFTOOL_BOOTSTRAP)
ifneq ($(VMLINUX_BTF)$(VMLINUX_H),)
ifeq ($(feature-clang-bpf-co-re),1)
BUILD_BPF_SKELS := 1
$(OUTPUT)vmlinux.h: $(VMLINUX_BTF) $(BPFTOOL_BOOTSTRAP)
ifeq ($(VMLINUX_H),)
$(QUIET_GEN)$(BPFTOOL_BOOTSTRAP) btf dump file $< format c > $@
else
$(Q)cp "$(VMLINUX_H)" $@
endif
$(OUTPUT)%.bpf.o: skeleton/%.bpf.c $(OUTPUT)vmlinux.h $(LIBBPF)
$(QUIET_CLANG)$(CLANG) \
-I$(if $(OUTPUT),$(OUTPUT),.) \
-I$(srctree)/tools/include/uapi/ \
-I$(LIBBPF_PATH) \
-I$(srctree)/tools/lib \
-g -O2 -Wall -target bpf -c $< -o $@ && $(LLVM_STRIP) -g $@
$(OUTPUT)%.skel.h: $(OUTPUT)%.bpf.o $(BPFTOOL_BOOTSTRAP)
$(QUIET_GEN)$(BPFTOOL_BOOTSTRAP) gen skeleton $< > $@
$(OUTPUT)prog.o: $(OUTPUT)profiler.skel.h
$(OUTPUT)pids.o: $(OUTPUT)pid_iter.skel.h
endif
endif
CFLAGS += $(if $(BUILD_BPF_SKELS),,-DBPFTOOL_WITHOUT_SKELETONS)
$(BOOTSTRAP_OUTPUT)disasm.o: $(srctree)/kernel/bpf/disasm.c
$(QUIET_CC)$(HOSTCC) $(CFLAGS) -c -MMD -o $@ $<
$(OUTPUT)disasm.o: $(srctree)/kernel/bpf/disasm.c
$(QUIET_CC)$(CC) $(CFLAGS) -c -MMD -o $@ $<
$(OUTPUT)feature.o: | zdep
$(BPFTOOL_BOOTSTRAP): $(BOOTSTRAP_OBJS) $(LIBBPF_BOOTSTRAP)
$(QUIET_LINK)$(HOSTCC) $(CFLAGS) $(LDFLAGS) -o $@ $(BOOTSTRAP_OBJS) \
$(LIBS_BOOTSTRAP)
$(OUTPUT)bpftool: $(OBJS) $(LIBBPF)
$(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $(OBJS) $(LIBS)
$(BOOTSTRAP_OUTPUT)%.o: %.c | $(BOOTSTRAP_OUTPUT)
$(QUIET_CC)$(HOSTCC) $(CFLAGS) -c -MMD -o $@ $<
$(OUTPUT)%.o: %.c
$(QUIET_CC)$(CC) $(CFLAGS) -c -MMD -o $@ $<
feature-detect-clean:
$(call QUIET_CLEAN, feature-detect)
$(Q)$(MAKE) -C $(srctree)/tools/build/feature/ clean >/dev/null
clean: $(LIBBPF)-clean $(LIBBPF_BOOTSTRAP)-clean feature-detect-clean
$(call QUIET_CLEAN, bpftool)
$(Q)$(RM) -- $(OUTPUT)bpftool $(OUTPUT)*.o $(OUTPUT)*.d
$(Q)$(RM) -- $(OUTPUT)*.skel.h $(OUTPUT)vmlinux.h
$(Q)$(RM) -r -- $(LIBBPF_OUTPUT) $(BOOTSTRAP_OUTPUT)
$(call QUIET_CLEAN, core-gen)
$(Q)$(RM) -- $(OUTPUT)FEATURE-DUMP.bpftool
$(Q)$(RM) -r -- $(OUTPUT)feature/
install: $(OUTPUT)bpftool
$(call QUIET_INSTALL, bpftool)
$(Q)$(INSTALL) -m 0755 -d $(DESTDIR)$(prefix)/sbin
$(Q)$(INSTALL) $(OUTPUT)bpftool $(DESTDIR)$(prefix)/sbin/bpftool
$(Q)$(INSTALL) -m 0755 -d $(DESTDIR)$(bash_compdir)
$(Q)$(INSTALL) -m 0644 bash-completion/bpftool $(DESTDIR)$(bash_compdir)
uninstall:
$(call QUIET_UNINST, bpftool)
$(Q)$(RM) -- $(DESTDIR)$(prefix)/sbin/bpftool
$(Q)$(RM) -- $(DESTDIR)$(bash_compdir)/bpftool
doc:
$(call descend,Documentation)
doc-clean:
$(call descend,Documentation,clean)
doc-install:
$(call descend,Documentation,install)
doc-uninstall:
$(call descend,Documentation,uninstall)
FORCE:
zdep:
@if [ "$(feature-zlib)" != "1" ]; then echo "No zlib found"; exit 1 ; fi
.SECONDARY:
.PHONY: all FORCE clean install uninstall zdep
.PHONY: doc doc-clean doc-install doc-uninstall
.DEFAULT_GOAL := all