On Thu, 18 Jul 2019 16:20:41 +0200, Ilya Leoshkevich wrote: > Hi Lorenz, > > I've been using the following patch for quite some time now. > Please let me know if it works for you. > > Best regards, > Ilya > > --- > > When OUTPUT is set, bpftool and libbpf put their objects into the same > directory, and since some of them have the same names, the collision > happens. > > Fix by invoking libbpf build in a manner similar to $(call descend) - > descend itself cannot be used, since libbpf is a sibling, and not a > child, of bpftool. > > Also, don't link bpftool with libbpf.a twice. > > Signed-off-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx> > --- > tools/bpf/bpftool/Makefile | 17 ++++++----------- > 1 file changed, 6 insertions(+), 11 deletions(-) > > diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile > index a7afea4dec47..2cbc3c166f44 100644 > --- a/tools/bpf/bpftool/Makefile > +++ b/tools/bpf/bpftool/Makefile > @@ -15,23 +15,18 @@ else > endif > > BPF_DIR = $(srctree)/tools/lib/bpf/ > - > -ifneq ($(OUTPUT),) > - BPF_PATH = $(OUTPUT) > -else > - BPF_PATH = $(BPF_DIR) > -endif > - > -LIBBPF = $(BPF_PATH)libbpf.a > +BPF_PATH = $(objtree)/tools/lib/bpf objtree won't be set for simple make in the directory. Perhaps we should stick to using OUTPUT and srctree? We should probably make a script with all the ways of calling make should work. Otherwise we can lose track too easily. # thru kbuild make tools/bpf T=$(mktemp -d) make tools/bpf OUTPUT=$T rm -rf $T # from kernel source tree make -C tools/bpf/bpftool T=$(mktemp -d) make -C tools/bpf/bpftool OUTPUT=$T rm -rf $T # from tools cd tools/ make bpf T=$(mktemp -d) make bpf OUTPUT=$T rm -rf $T # from bpftool's dir cd bpf/bpftool make T=$(mktemp -d) make OUTPUT=$T rm -rf $T .. add your own. > +LIBBPF = $(BPF_PATH)/libbpf.a > > BPFTOOL_VERSION := $(shell make --no-print-directory -sC ../../.. kernelversion) > > $(LIBBPF): FORCE > - $(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(OUTPUT) $(OUTPUT)libbpf.a > + $(Q)mkdir -p $(BPF_PATH) > + $(Q)$(MAKE) $(COMMAND_O) subdir=tools/lib/bpf -C $(BPF_DIR) $(LIBBPF) > > $(LIBBPF)-clean: > $(call QUIET_CLEAN, libbpf) > - $(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(OUTPUT) clean >/dev/null > + $(Q)$(MAKE) $(COMMAND_O) subdir=tools/lib/bpf -C $(BPF_DIR) clean >/dev/null > > prefix ?= /usr/local > bash_compdir ?= /usr/share/bash-completion/completions > @@ -112,7 +107,7 @@ $(OUTPUT)disasm.o: $(srctree)/kernel/bpf/disasm.c > $(QUIET_CC)$(COMPILE.c) -MMD -o $@ $< > > $(OUTPUT)bpftool: $(OBJS) $(LIBBPF) > - $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $^ $(LIBS) > + $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $(OBJS) $(LIBS) > > $(OUTPUT)%.o: %.c > $(QUIET_CC)$(COMPILE.c) -MMD -o $@ $<
