From: Quentin Monnet quentin.monnet@netronome.com
[ Upstream commit a89b2cbf71d64b61e79bbe5cb7ff4664797eeaaf ]
Building selftests with 'make TARGETS=bpf kselftest' was fixed in commit 55d554f5d140 ("tools: bpf: Use !building_out_of_srctree to determine srctree"). However, by updating $(srctree) in tools/bpf/Makefile for in-tree builds only, we leave out the case where we pass an output directory to build BPF tools, but $(srctree) is not set. This typically happens for:
$ make -s tools/bpf O=/tmp/foo Makefile:40: /tools/build/Makefile.feature: No such file or directory
Fix it by updating $(srctree) in the Makefile not only for out-of-tree builds, but also if $(srctree) is empty.
Detected with test_bpftool_build.sh.
Fixes: 55d554f5d140 ("tools: bpf: Use !building_out_of_srctree to determine srctree") Signed-off-by: Quentin Monnet quentin.monnet@netronome.com Signed-off-by: Daniel Borkmann daniel@iogearbox.net Acked-by: Jakub Kicinski jakub.kicinski@netronome.com Link: https://lore.kernel.org/bpf/20191119105626.21453-1-quentin.monnet@netronome.... Signed-off-by: Sasha Levin sashal@kernel.org --- tools/bpf/Makefile | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/tools/bpf/Makefile b/tools/bpf/Makefile index 5d1995fd369c6..5535650800ab2 100644 --- a/tools/bpf/Makefile +++ b/tools/bpf/Makefile @@ -16,7 +16,13 @@ CFLAGS += -D__EXPORTED_HEADERS__ -I$(srctree)/include/uapi -I$(srctree)/include # isn't set and when invoked from selftests build, where srctree # is set to ".". building_out_of_srctree is undefined for in srctree # builds +ifeq ($(srctree),) +update_srctree := 1 +endif ifndef building_out_of_srctree +update_srctree := 1 +endif +ifeq ($(update_srctree),1) srctree := $(patsubst %/,%,$(dir $(CURDIR))) srctree := $(patsubst %/,%,$(dir $(srctree))) endif