Re: [PATCH 2/4] selftests/bpf: Install resolve_btfids.test.o.BTF where the test expects it

From: Ricardo B. Marlière

Date: Fri Jul 17 2026 - 13:03:03 EST


On Thu Jul 16, 2026 at 6:10 PM -03, Ihor Solodrai wrote:
> On 7/10/26 3:09 PM, Ricardo B. Marlière wrote:
>> prog_tests/resolve_btfids.c looks for "resolve_btfids.test.o.BTF" relative
>> to the running test_progs binary. resolve_btfids always writes
>> <obj.path>.BTF next to the object it processes, so building
>> resolve_btfids.test.o also produces resolve_btfids.test.o.BTF in the build
>> output directory as a side effect.
>>
>> INSTALL_RULE never carries it over: it is not part of TEST_FILES,
>> TEST_GEN_FILES or TRUNNER_EXTRA_FILES, and it is not copied by the *.bpf.o
>> rsync used for TEST_INST_SUBDIRS. After "make install", every flavor of
>> test_progs, including the default one, fails with "Failed to load BTF from
>> resolve_btfids.test.o.BTF", even though the file built fine and BTF ID
>> resolution itself works correctly.
>>
>> Install it next to the rest of the per-flavor build output, using an
>> explicit rsync in INSTALL_RULE like the one already used for bpftool.
>>
>> Fixes: 522397d05e7d ("resolve_btfids: Change in-place update with raw binary output")
>> Signed-off-by: Ricardo B. Marlière <rbm@xxxxxxxx>
>> ---
>> tools/testing/selftests/bpf/Makefile | 3 ++-
>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
>> index 47911c9b4977..7260d672acf7 100644
>> --- a/tools/testing/selftests/bpf/Makefile
>> +++ b/tools/testing/selftests/bpf/Makefile
>> @@ -1057,10 +1057,11 @@ override define INSTALL_RULE
>> $(DEFAULT_INSTALL_RULE)
>> @mkdir -p $(INSTALL_PATH)/tools/sbin
>> @rsync -a $(if $(PERMISSIVE),--ignore-missing-args) $(TRUNNER_BPFTOOL) $(INSTALL_PATH)/tools/sbin/
>> + @rsync -a $(if $(PERMISSIVE),--ignore-missing-args) $(OUTPUT)/resolve_btfids.test.o.BTF $(INSTALL_PATH)/
>
> I think you can squash patches #1 and #2 into a single "Fix make
> install target" patch.
>
> pw-bot: cr
>
> nit: This hardcodes the filename, and even though we only have one
> test that needs .BTF currently, you could add *.BTF to the loop:
>
> $(OUTPUT)/$$DIR/*.bpf.o $(OUTPUT)/$$DIR/*.BTF
>
> Then any future test that consumes a raw .BTF gets installed for free.

Good call! I'll prepare v2. Thanks for the review :)

>
>> @for DIR in $(TEST_INST_SUBDIRS); do \
>> mkdir -p $(INSTALL_PATH)/$$DIR; \
>> rsync -a $(if $(PERMISSIVE),--ignore-missing-args) \
>> - $(OUTPUT)/$$DIR/*.bpf.o \
>> + $(OUTPUT)/$$DIR/*.bpf.o $(OUTPUT)/$$DIR/resolve_btfids.test.o.BTF \
>> $(INSTALL_PATH)/$$DIR; \
>> done
>> endef
>>