Hello,
On Sat, Dec 21, 2019 at 5:29 AM Andrii Nakryiko
<andrii.nakryiko@xxxxxxxxx> wrote:
>
> On Thu, Dec 19, 2019 at 7:26 PM Namhyung Kim <namhyung@xxxxxxxxxx> wrote:
> >
> > I got the following error when I tried to build perf on a read-only
> > filesystem with O=dir option.
> >
> > $ cd /some/where/ro/linux/tools/perf
> > $ make O=$HOME/build/perf
> > ...
> > CC /home/namhyung/build/perf/lib.o
> > /bin/sh: bpf_helper_defs.h: Read-only file system
> > make[3]: *** [Makefile:184: bpf_helper_defs.h] Error 1
> > make[2]: *** [Makefile.perf:778: /home/namhyung/build/perf/libbpf.a] Error 2
> > make[2]: *** Waiting for unfinished jobs....
> > LD /home/namhyung/build/perf/libperf-in.o
> > AR /home/namhyung/build/perf/libperf.a
> > PERF_VERSION = 5.4.0
> > make[1]: *** [Makefile.perf:225: sub-make] Error 2
> > make: *** [Makefile:70: all] Error 2
> >
> > It was becaused bpf_helper_defs.h was generated in current directory.
> > Move it to OUTPUT directory.
> >
> > Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
> > ---
>
> Overall nothing is obviously broken, except you need to fix up
> selftests/bpf's Makefile as well.
Thanks for pointing this out. It's because bpf selftest also needs the
bpf_helper_defs.h right? But I'm currently having a problem with LLVM
when building the selftests. Can you help me testing the patch below?
(It should be applied after this patch. Are you ok with it?)
>
> BTW, this patch doesn't apply cleanly to latest bpf-next, so please rebase.
>
> Also subject prefix should look like [PATCH bpf-next] if it's meant to
> be applied against bpf-next.
Will do.
Thanks
Namhyung
-----------8<-------------
diff --git a/tools/testing/selftests/bpf/Makefile
b/tools/testing/selftests/bpf/Makefile
index 866fc1cadd7c..897877f7849b 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -151,9 +151,9 @@ $(DEFAULT_BPFTOOL): force
$(BPFOBJ): force
$(MAKE) -C $(BPFDIR) OUTPUT=$(OUTPUT)/
-BPF_HELPERS := $(BPFDIR)/bpf_helper_defs.h $(wildcard $(BPFDIR)/bpf_*.h)
-$(BPFDIR)/bpf_helper_defs.h:
- $(MAKE) -C $(BPFDIR) OUTPUT=$(OUTPUT)/ bpf_helper_defs.h
+BPF_HELPERS := $(OUTPUT)/bpf_helper_defs.h $(wildcard $(BPFDIR)/bpf_*.h)
+$(OUTPUT)/bpf_helper_defs.h:
+ $(MAKE) -C $(BPFDIR) OUTPUT=$(OUTPUT)/ $(OUTPUT)/bpf_helper_defs.h
# Get Clang's default includes on this system, as opposed to those seen by
# '-target bpf'. This fixes "missing" files on some architectures/distros,
