Re: [PATCH] libbpf: Fix build on read-only filesystems
From: Andrii Nakryiko
Date: Fri Dec 20 2019 - 15:29:50 EST
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.
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.
> tools/lib/bpf/Makefile | 14 +++++++-------
> 1 file changed, 7 insertions(+), 7 deletions(-)
>
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