leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

bpftool: Fix bootstrapping during a cross compilation

Browse Source 
This change adjusts the Makefile to use "HOSTAR" as the archive tool
to keep the sanity of the build process for the bootstrap part in
check. For the rationale, please continue reading.

When cross compiling bpftool with buildroot, it leads to an invocation
like:

$ AR="/path/to/buildroot/host/bin/arc-linux-gcc-ar" \
  CC="/path/to/buildroot/host/bin/arc-linux-gcc"    \
  ...
  make

Which in return fails while building the bootstrap section:

----------------------------------8<----------------------------------

  make: Entering directory '/src/bpftool-v6.7.0/src'
  ...                        libbfd: [ on  ]
  ...        disassembler-four-args: [ on  ]
  ...                          zlib: [ on  ]
  ...                        libcap: [ OFF ]
  ...               clang-bpf-co-re: [ on  ] <-- triggers bootstrap

  .
  .
  .

    LINK     /src/bpftool-v6.7.0/src/bootstrap/bpftool
  /usr/bin/ld: /src/bpftool-v6.7.0/src/bootstrap/libbpf/libbpf.a:
               error adding symbols: archive has no index; run ranlib
               to add one
  collect2: error: ld returned 1 exit status
  make: *** [Makefile:211: /src/bpftool-v6.7.0/src/bootstrap/bpftool]
            Error 1
  make: *** Waiting for unfinished jobs....
    AR       /src/bpftool-v6.7.0/src/libbpf/libbpf.a
    make[1]: Leaving directory '/src/bpftool-v6.7.0/libbpf/src'
    make: Leaving directory '/src/bpftool-v6.7.0/src'

---------------------------------->8----------------------------------

This occurs because setting "AR" confuses the build process for the
bootstrap section and it calls "arc-linux-gcc-ar" to create and index
"libbpf.a" instead of the host "ar".

Signed-off-by: Shahab Vahedi <shahab@synopsys.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Cc: Jean-Philippe Brucker <jean-philippe@linaro.org>
Link: https://lore.kernel.org/bpf/8d297f0c-cfd0-ef6f-3970-6dddb3d9a87a@synopsys.com
This commit is contained in:
Shahab Vahedi 2022-06-08 14:29:28 +00:00 committed by Daniel Borkmann
parent d352bd889b
commit 0b817059a8
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
tools/bpf/bpftool/Makefile
View File

@ -53,7 +53,7 @@ $(LIBBPF_INTERNAL_HDRS): $(LIBBPF_HDRS_DIR)/%.h: $(BPF_DIR)/%.h | $(LIBBPF_HDRS_
$(LIBBPF_BOOTSTRAP): $(wildcard $(BPF_DIR)/*.[ch] $(BPF_DIR)/Makefile) | $(LIBBPF_BOOTSTRAP_OUTPUT) $(LIBBPF_BOOTSTRAP): $(wildcard $(BPF_DIR)/*.[ch] $(BPF_DIR)/Makefile) | $(LIBBPF_BOOTSTRAP_OUTPUT)
$(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(LIBBPF_BOOTSTRAP_OUTPUT) \ $(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(LIBBPF_BOOTSTRAP_OUTPUT) \
DESTDIR=$(LIBBPF_BOOTSTRAP_DESTDIR:/=) prefix= \ DESTDIR=$(LIBBPF_BOOTSTRAP_DESTDIR:/=) prefix= \
ARCH= CROSS_COMPILE= CC=$(HOSTCC) LD=$(HOSTLD) $@ install_headers ARCH= CROSS_COMPILE= CC=$(HOSTCC) LD=$(HOSTLD) AR=$(HOSTAR) $@ install_headers
$(LIBBPF_BOOTSTRAP_INTERNAL_HDRS): $(LIBBPF_BOOTSTRAP_HDRS_DIR)/%.h: $(BPF_DIR)/%.h | $(LIBBPF_BOOTSTRAP_HDRS_DIR) $(LIBBPF_BOOTSTRAP_INTERNAL_HDRS): $(LIBBPF_BOOTSTRAP_HDRS_DIR)/%.h: $(BPF_DIR)/%.h | $(LIBBPF_BOOTSTRAP_HDRS_DIR)
$(call QUIET_INSTALL, $@) $(call QUIET_INSTALL, $@)