kernel/linux.git/tools/lib/bpf/Makefile, branch v5.10.258

libbpf: Fix build issue with llvm-readelf

2022-04-13T19:00:56+00:00

[ Upstream commit 0908a66ad1124c1634c33847ac662106f7f2c198 ] There are cases where clang compiler is packaged in a way readelf is a symbolic link to llvm-readelf. In such cases, llvm-readelf will be used instead of default binutils readelf, and the following error will appear during libbpf build: # Warning: Num of global symbols in # /home/yhs/work/bpf-next/tools/testing/selftests/bpf/tools/build/libbpf/sharedobjs/libbpf-in.o (367) # does NOT match with num of versioned symbols in # /home/yhs/work/bpf-next/tools/testing/selftests/bpf/tools/build/libbpf/libbpf.so libbpf.map (383). # Please make sure all LIBBPF_API symbols are versioned in libbpf.map. # --- /home/yhs/work/bpf-next/tools/testing/selftests/bpf/tools/build/libbpf/libbpf_global_syms.tmp ... # +++ /home/yhs/work/bpf-next/tools/testing/selftests/bpf/tools/build/libbpf/libbpf_versioned_syms.tmp ... # @@ -324,6 +324,22 @@ # btf__str_by_offset # btf__type_by_id # btf__type_cnt # +LIBBPF_0.0.1 # +LIBBPF_0.0.2 # +LIBBPF_0.0.3 # +LIBBPF_0.0.4 # +LIBBPF_0.0.5 # +LIBBPF_0.0.6 # +LIBBPF_0.0.7 # +LIBBPF_0.0.8 # +LIBBPF_0.0.9 # +LIBBPF_0.1.0 # +LIBBPF_0.2.0 # +LIBBPF_0.3.0 # +LIBBPF_0.4.0 # +LIBBPF_0.5.0 # +LIBBPF_0.6.0 # +LIBBPF_0.7.0 # libbpf_attach_type_by_name # libbpf_find_kernel_btf # libbpf_find_vmlinux_btf_id # make[2]: *** [Makefile:184: check_abi] Error 1 # make[1]: *** [Makefile:140: all] Error 2 The above failure is due to different printouts for some ABS versioned symbols. For example, with the same libbpf.so, $ /bin/readelf --dyn-syms --wide tools/lib/bpf/libbpf.so | grep "LIBBPF" | grep ABS 134: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LIBBPF_0.5.0 202: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LIBBPF_0.6.0 ... $ /opt/llvm/bin/readelf --dyn-syms --wide tools/lib/bpf/libbpf.so | grep "LIBBPF" | grep ABS 134: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LIBBPF_0.5.0@@LIBBPF_0.5.0 202: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LIBBPF_0.6.0@@LIBBPF_0.6.0 ... The binutils readelf doesn't print out the symbol LIBBPF_* version and llvm-readelf does. Such a difference caused libbpf build failure with llvm-readelf. The proposed fix filters out all ABS symbols as they are not part of the comparison. This works for both binutils readelf and llvm-readelf. Reported-by: Delyan Kratunov Signed-off-by: Yonghong Song Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220204214355.502108-1-yhs@fb.com Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

libbpf: Re-build libbpf.so when libbpf.map changes

2021-09-15T07:50:40+00:00

[ Upstream commit 61c7aa5020e98ac2fdcf07d07eec1baf2e9f0a08 ] Ensure libbpf.so is re-built whenever libbpf.map is modified. Without this, changes to libbpf.map are not detected and versioned symbols mismatch error will be reported until `make clean && make` is used, which is a suboptimal developer experience. Fixes: 306b267cb3c4 ("libbpf: Verify versioned symbols") Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20210815070609.987780-8-andrii@kernel.org Signed-off-by: Sasha Levin

libbpf: Fix INSTALL flag order

2021-03-30T12:31:56+00:00

[ Upstream commit e7fb6465d4c8e767e39cbee72464e0060ab3d20c ] It was reported ([0]) that having optional -m flag between source and destination arguments in install command breaks bpftools cross-build on MacOS. Move -m to the front to fix this issue. [0] https://github.com/openwrt/openwrt/pull/3959 Fixes: 7110d80d53f4 ("libbpf: Makefile set specified permission mode") Signed-off-by: Georgi Valkov Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20210308183038.613432-1-andrii@kernel.org Signed-off-by: Sasha Levin

libbpf: Fix VERSIONED_SYM_COUNT number parsing

2020-11-19T16:45:12+00:00

We remove "other info" from "readelf -s --wide" output when parsing GLOBAL_SYM_COUNT variable, which was added in [1]. But we don't do that for VERSIONED_SYM_COUNT and it's failing the check_abi target on powerpc Fedora 33. The extra "other info" wasn't problem for VERSIONED_SYM_COUNT parsing until commit [2] added awk in the pipe, which assumes that the last column is symbol, but it can be "other info". Adding "other info" removal for VERSIONED_SYM_COUNT the same way as we did for GLOBAL_SYM_COUNT parsing. [1] aa915931ac3e ("libbpf: Fix readelf output parsing for Fedora") [2] 746f534a4809 ("tools/libbpf: Avoid counting local symbols in ABI check") Fixes: 746f534a4809 ("tools/libbpf: Avoid counting local symbols in ABI check") Signed-off-by: Jiri Olsa Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20201118211350.1493421-1-jolsa@kernel.org

libbpf: Compile in PIC mode only for shared library case

2020-09-30T00:05:31+00:00

Libbpf compiles .o's for static and shared library modes separately, so no need to specify -fPIC for both. Keep it only for shared library mode. Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Acked-by: Martin KaFai Lau Link: https://lore.kernel.org/bpf/20200929220604.833631-3-andriin@fb.com

libbpf: Compile libbpf under -O2 level by default and catch extra warnings

2020-09-30T00:05:31+00:00

For some reason compiler doesn't complain about uninitialized variable, fixed in previous patch, if libbpf is compiled without -O2 optimization level. So do compile it with -O2 and never let similar issue slip by again. -Wall is added unconditionally, so no need to specify it again. Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Acked-by: Martin KaFai Lau Link: https://lore.kernel.org/bpf/20200929220604.833631-2-andriin@fb.com

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2020-09-22T23:45:34+00:00

Two minor conflicts: 1) net/ipv4/route.c, adding a new local variable while moving another local variable and removing it's initial assignment. 2) drivers/net/dsa/microchip/ksz9477.c, overlapping changes. One pretty prints the port mode differently, whilst another changes the driver to try and obtain the port mode from the port node rather than the switch node. Signed-off-by: David S. Miller

tools/libbpf: Avoid counting local symbols in ABI check

2020-09-08T22:41:31+00:00

Encountered the following failure building libbpf from kernel 5.8.5 sources with GCC 8.4.0 and binutils 2.34: (long paths shortened) Warning: Num of global symbols in sharedobjs/libbpf-in.o (234) does NOT match with num of versioned symbols in libbpf.so (236). Please make sure all LIBBPF_API symbols are versioned in libbpf.map. --- libbpf_global_syms.tmp 2020-09-02 07:30:58.920084380 +0000 +++ libbpf_versioned_syms.tmp 2020-09-02 07:30:58.924084388 +0000 @@ -1,3 +1,5 @@ +_fini +_init bpf_btf_get_fd_by_id bpf_btf_get_next_id bpf_create_map make[4]: *** [Makefile:210: check_abi] Error 1 Investigation shows _fini and _init are actually local symbols counted amongst global ones: $ readelf --dyn-syms --wide libbpf.so|head -10 Symbol table '.dynsym' contains 343 entries: Num: Value Size Type Bind Vis Ndx Name 0: 00000000 0 NOTYPE LOCAL DEFAULT UND 1: 00004098 0 SECTION LOCAL DEFAULT 11 2: 00004098 8 FUNC LOCAL DEFAULT 11 _init@@LIBBPF_0.0.1 3: 00023040 8 FUNC LOCAL DEFAULT 14 _fini@@LIBBPF_0.0.1 4: 00000000 0 OBJECT GLOBAL DEFAULT ABS LIBBPF_0.0.4 5: 00000000 0 OBJECT GLOBAL DEFAULT ABS LIBBPF_0.0.1 6: 0000ffa4 8 FUNC GLOBAL DEFAULT 12 bpf_object__find_map_by_offset@@LIBBPF_0.0.1 A previous commit filtered global symbols in sharedobjs/libbpf-in.o. Do the same with the libbpf.so DSO for consistent comparison. Fixes: 306b267cb3c4 ("libbpf: Verify versioned symbols") Signed-off-by: Tony Ambardar Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200905214831.1565465-1-Tony.Ambardar@gmail.com

libbpf: Remove arch-specific include path in Makefile

2020-09-03T13:45:00+00:00

Ubuntu mainline builds for ppc64le are failing with the below error (*): CALL /home/kernel/COD/linux/scripts/atomic/check-atomics.sh DESCEND bpf/resolve_btfids Auto-detecting system features: ... libelf: [ [32mon[m ] ... zlib: [ [32mon[m ] ... bpf: [ [31mOFF[m ] BPF API too old make[6]: *** [Makefile:295: bpfdep] Error 1 make[5]: *** [Makefile:54: /home/kernel/COD/linux/debian/build/build-generic/tools/bpf/resolve_btfids//libbpf.a] Error 2 make[4]: *** [Makefile:71: bpf/resolve_btfids] Error 2 make[3]: *** [/home/kernel/COD/linux/Makefile:1890: tools/bpf/resolve_btfids] Error 2 make[2]: *** [/home/kernel/COD/linux/Makefile:335: __build_one_by_one] Error 2 make[2]: Leaving directory '/home/kernel/COD/linux/debian/build/build-generic' make[1]: *** [Makefile:185: __sub-make] Error 2 make[1]: Leaving directory '/home/kernel/COD/linux' resolve_btfids needs to be build as a host binary and it needs libbpf. However, libbpf Makefile hardcodes an include path utilizing $(ARCH). This results in mixing of cross-architecture headers resulting in a build failure. The specific header include path doesn't seem necessary for a libbpf build. Hence, remove the same. (*) https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.9-rc3/ppc64el/log Reported-by: Vaidyanathan Srinivasan Signed-off-by: Naveen N. Rao Signed-off-by: Daniel Borkmann Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200902084246.1513055-1-naveen.n.rao@linux.vnet.ibm.com

tools, bpf/build: Cleanup feature files on make clean

2020-08-28T12:04:27+00:00

The system for "Auto-detecting system features" located under tools/build/ are (currently) used by perf, libbpf and bpftool. It can contain stalled feature detection files, which are not cleaned up by libbpf and bpftool on make clean (side-note: perf tool is correct). Fix this by making the users invoke the make clean target. Some details about the changes. The libbpf Makefile already had a clean-config target (which seems to be copy-pasted from perf), but this target was not "connected" (a make dependency) to clean target. Choose not to rename target as someone might be using it. Did change the output from "CLEAN config" to "CLEAN feature-detect", to make it more clear what happens. This is related to the complaint and troubleshooting in the following link: https://lore.kernel.org/lkml/20200818122007.2d1cfe2d@carbon/ Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Daniel Borkmann Acked-by: Jiri Olsa Link: https://lore.kernel.org/lkml/20200818122007.2d1cfe2d@carbon/ Link: https://lore.kernel.org/bpf/159851841661.1072907.13770213104521805592.stgit@firesoul