libbpf: Fix readelf output parsing on powerpc with recent binutils

On powerpc with recent versions of binutils, readelf outputs an extra
field when dumping the symbols of an object file. For example:

    35: 0000000000000838    96 FUNC    LOCAL  DEFAULT [<localentry>: 8]     1 btf_is_struct

The extra "[<localentry>: 8]" prevents the GLOBAL_SYM_COUNT variable to
be computed correctly and causes the check_abi target to fail.

Fix that by looking for the symbol name in the last field instead of the
8th one. This way it should also cope with future extra fields.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/bpf/20191201195728.4161537-1-aurelien@aurel32.net
This commit is contained in:
Aurelien Jarno 2019-12-01 20:57:28 +01:00 committed by Daniel Borkmann
parent e1608f3fa8
commit 3464afdf11

View File

@ -147,7 +147,7 @@ TAGS_PROG := $(if $(shell which etags 2>/dev/null),etags,ctags)
GLOBAL_SYM_COUNT = $(shell readelf -s --wide $(BPF_IN_SHARED) | \
cut -d "@" -f1 | sed 's/_v[0-9]_[0-9]_[0-9].*//' | \
awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$8}' | \
awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}' | \
sort -u | wc -l)
VERSIONED_SYM_COUNT = $(shell readelf -s --wide $(OUTPUT)libbpf.so | \
grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | sort -u | wc -l)
@ -216,7 +216,7 @@ check_abi: $(OUTPUT)libbpf.so
"versioned in $(VERSION_SCRIPT)." >&2; \
readelf -s --wide $(BPF_IN_SHARED) | \
cut -d "@" -f1 | sed 's/_v[0-9]_[0-9]_[0-9].*//' | \
awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$8}'| \
awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}'| \
sort -u > $(OUTPUT)libbpf_global_syms.tmp; \
readelf -s --wide $(OUTPUT)libbpf.so | \
grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | \