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From:   Sasha Levin <sashal@kernel.org>
To:     linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc:     Aurelien Jarno <aurelien@aurel32.net>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Sasha Levin <sashal@kernel.org>, netdev@vger.kernel.org,
        bpf@vger.kernel.org
Subject: [PATCH AUTOSEL 5.4 66/78] libbpf: Fix readelf output parsing on powerpc with recent binutils
Date:   Sat, 18 Apr 2020 10:40:35 -0400
Message-Id: <20200418144047.9013-66-sashal@kernel.org>
In-Reply-To: <20200418144047.9013-1-sashal@kernel.org>
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From: Aurelien Jarno <aurelien@aurel32.net>

[ Upstream commit 3464afdf11f9a1e031e7858a05351ceca1792fea ]

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
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/lib/bpf/Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
index 33e2638ef7f0d..122321d549227 100644
--- a/tools/lib/bpf/Makefile
+++ b/tools/lib/bpf/Makefile
@@ -145,7 +145,7 @@ PC_FILE		:= $(addprefix $(OUTPUT),$(PC_FILE))
 
 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)
@@ -217,7 +217,7 @@ 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 |		 \
-- 
2.20.1