[Unstable] libbpf: Fix readelf output parsing on powerpc with recent binutils
diff mbox series

Message ID 20191203170934.82741-1-cascardo@canonical.com
State New
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Series
  • [Unstable] libbpf: Fix readelf output parsing on powerpc with recent binutils
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Commit Message

Thadeu Lima de Souza Cascardo Dec. 3, 2019, 5:09 p.m. UTC
From: Aurelien Jarno <aurelien@aurel32.net>

BugLink: https://bugs.launchpad.net/bugs/1854974

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: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
---
 tools/lib/bpf/Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Thadeu Lima de Souza Cascardo Dec. 3, 2019, 5:11 p.m. UTC | #1
On Tue, Dec 03, 2019 at 02:09:34PM -0300, Thadeu Lima de Souza Cascardo wrote:
> From: Aurelien Jarno <aurelien@aurel32.net>
> 
> BugLink: https://bugs.launchpad.net/bugs/1854974
> 
> 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

(cherry picked from commit 3464afdf11f9a1e031e7858a05351ceca1792fea linux-next)

> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
> ---
>  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 56ce6292071b..a7d7d35885c7 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 $(OUTPUT)libbpf-in.o |		 \
>  		    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
> 
> 
> -- 
> kernel-team mailing list
> kernel-team@lists.ubuntu.com
> https://lists.ubuntu.com/mailman/listinfo/kernel-team
Seth Forshee Dec. 6, 2019, 4:40 a.m. UTC | #2
On Tue, Dec 03, 2019 at 02:09:34PM -0300, Thadeu Lima de Souza Cascardo wrote:
> From: Aurelien Jarno <aurelien@aurel32.net>
> 
> BugLink: https://bugs.launchpad.net/bugs/1854974
> 
> 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: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>

Applied to unstable/master, thanks!

Patch
diff mbox series

diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
index 56ce6292071b..a7d7d35885c7 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 $(OUTPUT)libbpf-in.o |		 \
 		    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 |		 \