[PATCH] powerpc: suppress some linker warnings in recent linker versions

[PATCH] powerpc: suppress some linker warnings in recent linker versions

[Stephen Rothwell]

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This is a follow on from commit

  0d362be5b142 ("Makefile: link with -z noexecstack --no-warn-rwx-segments")

for arch/powerpc/boot to address wanrings like:

  ld: warning: opal-calls.o: missing .note.GNU-stack section implies executable stack
  ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker
  ld: warning: arch/powerpc/boot/zImage.epapr has a LOAD segment with RWX permissions

This fixes issue https://github.com/linuxppc/issues/issues/417

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
---
 arch/powerpc/boot/wrapper | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

I have only done a positive test on this i.e. I have binutils v2.39
installed.

diff --git a/arch/powerpc/boot/wrapper b/arch/powerpc/boot/wrapper
index 55978f32fa77..d78c34bd5d41 100755
--- a/arch/powerpc/boot/wrapper
+++ b/arch/powerpc/boot/wrapper
@@ -215,6 +215,11 @@ ld_version()
     }'
 }
 
+ld_is_lld()
+{
+	${CROSS}ld -V 2>&1 | grep -q LLD
+}
+
 # Do not include PT_INTERP segment when linking pie. Non-pie linking
 # just ignores this option.
 LD_VERSION=$(${CROSS}ld --version | ld_version)
@@ -223,6 +228,14 @@ if [ "$LD_VERSION" -ge "$LD_NO_DL_MIN_VERSION" ] ; then
 	nodl="--no-dynamic-linker"
 fi
 
+# suppress some warnings in recent ld versions
+nowarn="-z noexecstack"
+if ! ld_is_lld; then
+	if [ "$LD_VERSION" -ge "$(echo 2.39 | ld_version)" ]; then
+		nowarn="$nowarn --no-warn-rwx-segments"
+	fi
+fi
+
 platformo=$object/"$platform".o
 lds=$object/zImage.lds
 ext=strip
@@ -504,7 +517,7 @@ if [ "$platform" != "miboot" ]; then
         text_start="-Ttext $link_address"
     fi
 #link everything
-    ${CROSS}ld -m $format -T $lds $text_start $pie $nodl $rodynamic $notext -o "$ofile" $map \
+    ${CROSS}ld -m $format -T $lds $text_start $pie $nodl $nowarn $rodynamic $notext -o "$ofile" $map \
 	$platformo $tmp $object/wrapper.a
     rm $tmp
 fi
-- 
2.35.1

-- 
Cheers,
Stephen Rothwell

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Re: [PATCH] powerpc: suppress some linker warnings in recent linker versions

[Michael Ellerman]

On Mon, 10 Oct 2022 16:57:21 +1100, Stephen Rothwell wrote:
> This is a follow on from commit
> 
>   0d362be5b142 ("Makefile: link with -z noexecstack --no-warn-rwx-segments")
> 
> for arch/powerpc/boot to address wanrings like:
> 
>   ld: warning: opal-calls.o: missing .note.GNU-stack section implies executable stack
>   ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker
>   ld: warning: arch/powerpc/boot/zImage.epapr has a LOAD segment with RWX permissions
> 
> [...]

Applied to powerpc/next.

[1/1] powerpc: suppress some linker warnings in recent linker versions
      https://git.kernel.org/powerpc/c/579aee9fc594af94c242068c011b0233563d4bbf

cheers