Nicholas Piggin [off-list ref] writes:

On Mon, 28 Nov 2016 22:07:39 +1100
Michael Ellerman [off-list ref] wrote:

quoted

Nicholas Piggin [off-list ref] writes:

quoted

diff --git a/arch/powerpc/boot/wrapper b/arch/powerpc/boot/wrapper
index 404b3aa..cd941a8 100755
--- a/arch/powerpc/boot/wrapper
+++ b/arch/powerpc/boot/wrapper

@@ -181,6 +181,13 @@ case "$elfformat" in
     elf32-powerpc)	format=elf32ppc	;;
 esac
 
+# Do not include PT_INTERP segment when linking pie. Non-pie linking
+# just ignores this option.
+LD_VERSION=$(${CROSS}ld --version | $srctree/scripts/ld-version.sh)
+LD_NO_DL_MIN_VERSION=$(echo 2.26 | $srctree/scripts/ld-version.sh)
+if [ "$LD_VERSION" -ge "$LD_NO_DL_MIN_VERSION" ] ; then
+	nodl="--no-dynamic-linker"
+fi  

Some distros (RHEL at least?), ship the wrapper as a standalone script.
So I don't think we can call things in $srctree. Or at least I don't
know how that's supposed to work when it's shipped standalone.
We're also basically reinventing ld-option, which is a PITA.

Okay I didn't realize that. It's already using mkuboot.sh, but only
for uboot targets... I don't know, I don't have any good ideas at the
moment.

That looks like a bug, but I guess no one runs Fedora/RHEL on those
machines? Previously it just called mkimage using $PATH.

The Fedora spec file does:

make DESTDIR=$RPM_BUILD_ROOT bootwrapper_install WRAPPER_OBJDIR=%{_libdir}/kernel-wrapper WRAPPER_DTSDIR=%{_libdir}/kernel-wrapper/dts

bootwrapper_install installs a bunch of files, and also calls:

quiet_cmd_install_wrapper = INSTALL $(patsubst $(DESTDIR)$(WRAPPER_BINDIR)/%,%,$@)
      cmd_install_wrapper = $(INSTALL)  -m0755 $(patsubst $(DESTDIR)$(WRAPPER_BINDIR)/%,$(srctree)/$(obj)/%,$@) $@ ;\
				sed -i $@ -e 's%^object=.*%object=$(WRAPPER_OBJDIR)%' \
					  -e 's%^objbin=.*%objbin=$(WRAPPER_BINDIR)%' \

ie. it seds the script. So we could probably just install ld-version.sh
into $(DESTDIR)$(WRAPPER_OBJDIR) and then sed $srctree maybe?

But it's old code and I'm not that across how it gets used in the wild.
CC'ing Gustavo who is our Fedora/RHEL/Power guy.

cheers