powerpc/build: vdso linker warning for orphan sections

Add --orphan-handlin for vdsos, and adjust vdso linker scripts to deal
with orphan sections.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230609051002.3342-1-npiggin@gmail.com

arch/powerpc/kernel/vdso/Makefile

@@ -56,6 +56,8 @@ KCSAN_SANITIZE := n
 ccflags-y := -fno-common -fno-builtin
 ldflags-y := -Wl,--hash-style=both -nostdlib -shared -z noexecstack
 ldflags-$(CONFIG_LD_IS_LLD) += $(call cc-option,--ld-path=$(LD),-fuse-ld=lld)
+ldflags-$(CONFIG_LD_ORPHAN_WARN) += -Wl,--orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
+
 # Filter flags that clang will warn are unused for linking
 ldflags-y += $(filter-out $(CC_AUTO_VAR_INIT_ZERO_ENABLER) $(CC_FLAGS_FTRACE) -Wa$(comma)%, $(KBUILD_CFLAGS))
 

arch/powerpc/kernel/vdso/vdso32.lds.S

@@ -83,9 +83,11 @@ SECTIONS
 
 	/DISCARD/	: {
 		*(.note.GNU-stack)
+		*(*.EMB.apuinfo)
+		*(.branch_lt)
 		*(.data .data.* .gnu.linkonce.d.* .sdata*)
 		*(.bss .sbss .dynbss .dynsbss)
-		*(.got1)
+		*(.got1 .glink .iplt .rela*)
 	}
 }
 

arch/powerpc/kernel/vdso/vdso64.lds.S

@@ -32,7 +32,7 @@ SECTIONS
 	. = ALIGN(16);
 	.text		: {
 		*(.text .stub .text.* .gnu.linkonce.t.* __ftr_alt_*)
-		*(.sfpr .glink)
+		*(.sfpr)
 	}						:text
 	PROVIDE(__etext = .);
 	PROVIDE(_etext = .);
@@ -81,10 +81,12 @@ SECTIONS
 
 	/DISCARD/	: {
 		*(.note.GNU-stack)
+		*(*.EMB.apuinfo)
 		*(.branch_lt)
 		*(.data .data.* .gnu.linkonce.d.* .sdata*)
 		*(.bss .sbss .dynbss .dynsbss)
 		*(.opd)
+		*(.glink .iplt .plt .rela*)
 	}
 }