kvm: Fix stack access mode in KVM test ELF headers

When the linker converts guest payload binary into a linkable resource
object file, it somehow defaults to requesting executable stack section
for the final test binary. This trips some build-time security checks
on newer systems. Add explicit linker option to make the stack
non-executable.

Suggested-by: Fabian Vogt <fvogt@suse.com>
Signed-off-by: Martin Doucha <mdoucha@suse.cz>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Reviewed-by: Cyril Hrubis <chrubis@suse.cz>

testcases/kernel/kvm/Makefile

@@ -50,11 +50,11 @@ include $(top_srcdir)/include/mk/generic_leaf_target.mk
 ifdef VERBOSE
 	$(CC) $(GUEST_CPPFLAGS) $(GUEST_CFLAGS) $(GUEST_LDFLAGS) -o $*-payload.elf $^ $(GUEST_LDLIBS)
 	objcopy -O binary -j .init.boot -j .text -j .data -j .init -j .preinit_array -j .init_array --gap-fill=0 $*-payload.elf $*-payload.bin
-	ld -r -T $(abs_srcdir)/linker/payload.lds --oformat=$(BIN_FORMAT) -o $@ $*-payload.bin
+	ld -z noexecstack -r -T $(abs_srcdir)/linker/payload.lds --oformat=$(BIN_FORMAT) -o $@ $*-payload.bin
 else
 	@$(CC) $(GUEST_CPPFLAGS) $(GUEST_CFLAGS) $(GUEST_LDFLAGS) -o $*-payload.elf $^ $(GUEST_LDLIBS)
 	@objcopy -O binary -j .init.boot -j .text -j .data -j .init -j .preinit_array -j .init_array --gap-fill=0 $*-payload.elf $*-payload.bin
-	@ld -r -T $(abs_srcdir)/linker/payload.lds --oformat=$(BIN_FORMAT) -o $@ $*-payload.bin
+	@ld -z noexecstack -r -T $(abs_srcdir)/linker/payload.lds --oformat=$(BIN_FORMAT) -o $@ $*-payload.bin
 	@echo KVM_CC $(target_rel_dir)$@
 endif
 	@rm $*-payload.elf $*-payload.bin