[PATCH v7 4/5] x86/build: Warn on orphan section placement

From: Kees Cook
Date: Tue Sep 01 2020 - 22:54:24 EST


We don't want to depend on the linker's orphan section placement
heuristics as these can vary between linkers, and may change between
versions. All sections need to be explicitly handled in the linker script.

Now that all sections are explicitly handled, enable orphan section
warnings.

Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
arch/x86/Makefile | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index 4346ffb2e39f..154259f18b8b 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -209,6 +209,10 @@ ifdef CONFIG_X86_64
LDFLAGS_vmlinux += -z max-page-size=0x200000
endif

+# We never want expected sections to be placed heuristically by the
+# linker. All sections should be explicitly named in the linker script.
+LDFLAGS_vmlinux += $(call ld-option, --orphan-handling=warn)
+
archscripts: scripts_basic
$(Q)$(MAKE) $(build)=arch/x86/tools relocs

--
2.25.1