x86/boot/compressed: Warn on orphan section placement

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@chromium.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20200902025347.2504702-6-keescook@chromium.org

diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index 5b7f6e175b03abd1a96008e1b998f97e7a128fba..871cc071c925d44e70d38bb92a7edc9d47dc5680 100644 (file)
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -54,6 +54,7 @@ KBUILD_LDFLAGS += $(call ld-option,--no-ld-generated-unwind-info)
 # Compressed kernel should be built as PIE since it may be loaded at any
 # address by the bootloader.
 LDFLAGS_vmlinux := -pie $(call ld-option, --no-dynamic-linker)
+LDFLAGS_vmlinux += $(call ld-option, --orphan-handling=warn)
 LDFLAGS_vmlinux += -T
 
 hostprogs      := mkpiggy