Thread (12 messages) 12 messages, 4 authors, 2020-09-08

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

From: Arvind Sankar <hidden>
Date: 2020-09-05 22:48:47
Also in: linux-arch, linux-efi, lkml

On Tue, Sep 01, 2020 at 07:53:46PM -0700, Kees Cook wrote:
quoted hunk ↗ jump to hunk
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 <redacted>
---
 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
With LLVM=1 and GCOV_KERNEL/GCOV_PROFILE_ALL enabled, there are
.eh_frame sections created. I see that KASAN and KCSAN currently discard
them. Does GCOV actually need them or should it also discard?

Thanks.

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help