The linker script scripts/module.lds.S contains an unused DISCARD_EH_FRAME
definition introduced by commit 68c76ad4a957 ("arm64: unwind: add
asynchronous unwind tables to kernel and modules").
As shown in an earlier version of that patch [1], DISCARD_EH_FRAME was
meant to be used by SANITIZER_DISCARDS in the same file, as follows:
-# define SANITIZER_DISCARDS *(.eh_frame)
+# define SANITIZER_DISCARDS DISCARD_EH_FRAME
However, in the meantime, SANITIZER_DISCARDS was removed entirely from
module.lds.S by commit 89245600941e ("cfi: Switch to -fsanitize=kcfi").
Eventually, the mentioned commit 68c76ad4a957 only added the new
DISCARD_EH_FRAME definition to this file without actually using it.
The file include/asm-generic/vmlinux.lds.h contains a similar
DISCARD_EH_FRAME definition for vmlinux to discard .eh_frame sections that
may be present when CONFIG_GCOV_KERNEL, CONFIG_KASAN_GENERIC or
CONFIG_KCSAN is enabled. Testing these options on arm64 with LLVM 19.1 did
not show any unexpected .eh_frame sections in modules.
Remove the unused DISCARD_EH_FRAME definition from scripts/module.lds.S.
Link:
https://lore.kernel.org/linux-arm-kernel/[email protected]/
[1]
Signed-off-by: Petr Pavlu <[email protected]>
---
scripts/module.lds.S | 5 -----
1 file changed, 5 deletions(-)
diff --git a/scripts/module.lds.S b/scripts/module.lds.S
index b62683061d79..d0f200428957 100644
--- a/scripts/module.lds.S
+++ b/scripts/module.lds.S
@@ -3,11 +3,6 @@
* Archs are free to supply their own linker scripts. ld will
* combine them automatically.
*/
-#ifdef CONFIG_UNWIND_TABLES
-#define DISCARD_EH_FRAME
-#else
-#define DISCARD_EH_FRAME *(.eh_frame)
-#endif
#include <asm-generic/codetag.lds.h>
base-commit: 4549871118cf616eecdd2d939f78e3b9e1dddc48
--
2.54.0
