From: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
This is _not_ an upstream commit and just for 4.19.y only. It is based
on commit 32ef9e5054ec0321b9336058c58ec749e9c6b0fe upstream.
Alexey reported that the fraction of unknown filename instances in
kallsyms grew from ~0.3% to ~10% recently; Bill and Greg tracked it down
to assembler defined symbols, which regressed as a result of:
commit b8a9092330da ("Kbuild: do not emit debug info for assembly with LLVM_IAS=1")
In that commit, I allude to restoring debug info for assembler defined
symbols in a follow up patch, but it seems I forgot to do so in
commit a66049e2cf0e ("Kbuild: make DWARF version a choice")
Fixes: b8a9092330da ("Kbuild: do not emit debug info for assembly with LLVM_IAS=1")
Signed-off-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
Makefile | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/Makefile
+++ b/Makefile
@@ -744,7 +744,9 @@ KBUILD_CFLAGS += $(call cc-option, -gs
else
KBUILD_CFLAGS += -g
endif
-ifneq ($(LLVM_IAS),1)
+ifeq ($(LLVM_IAS),1)
+KBUILD_AFLAGS += -g
+else
KBUILD_AFLAGS += -Wa,-gdwarf-2
endif
endif
