[PATCH] kasan: remove hwasan-kernel-mem-intrinsic-prefix=1 for clang-14

From: Arnd Bergmann
Date: Fri Apr 14 2023 - 04:30:34 EST


From: Arnd Bergmann <arnd@xxxxxxxx>

Unknown -mllvm options don't cause an error to be returned by clang, so
the cc-option helper adds the unknown hwasan-kernel-mem-intrinsic-prefix=1
flag to CFLAGS with compilers that are new enough for hwasan but too
old for this option. This causes a rather unreadable build failure:

fixdep: error opening file: scripts/mod/.empty.o.d: No such file or directory
make[4]: *** [/home/arnd/arm-soc/scripts/Makefile.build:252: scripts/mod/empty.o] Error 2
fixdep: error opening file: scripts/mod/.devicetable-offsets.s.d: No such file or directory
make[4]: *** [/home/arnd/arm-soc/scripts/Makefile.build:114: scripts/mod/devicetable-offsets.s] Error 2

Add a version check to only allow this option with clang-15, gcc-13
or later versions.

Fixes: 51287dcb00cc ("kasan: emit different calls for instrumentable memintrinsics")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
There is probably a better way to do this than to add version checks,
but I could not figure it out.
---
scripts/Makefile.kasan | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/scripts/Makefile.kasan b/scripts/Makefile.kasan
index c186110ffa20..2cea0592e343 100644
--- a/scripts/Makefile.kasan
+++ b/scripts/Makefile.kasan
@@ -69,7 +69,12 @@ CFLAGS_KASAN := -fsanitize=kernel-hwaddress \
$(instrumentation_flags)

# Instrument memcpy/memset/memmove calls by using instrumented __hwasan_mem*().
+ifeq ($(call clang-min-version, 150000),y)
CFLAGS_KASAN += $(call cc-param,hwasan-kernel-mem-intrinsic-prefix=1)
+endif
+ifeq ($(call gcc-min-version, 130000),y)
+CFLAGS_KASAN += $(call cc-param,hwasan-kernel-mem-intrinsic-prefix=1)
+endif

endif # CONFIG_KASAN_SW_TAGS

--
2.39.2