The LLVM compiler uses hwasan-instrument-with-calls parameter to setup inline or outline mode in tag-based KASAN. If zeroed, it means the instrumentation implementation will be pasted into each relevant location along with KASAN related constants during compilation. If set to one all function instrumentation will be done with function calls instead. The default hwasan-instrument-with-calls value for the x86 architecture in the compiler is "1", which is not true for other architectures. Because of this, enabling inline mode in software tag-based KASAN doesn't work on x86 as the kernel script doesn't zero out the parameter and always sets up the outline mode. Explicitly zero out hwasan-instrument-with-calls when enabling inline mode in tag-based KASAN. Signed-off-by: Maciej Wieczor-Retman --- Changelog v3: - Add this patch to the series. scripts/Makefile.kasan | 3 +++ 1 file changed, 3 insertions(+) diff --git a/scripts/Makefile.kasan b/scripts/Makefile.kasan index 693dbbebebba..2c7be96727ac 100644 --- a/scripts/Makefile.kasan +++ b/scripts/Makefile.kasan @@ -76,8 +76,11 @@ CFLAGS_KASAN := -fsanitize=kernel-hwaddress RUSTFLAGS_KASAN := -Zsanitizer=kernel-hwaddress \ -Zsanitizer-recover=kernel-hwaddress +# LLVM sets hwasan-instrument-with-calls to 1 on x86 by default. Set it to 0 +# when inline mode is enabled. ifdef CONFIG_KASAN_INLINE kasan_params += hwasan-mapping-offset=$(KASAN_SHADOW_OFFSET) + kasan_params += hwasan-instrument-with-calls=0 else kasan_params += hwasan-instrument-with-calls=1 endif -- 2.50.1