diff --git a/sys/conf/kern.pre.mk b/sys/conf/kern.pre.mk
--- a/sys/conf/kern.pre.mk
+++ b/sys/conf/kern.pre.mk
@@ -92,6 +92,16 @@
 # XXX LOCORE means "don't declare C stuff" not "for locore.s".
 ASM_CFLAGS= -x assembler-with-cpp -DLOCORE ${CFLAGS} ${ASM_CFLAGS.${.IMPSRC:T}} 
 
+KASAN_ENABLED!=	grep KASAN opt_global.h || true ; echo
+.if !empty(KASAN_ENABLED)
+SAN_CFLAGS+=	-fsanitize=kernel-address \
+		-mllvm -asan-stack=true \
+		-mllvm -asan-instrument-dynamic-allocas=true \
+		-mllvm -asan-globals=true \
+		-mllvm -asan-use-after-scope=true \
+		-mllvm -asan-instrumentation-with-call-threshold=0
+.endif
+
 KCSAN_ENABLED!=	grep KCSAN opt_global.h || true ; echo
 .if !empty(KCSAN_ENABLED)
 SAN_CFLAGS+=	-fsanitize=thread
diff --git a/sys/conf/options b/sys/conf/options
--- a/sys/conf/options
+++ b/sys/conf/options
@@ -229,6 +229,7 @@
 
 # Sanitizers
 COVERAGE	opt_global.h
+KASAN		opt_global.h
 KCOV
 KCSAN		opt_global.h
 KUBSAN		opt_global.h