Index: sys/amd64/conf/GENERIC
===================================================================
--- sys/amd64/conf/GENERIC	(revision 365390)
+++ sys/amd64/conf/GENERIC	(working copy)
@@ -108,7 +108,7 @@
 #options 	KCOV			# Kernel Coverage Sanitizer
 # Warning: KUBSAN can result in a kernel too large for loader to load
 #options 	KUBSAN			# Kernel Undefined Behavior Sanitizer
-#options 	KCSAN			# Kernel Concurrency Sanitizer
+options 	KCSAN			# Kernel Concurrency Sanitizer
 
 # Kernel dump features.
 options 	EKCD			# Support for encrypted kernel dumps
Index: sys/sys/cdefs.h
===================================================================
--- sys/sys/cdefs.h	(revision 365390)
+++ sys/sys/cdefs.h	(working copy)
@@ -880,8 +880,10 @@
  */
 #if __has_attribute(no_sanitize) && defined(__clang__)
 #define __nosanitizeaddress	__attribute__((no_sanitize("address")))
+#define __nosanitizethread	__attribute__((no_sanitize("thread")))
 #else
 #define __nosanitizeaddress
+#define __nosanitizethread
 #endif
 
 /* Guard variables and structure members by lock. */
Index: sys/x86/x86/local_apic.c
===================================================================
--- sys/x86/x86/local_apic.c	(revision 365390)
+++ sys/x86/x86/local_apic.c	(working copy)
@@ -215,7 +215,7 @@
 static void lapic_calibrate_initcount(struct lapic *la);
 static void lapic_calibrate_deadline(struct lapic *la);
 
-static uint32_t
+static uint32_t __nosanitizethread
 lapic_read32(enum LAPIC_REGISTERS reg)
 {
 	uint32_t res;
@@ -228,7 +228,7 @@
 	return (res);
 }
 
-static void
+static void __nosanitizethread
 lapic_write32(enum LAPIC_REGISTERS reg, uint32_t val)
 {
 
@@ -241,7 +241,7 @@
 	}
 }
 
-static void
+static void __nosanitizethread
 lapic_write32_nofence(enum LAPIC_REGISTERS reg, uint32_t val)
 {