Index: sys/arch/amd64/conf/GENERIC
===================================================================
RCS file: /cvsroot/src/sys/arch/amd64/conf/GENERIC,v
retrieving revision 1.529
diff -u -r1.529 GENERIC
--- sys/arch/amd64/conf/GENERIC	15 Jun 2019 06:40:34 -0000	1.529
+++ sys/arch/amd64/conf/GENERIC	17 Jun 2019 15:54:21 -0000
@@ -116,6 +116,7 @@
 #options 	KGDB_DEVNAME="\"com\"",KGDB_DEVADDR=0x3f8,KGDB_DEVRATE=9600
 makeoptions	DEBUG="-g"	# compile full symbol table for CTF
 #options	KUBSAN		# Kernel Undefined Behavior Sanitizer (kUBSan)
+#options	KUBSAN_PANIC	# (optional) Panic on all kUBSan reports
 #options 	SYSCALL_STATS	# per syscall counts
 #options 	SYSCALL_TIMES	# per syscall times
 #options 	SYSCALL_TIMES_HASCOUNTER	# use 'broken' rdtsc (soekris)
Index: common/lib/libc/misc/ubsan.c
===================================================================
RCS file: /cvsroot/src/common/lib/libc/misc/ubsan.c,v
retrieving revision 1.5
diff -u -r1.5 ubsan.c
--- common/lib/libc/misc/ubsan.c	13 Feb 2019 17:17:02 -0000	1.5
+++ common/lib/libc/misc/ubsan.c	17 Jun 2019 15:54:21 -0000
@@ -79,6 +79,12 @@
 #define CLR(t, f)	((t) &= ~(f))
 #endif
 
+#ifdef KUBSAN_PANIC
+static const bool alwaysFatal = true;
+#else
+static const bool alwaysFatal = false;
+#endif
+
 #define REINTERPRET_CAST(__dt, __st)	((__dt)(__st))
 #define STATIC_CAST(__dt, __st)		((__dt)(__st))
 
@@ -1122,7 +1128,7 @@
 
 	va_start(ap, pFormat);
 #if defined(_KERNEL)
-	if (isFatal)
+	if (isFatal || alwaysFatal)
 		vpanic(pFormat, ap);
 	else
 		vprintf(pFormat, ap);
@@ -1190,7 +1196,7 @@
 		ubsan_vsyslog(LOG_DEBUG | LOG_USER, &SyslogData, pFormat, tmp);
 		va_end(tmp);
 	}
-	if (isFatal || ISSET(ubsan_flags, UBSAN_ABORT)) {
+	if (isFatal || alwaysFatal || ISSET(ubsan_flags, UBSAN_ABORT)) {
 		abort();
 		__unreachable();
 		/* NOTREACHED */