diff --git a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_subr.c b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_subr.c
--- a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_subr.c
+++ b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_subr.c
@@ -694,7 +694,6 @@
 
 	va_copy(ap2, ap);
 	n = vfprintf(fp, format, ap2);
-	fflush(fp);
 	va_end(ap2);
 	va_end(ap);