Index: uspace/lib/c/generic/io/kio.c
===================================================================
--- uspace/lib/c/generic/io/kio.c	(revision 58daded42983dc7a64d6d8abca0485d5d85fe7a6)
+++ uspace/lib/c/generic/io/kio.c	(revision 0d83cf6f04f9a3bfef021c71a4d4e0c172f9ad79)
@@ -56,5 +56,6 @@
 errno_t kio_write(const void *buf, size_t size, size_t *nwritten)
 {
-	futex_lock(&kio_buffer.futex);
+	/* Using down/up instead of lock/unlock so we can print very early. */
+	futex_down(&kio_buffer.futex);
 
 	const char *s = buf;
@@ -82,5 +83,5 @@
 	}
 
-	futex_unlock(&kio_buffer.futex);
+	futex_up(&kio_buffer.futex);
 	if (nwritten)
 		*nwritten = size;