diff --git a/subprojects/libvhost-user/libvhost-user.c b/subprojects/libvhost-user/libvhost-user.c
index d67953a1c3..80f9952e71 100644
--- a/subprojects/libvhost-user/libvhost-user.c
+++ b/subprojects/libvhost-user/libvhost-user.c
@@ -651,7 +651,8 @@ generate_faults(VuDev *dev) {
 
         if (ioctl(dev->postcopy_ufd, UFFDIO_REGISTER, &reg_struct)) {
             vu_panic(dev, "%s: Failed to userfault region %d "
-                          "@%" PRIx64 " + size:%zx offset: %zx: (ufd=%d)%s\n",
+                          "@%" PRIx64 " + size:%" PRIx64 " offset: %" PRIx64
+                          ": (ufd=%d)%s\n",
                      __func__, i,
                      dev_region->mmap_addr,
                      dev_region->size, dev_region->mmap_offset,