diff --git a/vtest/vtest.h b/vtest/vtest.h
index dac716e..cc0f9c8 100644
--- a/vtest/vtest.h
+++ b/vtest/vtest.h
@@ -75,7 +75,7 @@ int vtest_buf_read(struct vtest_input *input, void *buf, int size);
 
 int vtest_resource_busy_wait(uint32_t length_dw);
 int vtest_resource_busy_wait_nop(uint32_t length_dw);
-int vtest_poll(void);
+void vtest_poll_resource_busy_wait(void);
 
 int vtest_ping_protocol_version(uint32_t length_dw);
 int vtest_protocol_version(uint32_t length_dw);
diff --git a/vtest/vtest_fuzzer.c b/vtest/vtest_fuzzer.c
index 4c3567a..89b12b2 100644
--- a/vtest/vtest_fuzzer.c
+++ b/vtest/vtest_fuzzer.c
@@ -119,11 +119,11 @@ static void vtest_fuzzer_run_renderer(int out_fd, struct vtest_input *input,
             break;
          }
          vtest_set_current_context(context);
-         vtest_poll();
+         vtest_poll_resource_busy_wait();
          continue;
       }
 
-      vtest_poll();
+      vtest_poll_resource_busy_wait();
       if (header[1] <= 0 || header[1] >= ARRAY_SIZE(vtest_commands)) {
          break;
       }
diff --git a/vtest/vtest_renderer.c b/vtest/vtest_renderer.c
index 9d56623..472fca6 100644
--- a/vtest/vtest_renderer.c
+++ b/vtest/vtest_renderer.c
@@ -80,8 +80,8 @@ struct vtest_renderer {
 
    uint32_t max_length;
 
-   int fence_id;
-   int last_fence;
+   int implicit_fence_submitted;
+   int implicit_fence_completed;
 
    struct list_head active_contexts;
    struct list_head free_contexts;
@@ -97,15 +97,15 @@ struct vtest_renderer {
  * VCMD_RESOURCE_BUSY_WAIT is used to wait GPU works (VCMD_SUBMIT_CMD) or CPU
  * works (VCMD_TRANSFER_GET2).  A fence is needed only for GPU works.
  */
-static void vtest_renderer_create_fence(struct vtest_renderer *renderer)
+static void vtest_create_implicit_fence(struct vtest_renderer *renderer)
 {
-   virgl_renderer_create_fence(renderer->fence_id++, 0);
+   virgl_renderer_create_fence(++renderer->implicit_fence_submitted, 0);
 }
 
-static void vtest_write_fence(UNUSED void *cookie, uint32_t fence_id_in)
+static void vtest_write_implicit_fence(UNUSED void *cookie, uint32_t fence_id_in)
 {
    struct vtest_renderer *renderer = (struct vtest_renderer*)cookie;
-   renderer->last_fence = fence_id_in;
+   renderer->implicit_fence_completed = fence_id_in;
 }
 
 static int vtest_get_drm_fd(void *cookie)
@@ -123,14 +123,13 @@ static int vtest_get_drm_fd(void *cookie)
 
 static struct virgl_renderer_callbacks renderer_cbs = {
    .version = 2,
-   .write_fence = vtest_write_fence,
+   .write_fence = vtest_write_implicit_fence,
    .get_drm_fd = vtest_get_drm_fd
 };
 
 
 static struct vtest_renderer renderer = {
    .max_length = UINT_MAX,
-   .fence_id = 1,
    .next_context_id = 1,
    .next_resource_id = 1,
 };
@@ -1072,7 +1071,7 @@ int vtest_submit_cmd(uint32_t length_dw)
    if (ret)
       return -1;
 
-   vtest_renderer_create_fence(&renderer);
+   vtest_create_implicit_fence(&renderer);
    return 0;
 }
 
@@ -1392,7 +1391,8 @@ int vtest_resource_busy_wait(UNUSED uint32_t length_dw)
    flags = bw_buf[VCMD_BUSY_WAIT_FLAGS];
 
    do {
-      busy = renderer.last_fence != (renderer.fence_id - 1);
+      busy = renderer.implicit_fence_completed !=
+             renderer.implicit_fence_submitted;
       if (!busy || !(flags & VCMD_BUSY_WAIT_FLAG_WAIT))
          break;
 
@@ -1445,10 +1445,10 @@ int vtest_resource_busy_wait_nop(UNUSED uint32_t length_dw)
    return 0;
 }
 
-int vtest_poll(void)
+void vtest_poll_resource_busy_wait(void)
 {
+   /* poll the implicit fences */
    virgl_renderer_poll();
-   return 0;
 }
 
 void vtest_set_max_length(uint32_t length)
diff --git a/vtest/vtest_server.c b/vtest/vtest_server.c
index f60ec11..198cba6 100644
--- a/vtest/vtest_server.c
+++ b/vtest/vtest_server.c
@@ -636,12 +636,12 @@ static int vtest_client_dispatch_commands(struct vtest_client *client)
          return VTEST_CLIENT_ERROR_CONTEXT_FAILED;
       }
       printf("%s: client context created.\n", __func__);
-      vtest_poll();
+      vtest_poll_resource_busy_wait();
 
       return 0;
    }
 
-   vtest_poll();
+   vtest_poll_resource_busy_wait();
    if (header[1] <= 0 || header[1] >= ARRAY_SIZE(vtest_commands)) {
       return VTEST_CLIENT_ERROR_COMMAND_ID;
    }