diff --git a/src/gallium/drivers/vc4/vc4_bufmgr.c b/src/gallium/drivers/vc4/vc4_bufmgr.c
index 7a366caf6a1..7c1195e3ff3 100644
--- a/src/gallium/drivers/vc4/vc4_bufmgr.c
+++ b/src/gallium/drivers/vc4/vc4_bufmgr.c
@@ -382,9 +382,11 @@ vc4_bo_open_handle(struct vc4_screen *screen,
 {
         struct vc4_bo *bo;
 
-        assert(size);
+        /* Note: the caller is responsible for locking screen->bo_handles_mutex.
+         * This allows the lock to cover the actual BO import, avoiding a race.
+         */
 
-        mtx_lock(&screen->bo_handles_mutex);
+        assert(size);
 
         bo = util_hash_table_get(screen->bo_handles, (void*)(uintptr_t)handle);
         if (bo) {
@@ -418,10 +420,14 @@ vc4_bo_open_name(struct vc4_screen *screen, uint32_t name)
         struct drm_gem_open o = {
                 .name = name
         };
+
+        mtx_lock(&screen->bo_handles_mutex);
+
         int ret = vc4_ioctl(screen->fd, DRM_IOCTL_GEM_OPEN, &o);
         if (ret) {
                 fprintf(stderr, "Failed to open bo %d: %s\n",
                         name, strerror(errno));
+                mtx_unlock(&screen->bo_handles_mutex);
                 return NULL;
         }
 
@@ -432,10 +438,14 @@ struct vc4_bo *
 vc4_bo_open_dmabuf(struct vc4_screen *screen, int fd)
 {
         uint32_t handle;
+
+        mtx_lock(&screen->bo_handles_mutex);
+
         int ret = drmPrimeFDToHandle(screen->fd, fd, &handle);
         int size;
         if (ret) {
                 fprintf(stderr, "Failed to get vc4 handle for dmabuf %d\n", fd);
+                mtx_unlock(&screen->bo_handles_mutex);
                 return NULL;
         }
 
@@ -443,6 +453,7 @@ vc4_bo_open_dmabuf(struct vc4_screen *screen, int fd)
         size = lseek(fd, 0, SEEK_END);
         if (size == -1) {
                 fprintf(stderr, "Couldn't get size of dmabuf fd %d.\n", fd);
+                mtx_unlock(&screen->bo_handles_mutex);
                 return NULL;
         }