The function stream_prepare() calls bdrv_drain_all_begin(), which
must be called with the graph unlocked.

Also mark the JobDriver's prepare() callback as GRAPH_UNLOCKED_PTR,
because that is the callback via which stream_prepare() is reached.

Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
---
 block/stream.c     | 2 +-
 include/qemu/job.h | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/block/stream.c b/block/stream.c
index 17e240460c..c0616b69e2 100644
--- a/block/stream.c
+++ b/block/stream.c
@@ -51,7 +51,7 @@ static int coroutine_fn stream_populate(BlockBackend *blk,
     return blk_co_preadv(blk, offset, bytes, NULL, BDRV_REQ_PREFETCH);
 }
 
-static int stream_prepare(Job *job)
+static int GRAPH_UNLOCKED stream_prepare(Job *job)
 {
     StreamBlockJob *s = container_of(job, StreamBlockJob, common.job);
     BlockDriverState *unfiltered_bs;
diff --git a/include/qemu/job.h b/include/qemu/job.h
index a5a04155ea..bb8ee766ef 100644
--- a/include/qemu/job.h
+++ b/include/qemu/job.h
@@ -263,7 +263,7 @@ struct JobDriver {
      * This callback will not be invoked if the job has already failed.
      * If it fails, abort and then clean will be called.
      */
-    int (*prepare)(Job *job);
+    int GRAPH_UNLOCKED_PTR (*prepare)(Job *job);
 
     /**
      * If the callback is not NULL, it will be invoked when all the jobs
-- 
2.39.5