block: avoid potential deadlock during bdrv_graph_wrlock() in bdrv_close()

by passing the BlockDriverState along, so the held AioContext can be
dropped before polling. See commit 31b2ddfea3 ("graph-lock: Unlock the
AioContext while polling") which introduced this functionality for
more information.

The only way to reach bdrv_close() is via bdrv_unref() and for calling
that the BlockDriverState's AioContext lock is supposed to be held.

Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Message-ID: <20231019131936.414246-3-f.ebner@proxmox.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Fiona Ebner 2023-10-19 15:19:35 +02:00 committed by Kevin Wolf
parent 67446e605d
commit e462c6d27d

View File

@ -5200,7 +5200,7 @@ static void bdrv_close(BlockDriverState *bs)
bs->drv = NULL;
}
bdrv_graph_wrlock(NULL);
bdrv_graph_wrlock(bs);
QLIST_FOREACH_SAFE(child, &bs->children, next, next) {
bdrv_unref_child(bs, child);
}