block: Fix locking in qmp_block_resize()

The drain functions assume that we hold the AioContext lock of the drained block node. Make sure to actually take the lock. Cc: [email protected] Fixes: eb94b81 Signed-off-by: Kevin Wolf <[email protected]> Message-Id: <[email protected]> Reviewed-by: Vladimir Sementsov-Ogievskiy <[email protected]> Signed-off-by: Kevin Wolf <[email protected]>
dreddy · Dec 11, 2020 · 8089eab · 8089eab
1 parent d9dbf25
commit 8089eab
Showing 1 changed file with 4 additions and 1 deletion.
diff --git a/blockdev.c b/blockdev.c
@@ -2481,13 +2481,16 @@ void coroutine_fn qmp_block_resize(bool has_device, const char *device,
         return;
     }
 
+    bdrv_co_lock(bs);
     bdrv_drained_begin(bs);
+    bdrv_co_unlock(bs);
+
     old_ctx = bdrv_co_enter(bs);
     blk_truncate(blk, size, false, PREALLOC_MODE_OFF, 0, errp);
     bdrv_co_leave(bs, old_ctx);
-    bdrv_drained_end(bs);
 
     bdrv_co_lock(bs);
+    bdrv_drained_end(bs);
     blk_unref(blk);
     bdrv_co_unlock(bs);
 }