From dc62da88b5d17477227a3563a6ad466129d416d6 Mon Sep 17 00:00:00 2001
From: "Denis V. Lunev" <den@openvz.org>
Date: Mon, 27 Mar 2017 17:38:08 +0300
Subject: [PATCH] parallels: wrong call to bdrv_truncate

Parallels driver should not call bdrv_truncate if the image was opened
in the read-only mode. Without the patch
    qemu-img check harddisk.hds
asserts with
    bdrv_truncate: Assertion `child->perm & BLK_PERM_RESIZE' failed.

Parameters used on the write path are not needed if the image is opened
in the read-only mode.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reported-by: Edgar Kaziahmedov <edos@virtuozzo.mipt.ru>
Message-id: 1490625488-7980-1-git-send-email-den@openvz.org
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block/parallels.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/block/parallels.c b/block/parallels.c
index 6bf93753e8..4173b3fb9d 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -687,7 +687,8 @@ static int parallels_open(BlockDriverState *bs, QDict *options, int flags,
     if (local_err != NULL) {
         goto fail_options;
     }
-    if (!bdrv_has_zero_init(bs->file->bs) ||
+
+    if (!(flags & BDRV_O_RESIZE) || !bdrv_has_zero_init(bs->file->bs) ||
             bdrv_truncate(bs->file, bdrv_getlength(bs->file->bs)) != 0) {
         s->prealloc_mode = PRL_PREALLOC_MODE_FALLOCATE;
     }
-- 
2.30.2