From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48632) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dmUCk-0001aI-8Y for qemu-devel@nongnu.org; Mon, 28 Aug 2017 20:16:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dmUCg-0005un-Uo for qemu-devel@nongnu.org; Mon, 28 Aug 2017 20:16:30 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:57765 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dmUCg-0005tX-O6 for qemu-devel@nongnu.org; Mon, 28 Aug 2017 20:16:26 -0400 Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v7T0E8F3099488 for ; Mon, 28 Aug 2017 20:16:26 -0400 Received: from e35.co.us.ibm.com (e35.co.us.ibm.com [32.97.110.153]) by mx0b-001b2d01.pphosted.com with ESMTP id 2cmr22ykgq-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 28 Aug 2017 20:16:26 -0400 Received: from localhost by e35.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 28 Aug 2017 18:16:25 -0600 From: Michael Roth Date: Mon, 28 Aug 2017 19:14:35 -0500 In-Reply-To: <1503965694-10794-1-git-send-email-mdroth@linux.vnet.ibm.com> References: <1503965694-10794-1-git-send-email-mdroth@linux.vnet.ibm.com> Message-Id: <1503965694-10794-61-git-send-email-mdroth@linux.vnet.ibm.com> Subject: [Qemu-devel] [PATCH 60/79] commit: Fix completion with extra reference List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, Kevin Wolf From: Kevin Wolf commit_complete() can't assume that after its block_job_completed() the job is actually immediately freed; someone else may still be holding references. In this case, the op blockers on the intermediate nodes make the graph reconfiguration in the completion code fail. Call block_job_remove_all_bdrv() manually so that we know for sure that any blockers on intermediate nodes are given up. Cc: qemu-stable@nongnu.org Signed-off-by: Kevin Wolf Reviewed-by: Eric Blake Reviewed-by: Max Reitz (cherry picked from commit 4f78a16fee462471416dc49b409d57b2071cf3d9) Signed-off-by: Michael Roth --- block/commit.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/block/commit.c b/block/commit.c index 3bae46e..fba25e2 100644 --- a/block/commit.c +++ b/block/commit.c @@ -119,6 +119,13 @@ static void commit_complete(BlockJob *job, void *opaque) } g_free(s->backing_file_str); blk_unref(s->top); + + /* If there is more than one reference to the job (e.g. if called from + * block_job_finish_sync()), block_job_completed() won't free it and + * therefore the blockers on the intermediate nodes remain. This would + * cause bdrv_set_backing_hd() to fail. */ + block_job_remove_all_bdrv(job); + block_job_completed(&s->common, ret); g_free(data); -- 2.7.4