From patchwork Tue Nov 14 17:24:14 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Max Reitz X-Patchwork-Id: 10057999 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 1D5306023A for ; Tue, 14 Nov 2017 17:37:37 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 068652980E for ; Tue, 14 Nov 2017 17:37:37 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id EF8822982F; Tue, 14 Nov 2017 17:37:36 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 79A6029817 for ; Tue, 14 Nov 2017 17:37:36 +0000 (UTC) Received: from localhost ([::1]:32829 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eEf9T-0000m2-MF for patchwork-qemu-devel@patchwork.kernel.org; Tue, 14 Nov 2017 12:37:35 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54252) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eEexc-0006rY-0j for qemu-devel@nongnu.org; Tue, 14 Nov 2017 12:25:26 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eEexX-0004jk-TI for qemu-devel@nongnu.org; Tue, 14 Nov 2017 12:25:19 -0500 Received: from mx1.redhat.com ([209.132.183.28]:42082) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eEexS-0004c6-En; Tue, 14 Nov 2017 12:25:10 -0500 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 9970181DE2; Tue, 14 Nov 2017 17:25:09 +0000 (UTC) Received: from localhost (unknown [10.40.205.72]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0F25D93539; Tue, 14 Nov 2017 17:25:08 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Date: Tue, 14 Nov 2017 18:24:14 +0100 Message-Id: <20171114172417.7654-18-mreitz@redhat.com> In-Reply-To: <20171114172417.7654-1-mreitz@redhat.com> References: <20171114172417.7654-1-mreitz@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Tue, 14 Nov 2017 17:25:09 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 17/20] block/vhdx.c: Don't blindly update the header X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Peter Maydell , Jeff Cody , qemu-devel@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Jeff Cody The VHDX specification requires that before user data modification of the vhdx image, the VHDX header file and data GUIDs need to be updated. In vhdx_open(), if the image is set to RDWR, we go ahead and update the header. However, just because the image is set to RDWR does not mean we can go ahead and write at this point - specifically, if the QEMU run state is INMIGRATE, the underlying file BS may be set to inactive via the BDS open flag of BDRV_O_INACTIVE. Attempting to write under this condition will cause an assert in bdrv_co_pwritev(). We can alternatively latch the first time the image is written. And lo and behold, we do just that, via vhdx_user_visible_write() in vhdx_co_writev(). This means the call to vhdx_update_headers() in vhdx_open() is likely just vestigial, and can be removed. Reported-by: Alexey Kardashevskiy Tested-by: Alexey Kardashevskiy Signed-off-by: Jeff Cody Message-id: 659e4cdba6ef4c651737852777c8c93d27b38040.1510059970.git.jcody@redhat.com Reviewed-by: Stefan Hajnoczi Reviewed-by: Denis V. Lunev Signed-off-by: Max Reitz --- block/vhdx.c | 7 ------- 1 file changed, 7 deletions(-) diff --git a/block/vhdx.c b/block/vhdx.c index 7ae4589879..9956933da6 100644 --- a/block/vhdx.c +++ b/block/vhdx.c @@ -1008,13 +1008,6 @@ static int vhdx_open(BlockDriverState *bs, QDict *options, int flags, goto fail; } - if (flags & BDRV_O_RDWR) { - ret = vhdx_update_headers(bs, s, false, NULL); - if (ret < 0) { - goto fail; - } - } - /* TODO: differencing files */ return 0;