From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D98EFC43331 for ; Thu, 2 Apr 2020 15:45:22 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id AE0E52063A for ; Thu, 2 Apr 2020 15:45:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AE0E52063A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=proxmox.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:43524 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jK21x-0004tP-RS for qemu-devel@archiver.kernel.org; Thu, 02 Apr 2020 11:45:21 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:54131) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jK21L-0004HM-Sk for qemu-devel@nongnu.org; Thu, 02 Apr 2020 11:44:44 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1jK21K-0003WQ-Rp for qemu-devel@nongnu.org; Thu, 02 Apr 2020 11:44:43 -0400 Received: from proxmox-new.maurer-it.com ([212.186.127.180]:28861) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1jK21H-0003Uz-W4; Thu, 02 Apr 2020 11:44:40 -0400 Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id EC0E445977; Thu, 2 Apr 2020 17:44:38 +0200 (CEST) Date: Thu, 2 Apr 2020 17:44:37 +0200 (CEST) From: Dietmar Maurer To: Kevin Wolf Message-ID: <1734893624.60.1585842277722@webmail.proxmox.com> In-Reply-To: <20200402142524.GD4006@linux.fritz.box> References: <713436887.61.1585668262838@webmail.proxmox.com> <20200331153719.GI7030@linux.fritz.box> <518198448.62.1585671498399@webmail.proxmox.com> <20200401103748.GA4680@linux.fritz.box> <997901084.0.1585755465486@webmail.proxmox.com> <20200401181256.GB27663@linux.fritz.box> <1403939459.52.1585765681569@webmail.proxmox.com> <20200401184431.GD27663@linux.fritz.box> <903538836.29.1585818619688@webmail.proxmox.com> <20200402121403.GB4006@linux.fritz.box> <20200402142524.GD4006@linux.fritz.box> Subject: Re: bdrv_drained_begin deadlock with io-threads MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Priority: 3 Importance: Normal X-Mailer: Open-Xchange Mailer v7.10.2-Rev23 X-Originating-Client: open-xchange-appsuite X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 212.186.127.180 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Dietmar Maurer Cc: Vladimir Sementsov-Ogievskiy , Stefan Hajnoczi , "qemu-devel@nongnu.org" , qemu-block@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" > It does looks more like your case because I now have bs.in_flight == 0 > and the BlockBackend of the scsi-hd device has in_flight == 8. yes, this looks very familiar. > Of course, this still doesn't answer why it happens, and I'm not sure if we > can tell without adding some debug code. > > I'm testing on my current block branch with Stefan's fixes on top. Note: I can trigger it with and without Stefans patches on top