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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 D10C5C49ED6 for ; Wed, 11 Sep 2019 22:06:33 +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 A230F2054F for ; Wed, 11 Sep 2019 22:06:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A230F2054F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:56672 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i8Aky-0001RI-R1 for qemu-devel@archiver.kernel.org; Wed, 11 Sep 2019 18:06:32 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:36674) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i8Aia-0007yd-6h for qemu-devel@nongnu.org; Wed, 11 Sep 2019 18:04:05 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i8AiZ-0002Hr-37 for qemu-devel@nongnu.org; Wed, 11 Sep 2019 18:04:04 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54146) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1i8AiT-0002Dg-TM; Wed, 11 Sep 2019 18:03:58 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 7D4F218C426C; Wed, 11 Sep 2019 22:03:56 +0000 (UTC) Received: from [10.3.116.234] (ovpn-116-234.phx2.redhat.com [10.3.116.234]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 7E73467630; Wed, 11 Sep 2019 22:03:53 +0000 (UTC) To: Sergio Lopez , qemu-block@nongnu.org References: <20190911161521.59261-1-slp@redhat.com> <6755b34b-b412-9e63-8d25-b7662d0d3860@redhat.com> From: Eric Blake Openpgp: preference=signencrypt Autocrypt: addr=eblake@redhat.com; keydata= xsBNBEvHyWwBCACw7DwsQIh0kAbUXyqhfiKAKOTVu6OiMGffw2w90Ggrp4bdVKmCaEXlrVLU xphBM8mb+wsFkU+pq9YR621WXo9REYVIl0FxKeQo9dyQBZ/XvmUMka4NOmHtFg74nvkpJFCD TUNzmqfcjdKhfFV0d7P/ixKQeZr2WP1xMcjmAQY5YvQ2lUoHP43m8TtpB1LkjyYBCodd+LkV GmCx2Bop1LSblbvbrOm2bKpZdBPjncRNob73eTpIXEutvEaHH72LzpzksfcKM+M18cyRH+nP sAd98xIbVjm3Jm4k4d5oQyE2HwOur+trk2EcxTgdp17QapuWPwMfhaNq3runaX7x34zhABEB AAHNHkVyaWMgQmxha2UgPGVibGFrZUByZWRoYXQuY29tPsLAegQTAQgAJAIbAwULCQgHAwUV CgkICwUWAgMBAAIeAQIXgAUCS8fL9QIZAQAKCRCnoWtKJSdDahBHCACbl/5FGkUqJ89GAjeX RjpAeJtdKhujir0iS4CMSIng7fCiGZ0fNJCpL5RpViSo03Q7l37ss+No+dJI8KtAp6ID+PMz wTJe5Egtv/KGUKSDvOLYJ9WIIbftEObekP+GBpWP2+KbpADsc7EsNd70sYxExD3liwVJYqLc Rw7so1PEIFp+Ni9A1DrBR5NaJBnno2PHzHPTS9nmZVYm/4I32qkLXOcdX0XElO8VPDoVobG6 gELf4v/vIImdmxLh/w5WctUpBhWWIfQDvSOW2VZDOihm7pzhQodr3QP/GDLfpK6wI7exeu3P pfPtqwa06s1pae3ad13mZGzkBdNKs1HEm8x6zsBNBEvHyWwBCADGkMFzFjmmyqAEn5D+Mt4P zPdO8NatsDw8Qit3Rmzu+kUygxyYbz52ZO40WUu7EgQ5kDTOeRPnTOd7awWDQcl1gGBXgrkR pAlQ0l0ReO57Q0eglFydLMi5bkwYhfY+TwDPMh3aOP5qBXkm4qIYSsxb8A+i00P72AqFb9Q7 3weG/flxSPApLYQE5qWGSXjOkXJv42NGS6o6gd4RmD6Ap5e8ACo1lSMPfTpGzXlt4aRkBfvb NCfNsQikLZzFYDLbQgKBA33BDeV6vNJ9Cj0SgEGOkYyed4I6AbU0kIy1hHAm1r6+sAnEdIKj cHi3xWH/UPrZW5flM8Kqo14OTDkI9EtlABEBAAHCwF8EGAEIAAkFAkvHyWwCGwwACgkQp6Fr SiUnQ2q03wgAmRFGDeXzc58NX0NrDijUu0zx3Lns/qZ9VrkSWbNZBFjpWKaeL1fdVeE4TDGm I5mRRIsStjQzc2R9b+2VBUhlAqY1nAiBDv0Qnt+9cLiuEICeUwlyl42YdwpmY0ELcy5+u6wz mK/jxrYOpzXKDwLq5k4X+hmGuSNWWAN3gHiJqmJZPkhFPUIozZUCeEc76pS/IUN72NfprZmF Dp6/QDjDFtfS39bHSWXKVZUbqaMPqlj/z6Ugk027/3GUjHHr8WkeL1ezWepYDY7WSoXwfoAL 2UXYsMAr/uUncSKlfjvArhsej0S4zbqim2ZY6S8aRWw94J3bSvJR+Nwbs34GPTD4Pg== Organization: Red Hat, Inc. Message-ID: <5c1488f6-00ed-9d28-f544-a198f2fada94@redhat.com> Date: Wed, 11 Sep 2019 17:03:52 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <6755b34b-b412-9e63-8d25-b7662d0d3860@redhat.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="97qlybAIkBaT7TdCl8bzEXq0oFQLPn4gv" X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.62]); Wed, 11 Sep 2019 22:03:56 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH] nbd/server: attach client channel to the export's AioContext 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: , Cc: kwolf@redhat.com, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --97qlybAIkBaT7TdCl8bzEXq0oFQLPn4gv Content-Type: multipart/mixed; boundary="w21t4e7s8AhhjqpxUAPx7NMhyL1aDBGFC"; protected-headers="v1" From: Eric Blake To: Sergio Lopez , qemu-block@nongnu.org Cc: kwolf@redhat.com, qemu-devel@nongnu.org Message-ID: <5c1488f6-00ed-9d28-f544-a198f2fada94@redhat.com> Subject: Re: [PATCH] nbd/server: attach client channel to the export's AioContext References: <20190911161521.59261-1-slp@redhat.com> <6755b34b-b412-9e63-8d25-b7662d0d3860@redhat.com> In-Reply-To: <6755b34b-b412-9e63-8d25-b7662d0d3860@redhat.com> --w21t4e7s8AhhjqpxUAPx7NMhyL1aDBGFC Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 9/11/19 4:33 PM, Eric Blake wrote: > I tried to test this patch, but even with it applied, I still got an > aio-context crasher by attempting an nbd-server-start, nbd-server-add, > nbd-server-stop (intentionally skipping the nbd-server-remove step) on = a > domain using iothreads, with a backtrace of: The crash also reproduces with nbd-server-remove instead of nbd-server-stop. Both QMP commands eventually call into the blk_remove_bs() that calls the fatal blk_drain(). So libvirt can't work around the bug merely by adding an nbd-server-remove step. >=20 > #0 0x00007ff09d070e35 in raise () from target:/lib64/libc.so.6 > #1 0x00007ff09d05b895 in abort () from target:/lib64/libc.so.6 > #2 0x000055dd03b9ab86 in error_exit (err=3D1, msg=3D0x55dd03d59fb0 > <__func__.15769> "qemu_mutex_unlock_impl") > at util/qemu-thread-posix.c:36 > #3 0x000055dd03b9adcf in qemu_mutex_unlock_impl (mutex=3D0x55dd062d509= 0, > file=3D0x55dd03d59041 "util/async.c", > line=3D523) at util/qemu-thread-posix.c:96 > #4 0x000055dd03b93433 in aio_context_release (ctx=3D0x55dd062d5030) at= > util/async.c:523 > #5 0x000055dd03ac421b in bdrv_do_drained_begin (bs=3D0x55dd0673a2d0, > recursive=3Dfalse, parent=3D0x0, > ignore_bds_parents=3Dfalse, poll=3Dtrue) at block/io.c:428 > #6 0x000055dd03ac4299 in bdrv_drained_begin (bs=3D0x55dd0673a2d0) at > block/io.c:434 > #7 0x000055dd03aafb54 in blk_drain (blk=3D0x55dd06a3ec40) at > block/block-backend.c:1605 > #8 0x000055dd03aae054 in blk_remove_bs (blk=3D0x55dd06a3ec40) at > block/block-backend.c:800 --=20 Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3226 Virtualization: qemu.org | libvirt.org --w21t4e7s8AhhjqpxUAPx7NMhyL1aDBGFC-- --97qlybAIkBaT7TdCl8bzEXq0oFQLPn4gv Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEccLMIrHEYCkn0vOqp6FrSiUnQ2oFAl15b0gACgkQp6FrSiUn Q2piYwf/UtTIo4QAUkecq0CoSL6CnE3ISc393I+aKoRKKL/SQ2PzhCS9qylMr6Vk oeA+E7nuzL3STLDmkRYBOSqjC0BkG0O/10P+QlM6g9yM5mtq1pSvY4/5IUDLJKUE ZVprx53F5ZstlPHOC9/w0GEF/zB2HyzIkMrvaqjosZrBZSn4OEndzYDIn/AXo7DC uu2hdk/hvUMTG9HTQl8Mr5DJx+fMV8YZU6wzC807bAw5tbS3ahNZmkYpanWEqwb4 QGoPVkv0FIWu8bGZ/ULDBoxJhFe4Jb3+j5zoudmQl/arzWZaJjMEmA+1zqAkquSE aWmuJUHsySc4dITiQ/nThf9d7xCW3Q== =+NP4 -----END PGP SIGNATURE----- --97qlybAIkBaT7TdCl8bzEXq0oFQLPn4gv--