From patchwork Wed Aug 4 19:26:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Straub X-Patchwork-Id: 12419709 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=-10.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 DF4C2C4338F for ; Wed, 4 Aug 2021 19:27:48 +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 5C8DB60F58 for ; Wed, 4 Aug 2021 19:27:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 5C8DB60F58 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=web.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:58272 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mBMYN-0003OT-9f for qemu-devel@archiver.kernel.org; Wed, 04 Aug 2021 15:27:47 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:39846) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mBMXb-0002ii-56 for qemu-devel@nongnu.org; Wed, 04 Aug 2021 15:26:59 -0400 Received: from mout.web.de ([212.227.15.3]:47019) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mBMXY-0001AK-VZ for qemu-devel@nongnu.org; Wed, 04 Aug 2021 15:26:58 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=web.de; s=dbaedf251592; t=1628105209; bh=8EEPpVjM0AndmxcfkYrypMVyCVvu7/qREydgEtXQOdQ=; h=X-UI-Sender-Class:Date:From:To:Cc:Subject; b=C90DSwdYU4zguBcDBf4kODOtGCviRdVGyx9ZDkCEbj3MeQY/gm5BSMnCYF41EE2M0 Z3BxoHVAe6FPWlPLaWwpfBNlj2pdbkz+ASoSzismouI+a2qoLlPmDfz1CrYlh+O3g1 OXgTnvWyYFa+YFcT/3FpzMb4HrHp8NTWGYhmLIoY= X-UI-Sender-Class: c548c8c5-30a9-4db5-a2e7-cb6cb037b8f9 Received: from gecko.fritz.box ([94.134.180.254]) by smtp.web.de (mrweb006 [213.165.67.108]) with ESMTPSA (Nemesis) id 1MDMzC-1mKgSl2xDa-00ArOq; Wed, 04 Aug 2021 21:26:49 +0200 Date: Wed, 4 Aug 2021 21:26:32 +0200 From: Lukas Straub To: qemu-devel Subject: [PATCH for 6.1] multifd: Unconditionally unregister yank function Message-ID: <20210804212632.77221bcf@gecko.fritz.box> MIME-Version: 1.0 X-Provags-ID: V03:K1:xspzGkQx+qDWuLinIPr5xN5OWikSqYAKnHDCeHhyttlJepICaSB 1ItNu3fyaaYPjvYxbJEFmlJoIPU+vuyG+yqUqaKSulG5L/V08DUqihfovzzAkOPkwPX23SB dG6qGxyUpinMjeZNJWr6zJJc0HjtLKRUvPEa1Obfhe+VO6OyfA1zeJ8NC7reOV02FAZi/aH QHzA2tUf7J3FQnW6+2iWw== X-UI-Out-Filterresults: notjunk:1;V03:K0:JCDZUe/UxI0=:D7nO5rRUPIRvKlzV2CvOc5 iaDLHjQagA6FWa/T5H+XZU/f5hN+1zOvrKK9Y2+pJB/hLogPNpkv17rh+S3tBYB6Dhipz0Erv /pkjM1rM+2yyxtbQQ5ZcSn2cPlD390rS/ARSUxWFA7Dx7tn4ItxktEtQEMbbWOg4zTerxw6DG DSXp19TMPt8lt13gCHcbSMouFkTkpB1FcxgliiY3zocbHqjtHt/Y0zF1L7ipyU2GTvjGNrYLI rDhXG+HbGOabgdWXcE/xnLfs7F+KM2C7D6CngtEBbaUXXnYbz9XZUZI/eXZqf0B3mDdBL8aND AzvEW44eCaiuOFl66nWLVg+ntQ+EZgodZETCZnDsFrzsdi2P725QbCFf2SQ1leoayXOk3ZEMh VjyZlTnT3RC7ao3zjcHaa4wAhoEzNJYzhQe/AhlI16lwNKVEFdTXuGx3muDzGAgCDoGcv0YPP 1+WcBwwPJ+k40LulRCr9UKG6eCjPvL9zkU6fj+xQh1nYzTn5kNAL1wURDBmIfG+lI0lkxMJr9 nr4H4pRJqz2tPYlW7vwUNEpmQmK9ub+kqldTD+QAdSVF0nrPOFqWKA3Lh7yAC/xPQf9CmKZUm Tc8hZA2Pnv5fDfWEwKrMOl1gKl8mGcBjpEQH2vsUpFv7AN0rOccZRPfOtUYwEXxq4WOq+elQ6 blP7mrB+vMj+/k7E9OG/wAvustUrv8s19KvHbdsFnDsKc5FiTEEar8DygTiLrHpvg9zBZqXai uX77zFKg9TT799od030GrA3TYPsBRVDhoU+C92XhQAnapqFWNcOrJZD8solnZCWXRmushsl3n KDOK2TgxIEphgbeNCDa/UeNyRcknC/SNOnCFtd+0z8EN6DgXIz9KwHNLVp7W3I0tdYkV2Af9f 3UJYF7Cuczvy67ja65sAa8vD7k/LQv1Nr2OOLfmndyUjBNp8rnuFP4Ux41S0zACJwE0aYARsE n7P4f62tDNBDwVjqRpKabFaFDmwOlRUvMdZTg9VKzmCbsoLAUR8mOOG6awBLKibUXjuoH1XCP pWNBK/zK+1Xqb6UJIimwYwU82m9aWLe9GHIpt+lQ6amjqAHUymiOCbAp08BkLRmn/tO+4nQVr 77ea5Qczg+aqBemunotkUjIX/i7owQCOXfc8tumzvMiFmR3wfcXPLxrXIRQ3TeOfHwwEabfkh dwbs8= Received-SPF: pass client-ip=212.227.15.3; envelope-from=lukasstraub2@web.de; helo=mout.web.de X-Spam_score_int: 8 X-Spam_score: 0.8 X-Spam_bar: / X-Spam_report: (0.8 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_ENVFROM_END_DIGIT=0.25, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_SBL_CSS=3.335, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action 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: Leonardo Bras Soares Passos , "Dr. David Alan Gilbert" , Peter Xu , Juan Quintela Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Unconditionally unregister yank function in multifd_load_cleanup(). If it is not unregistered here, it will leak and cause a crash in yank_unregister_instance(). Now if the ioc is still in use afterwards, it will only lead to qemu not being able to recover from a hang related to that ioc. After checking the code, i am pretty sure that ref is always 1 when arriving here. So all this currently does is remove the unneeded check. Signed-off-by: Lukas Straub Reviewed-by: Juan Quintela --- This is similar to Peter Xu's 39675ffffb3394d44b880d083a214c5e44786170 "migration: Move the yank unregister of channel_close out" in that it removes the "OBJECT(p->c)->ref == 1" hack. So it makes sense for 6.1 so these patches are together. migration/multifd.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/migration/multifd.c b/migration/multifd.c index 377da78f5b..a37805e17e 100644 --- a/migration/multifd.c +++ b/migration/multifd.c @@ -987,10 +987,7 @@ int multifd_load_cleanup(Error **errp) for (i = 0; i < migrate_multifd_channels(); i++) { MultiFDRecvParams *p = &multifd_recv_state->params[i]; - if (OBJECT(p->c)->ref == 1) { - migration_ioc_unregister_yank(p->c); - } - + migration_ioc_unregister_yank(p->c); object_unref(OBJECT(p->c)); p->c = NULL; qemu_mutex_destroy(&p->mutex);