From patchwork Mon Dec 28 15:08:37 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Lukas Straub X-Patchwork-Id: 11991283 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=-5.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,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 6084FC433DB for ; Mon, 28 Dec 2020 15:14:26 +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 08411207A1 for ; Mon, 28 Dec 2020 15:14:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 08411207A1 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=web.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:59636 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ktuE5-00014b-7p for qemu-devel@archiver.kernel.org; Mon, 28 Dec 2020 10:14:25 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:49522) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ktu8d-00041U-7Q; Mon, 28 Dec 2020 10:08:47 -0500 Received: from mout.web.de ([212.227.15.3]:53097) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ktu8b-00017e-1P; Mon, 28 Dec 2020 10:08:46 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=web.de; s=dbaedf251592; t=1609168119; bh=ohPKNr06lzv2cp+agPBxRAixWxLFxxGPZhNxuXnPRkE=; h=X-UI-Sender-Class:Date:From:To:Cc:Subject; b=qt7lTbJ6Wiepxtnz0Cz2B6t/0Rg0LtZqkfEyE8p6gHWUp0BFYK15d5KBCbg4RqQgI 00ytDoHCZ1XM+JBhgI4AiUMB3mTRQelZU2mHmSIiBNtdJ9nqllsR5mN9agEuztAJqN tMQ3LhzFb5wXcDJxbe3yFwt97nvELaLLzvxd8aFY= X-UI-Sender-Class: c548c8c5-30a9-4db5-a2e7-cb6cb037b8f9 Received: from gecko.fritz.box ([94.134.180.94]) by smtp.web.de (mrweb005 [213.165.67.108]) with ESMTPSA (Nemesis) id 1MhWop-1kPEHN3bwB-00eG5X; Mon, 28 Dec 2020 16:08:38 +0100 Date: Mon, 28 Dec 2020 16:08:37 +0100 From: Lukas Straub To: qemu-devel Subject: [PATCH v14 0/7] Introduce 'yank' oob qmp command to recover from hanging qemu Message-ID: MIME-Version: 1.0 X-Provags-ID: V03:K1:wuKpvMTs1KuVJ55tyoaos+rembP2I7l16zZTzaeV9IoWhILTOyV 34DfA8QDhSDS7w7EWWFs/YiAL/gRVaHhGAojVzwreFMfsHRGjbFDSKe0s5L5yUPrMThL1Mw WRrWsk5BSWOS9lIEYON/jywyulslhqpbNhr6++si7ykD2u1ywv10RmdN7Tp6oFPzy3atVcT gJakw2ESInUxoS7AABRWA== X-UI-Out-Filterresults: notjunk:1;V03:K0:AVE+MJkW1Ws=:dXadi0JgT8/R7d8KverZuG y3MjC6zi8JZmxwqLYe011HArs43uL2ly6i9izZwTx55w3FK1pjDQOwlR5B6yy/KdOO6b5bP0b kgfdUkdNMjmYzYKzYdrEpH+yDBgbiA4NCsiIEqKS7ZMntaKWapcF1gYtVEbumXvx3j/ODZVxd 2Tnd5xAxDHUVc5X6vejjZdF2udrFcG0g+L2AT/+oOCKQdx0E15prqNQMx2e4n0EQ/8zDI+C8T wdWz2VfvDE21BtpNAaej7hLfp4TVMR7PVpKWk+RK+s0+LXkDFni3wHRrdrgOg6xrCYeeC+Y7h qh4G7BwnMXokj0REffe1pgdYnqyi2ipd2wvQM5zacyboJ/1mJgC3PnYaBUfZBp53JDKR5JxbX td65yB1M4dizg5n4rUu0mnmj7eDZJEP6lLhYfmfwqwunxSI6pCyrIAsQMo++JXqyYlklUqULG 63IWnEJhFRBs7MCO5C5ENk4GIoannivjpwdjOIzs6fGlXtlSgSm6gzb7wYJ0SCR7G1UO+dBBV PNNZL15Rn7BF5OamE/w6JKgnbHawekCRwB7SkLZ5NEuweLsHG2saISi1nDOTzdU1c6VkvAUEW 2XqrDgML2ewpvxPaaWkblpq51dTIZrbmIyqmUVREkQpp6xaE56Nl4kQJprVLCmn6HeuT1ZlPj iSC37Ovn2pUULRVjNT2UBEjLiHhAUXXKaDTJVQYzsr08b2KwOupXL8RN8YgCkk7lY8BGVvmRB 6mzKrYDrPt3kYChX+f2Ff4GbDRQm9X2bKnXmSQ75MVqWDlyYePlDyryfvyIp5S/vSjqeaAzCB gSPYUpEPainyXI5hYMGERk0tuYsyX3T63agJl/ctVnAmgG6+5TmyRUYrbR0YfuxS89xr4uzzr 829fCBfs5Kihq99ZUXmSu3LRCTFHghGV3XU3K8H6U= Received-SPF: pass client-ip=212.227.15.3; envelope-from=lukasstraub2@web.de; helo=mout.web.de X-Spam_score_int: -9 X-Spam_score: -1.0 X-Spam_bar: - X-Spam_report: (-1.0 / 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_SORBS_WEB=1.5, 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: Kevin Wolf , "Daniel P. =?utf-8?q?Berrang=C3=A9=5C?= " , qemu-block , Juan Quintela , Markus Armbruster , "Dr. David Alan Gilbert" , Max Reitz , =?utf-8?q?Marc-Andr=C3=A9?= Lureau , Paolo Bonzini , =?utf-8?q?Marc-Andr=C3=A9?= Lureau Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Hello Everyone, So here is v14. Changes: v14: -fix checkpatch.pl warning v13: -Address Marc-André Lureau comments: -make yank_register_instance return bool -rename yank_compare_instances to yank_instance_equal -remove breaks -use g_str_equal instead of strcmp -use g_new0 instead of g_slice_new -use QEMU_LOCK_GUARD instead of qemu_mutex_lock/unlock v12: -rebase onto master -minor change to migration (removal of "defer" branch in qemu_start_incoming_migration) -add Reviewed-by tags v11: -squashed MAINTAINERS update into patch 1 -move qmp doc of yank before misc -add title for qmp docs -change "Since:" to 6.0 -add Reviewed-by tags v10: -moved from qapi/misc.json to qapi/yank.json -rename 'blockdev' -> 'block-node' -document difference betwen migration yank instance and migrate_cancel -better document return values of yank command -better document yank_lock -minor style and spelling fixes v9: -rebase onto master -implemented new qmp api as proposed by Markus v8: -add Reviewed-by and Acked-by tags -rebase onto master -minor change to migration -convert to meson -change "Since:" to 5.2 -varios code style fixes (Markus Armbruster) -point to oob restrictions in comment to yank_register_function (Markus Armbruster) -improve qmp documentation (Markus Armbruster) -document oob suitability of qio_channel and io_shutdown (Markus Armbruster) v7: -yank_register_instance now returns error via Error **errp instead of aborting -dropped "chardev/char.c: Check for duplicate id before creating chardev" v6: -add Reviewed-by and Acked-by tags -rebase on master -lots of changes in nbd due to rebase -only take maintainership of util/yank.c and include/qemu/yank.h (Daniel P. Berrangé) -fix a crash discovered by the newly added chardev test -fix the test itself v5: -move yank.c to util/ -move yank.h to include/qemu/ -add license to yank.h -use const char* -nbd: use atomic_store_release and atomic_load_aqcuire -io-channel: ensure thread-safety and document it -add myself as maintainer for yank v4: -fix build errors... v3: -don't touch softmmu/vl.c, use __contructor__ attribute instead (Paolo Bonzini) -fix build errors -rewrite migration patch so it actually passes all tests v2: -don't touch io/ code anymore -always register yank functions -'yank' now takes a list of instances to yank -'query-yank' returns a list of yankable instances Overview: Hello Everyone, In many cases, if qemu has a network connection (qmp, migration, chardev, etc.) to some other server and that server dies or hangs, qemu hangs too. These patches introduce the new 'yank' out-of-band qmp command to recover from these kinds of hangs. The different subsystems register callbacks which get executed with the yank command. For example the callback can shutdown() a socket. This is intended for the colo use-case, but it can be used for other things too of course. Regards, Lukas Straub Lukas Straub (7): Introduce yank feature block/nbd.c: Add yank feature chardev/char-socket.c: Add yank feature migration: Add yank feature io/channel-tls.c: make qio_channel_tls_shutdown thread-safe io: Document qmp oob suitability of qio_channel_shutdown and io_shutdown tests/test-char.c: Wait for the chardev to connect in char_socket_client_dupid_test MAINTAINERS | 7 ++ block/nbd.c | 153 +++++++++++++++---------- chardev/char-socket.c | 34 ++++++ include/io/channel.h | 5 +- include/qemu/yank.h | 97 ++++++++++++++++ io/channel-tls.c | 6 +- migration/channel.c | 13 +++ migration/migration.c | 22 ++++ migration/multifd.c | 10 ++ migration/qemu-file-channel.c | 7 ++ migration/savevm.c | 5 + qapi/meson.build | 1 + qapi/qapi-schema.json | 1 + qapi/yank.json | 119 +++++++++++++++++++ tests/test-char.c | 1 + util/meson.build | 1 + util/yank.c | 207 ++++++++++++++++++++++++++++++++++ 17 files changed, 625 insertions(+), 64 deletions(-) create mode 100644 include/qemu/yank.h create mode 100644 qapi/yank.json create mode 100644 util/yank.c --- 2.29.2