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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 501C9C433EF for ; Mon, 7 Mar 2022 22:21:32 +0000 (UTC) Received: from localhost ([::1]:33430 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nRLjP-0003di-Cb for qemu-devel@archiver.kernel.org; Mon, 07 Mar 2022 17:21:31 -0500 Received: from eggs.gnu.org ([209.51.188.92]:47968) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nRLdX-0006Ny-Qn for qemu-devel@nongnu.org; Mon, 07 Mar 2022 17:15:27 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:39297) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nRLdT-00016R-0Y for qemu-devel@nongnu.org; Mon, 07 Mar 2022 17:15:27 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1646691322; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=uX2xYOfks0dxXpJ5arraJ4+qoeIBhRVJhy65dmuNaRM=; b=NULUWy7xjKC4djHgzx35S35PSXBalVWpJg7Z2/rITzocJ0tmCXCTmSftbvaM+bxc2aWWS7 yxkZgy4vxcQhWkRJ8oqf3abgLyk25jynhqN02TrWjfthB4orcdqToPWRBKc0l5txC071Qn 7I23aBlRGi9NLM4CzDwrEDD/liz9aKA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-345-Nm3ajl2xNGW6KGsWf41j1w-1; Mon, 07 Mar 2022 17:15:21 -0500 X-MC-Unique: Nm3ajl2xNGW6KGsWf41j1w-1 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 mimecast-mx01.redhat.com (Postfix) with ESMTPS id 07067800D55; Mon, 7 Mar 2022 22:15:20 +0000 (UTC) Received: from scv.redhat.com (unknown [10.22.10.176]) by smtp.corp.redhat.com (Postfix) with ESMTP id 039515E253; Mon, 7 Mar 2022 22:15:18 +0000 (UTC) From: John Snow To: qemu-devel@nongnu.org Subject: [PULL 09/11] python/aqmp: fix race condition in legacy.py Date: Mon, 7 Mar 2022 17:15:05 -0500 Message-Id: <20220307221507.1218892-10-jsnow@redhat.com> In-Reply-To: <20220307221507.1218892-1-jsnow@redhat.com> References: <20220307221507.1218892-1-jsnow@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jsnow@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=170.10.129.124; envelope-from=jsnow@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Peter Maydell , =?UTF-8?q?Daniel=20P=20=2E=20Berrang=C3=A9?= , Beraldo Leal , qemu-block@nongnu.org, Markus Armbruster , Eduardo Habkost , Hanna Reitz , Cleber Rosa , John Snow Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" legacy.py provides a synchronous model. iotests frequently uses this paradigm: - create QMP client object - start QEMU process - await connection from QEMU process In the switch from sync to async QMP, the QMP client object stopped calling bind() and listen() during the QMP object creation step, which creates a race condition if the QEMU process dials in too quickly. With refactoring out of the way, restore the former behavior of calling bind() and listen() during __init__() to fix this race condition. Signed-off-by: John Snow Acked-by: Kevin Wolf Reviewed-by: Daniel P. Berrangé Message-id: 20220225205948.3693480-10-jsnow@redhat.com [Expanded commit message. --js] Signed-off-by: John Snow --- python/qemu/aqmp/legacy.py | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/python/qemu/aqmp/legacy.py b/python/qemu/aqmp/legacy.py index dca1e76ed4..cb50e60564 100644 --- a/python/qemu/aqmp/legacy.py +++ b/python/qemu/aqmp/legacy.py @@ -57,7 +57,7 @@ def __init__(self, address: SocketAddrT, self._timeout: Optional[float] = None if server: - self._aqmp._bind_hack(address) # pylint: disable=protected-access + self._sync(self._aqmp.start_server(address)) _T = TypeVar('_T') @@ -90,10 +90,7 @@ def accept(self, timeout: Optional[float] = 15.0) -> QMPMessage: self._aqmp.await_greeting = True self._aqmp.negotiate = True - self._sync( - self._aqmp.start_server_and_accept(self._address), - timeout - ) + self._sync(self._aqmp.accept(), timeout) ret = self._get_greeting() assert ret is not None -- 2.34.1