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=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 0F359C5DF61 for ; Thu, 7 Nov 2019 14:44:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D56E6214D8 for ; Thu, 7 Nov 2019 14:44:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="atOJhmTi" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727142AbfKGOod (ORCPT ); Thu, 7 Nov 2019 09:44:33 -0500 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:47834 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726754AbfKGOod (ORCPT ); Thu, 7 Nov 2019 09:44:33 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1573137872; 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=uokYutLXxZLmrspkhT2MmzUiCDD5/pP/FDqbke/Wsbo=; b=atOJhmTiL4tnqM4j00PnLlT406NpbmVzn5I5ZeirZviTQOHfIjXEWu4mqSPdJQk+yB4YCt Bb6nphQfcRNwdeDiINfWYfVNTT+1hMNYTzeWvoc2VutlEOCZq59+RJPLft+47gYO4jUGEu De7IDW7/dx7kbDVnxnDy5SRXdlaU+Sw= Received: from mail-wr1-f71.google.com (mail-wr1-f71.google.com [209.85.221.71]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-33-oiXkTUqxOzeVuCRjgHemNw-1; Thu, 07 Nov 2019 09:44:31 -0500 Received: by mail-wr1-f71.google.com with SMTP id e7so1139170wro.22 for ; Thu, 07 Nov 2019 06:44:30 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=gVCbv0LzqaX/qvKbIQst3PDmSY4xjmIqqe/yjz+5HCQ=; b=E1B9xcF8J+0GOQZzLl/MfClr1qWOL91Rl4hLDEfzHWkWeqimz7Ld16UvSn+6qO/eTy MXPkOPgnZRNWrPguSCA6lqwmK8+rfwmVSPpBNT74IP/wf8+vB+SxauXqI+yYtu5waTeP CkHg54EX8UZgvn8n2gUy7q3BMTv9F/uH96JA+85/J4C8YdynVr4snXA4MmzeBro1s+iE 79Iu9hDO177ZpmyVLfiukr1PednIbVK02zM28oE9LqEMDQNRGeivrceRWUD//NDbVqjo cFsIZySsQCOlkAP8T6JwHjGXRn4qK9yWovliqciGDTCStRxF3wGf3Lbbob6bnpwwLE7m eyvA== X-Gm-Message-State: APjAAAXlKo2hkBNlmxyNBa/tdJMkdjjz6mdpjSl9TAwE/KlCZj8sxkIT +TWhDUZxPjSUzrkjUCFJmHYMLzEb14SwKuJLNvpW3Ju7ixvEvBZGbPjPBdJeOKWlvOWLzb8GMuj frDByAMsjzmuG6XuuPybLWybh X-Received: by 2002:adf:f048:: with SMTP id t8mr3418714wro.237.1573137869677; Thu, 07 Nov 2019 06:44:29 -0800 (PST) X-Google-Smtp-Source: APXvYqxUI1JLHk53Xg60Bfi3+RoW23Um++7OLDP36Ol51PbWYQBdWIxnkrQYImvKgZXpd3GbH1R6MQ== X-Received: by 2002:adf:f048:: with SMTP id t8mr3418652wro.237.1573137868856; Thu, 07 Nov 2019 06:44:28 -0800 (PST) Received: from vitty.brq.redhat.com (nat-pool-brq-t.redhat.com. [213.175.37.10]) by smtp.gmail.com with ESMTPSA id z14sm2475247wrl.60.2019.11.07.06.44.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 07 Nov 2019 06:44:28 -0800 (PST) From: Vitaly Kuznetsov To: Olaf Hering Cc: "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , Sasha Levin , "open list\:Hyper-V CORE AND DRIVERS" , open list Subject: Re: [PATCH v1] tools/hv: async name resolution in kvp_daemon In-Reply-To: <20191107152059.6cae8f30.olaf@aepfle.de> References: <20191024144943.26199-1-olaf@aepfle.de> <874kzfbybk.fsf@vitty.brq.redhat.com> <20191107144850.37587edb.olaf@aepfle.de> <87zhh7ai26.fsf@vitty.brq.redhat.com> <20191107152059.6cae8f30.olaf@aepfle.de> Date: Thu, 07 Nov 2019 15:44:27 +0100 Message-ID: <87wocbagqc.fsf@vitty.brq.redhat.com> MIME-Version: 1.0 X-MC-Unique: oiXkTUqxOzeVuCRjgHemNw-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable Sender: linux-hyperv-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org Olaf Hering writes: > Am Thu, 07 Nov 2019 15:15:45 +0100 > schrieb Vitaly Kuznetsov : > >> Looping forever with a permanent error is pretty unusual... > > That might be true, but how would you detect a permanent error? > Just because the DNS server is gone for one hour does not mean it will be= gone forever. 'man 3 getaddrinfo' lists the following: EAI_ADDRFAMILY EAI_AGAIN EAI_BADFLAGS EAI_FAIL EAI_FAMILY EAI_MEMORY EAI_NODATA EAI_NONAME EAI_SERVICE EAI_SOCKTYPE EAI_SYSTEM I *think* what you're aiming at is EAI_AGAIN and EAI_FAIL, the rest should probably terminate the resolver thread (e.g. AF_INET is unsupported or something like that). --=20 Vitaly