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=-10.4 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 DBF03C433E0 for ; Fri, 5 Feb 2021 19:08:27 +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 2B39C64DFF for ; Fri, 5 Feb 2021 19:08:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2B39C64DFF 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]:58224 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l86Sv-00056D-Ry for qemu-devel@archiver.kernel.org; Fri, 05 Feb 2021 14:08:25 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:44820) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l86P2-00035p-BB for qemu-devel@nongnu.org; Fri, 05 Feb 2021 14:04:24 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:38053) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1l86Ow-0006Ed-4X for qemu-devel@nongnu.org; Fri, 05 Feb 2021 14:04:23 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612551856; 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=YM/9Q6x1TGBrPzmZdzTgxv0gdyBOuXCdACYIn5KYe3Y=; b=TZclFS2CakBDhVv5xlw7M2NP1gCJNQsXdAHdMh+WiTXqoFfbhRx4xHwHLnj54YOKwfbV7q 4G0gZPdW+QKfbJ3usqwqKV/sVwH0kOHB5CHLUzSzTTPde28AsOfJhCm+CMVmENXDNRHk/J DLOpqjc++9+AiAHUdnixjbOElVXusQo= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-436--7UqF_XUOCu50lRFLkVPBg-1; Fri, 05 Feb 2021 14:04:13 -0500 X-MC-Unique: -7UqF_XUOCu50lRFLkVPBg-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A8B66803F49; Fri, 5 Feb 2021 19:04:12 +0000 (UTC) Received: from [10.3.112.253] (ovpn-112-253.phx2.redhat.com [10.3.112.253]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 4519119712; Fri, 5 Feb 2021 19:04:09 +0000 (UTC) Subject: Re: [PATCH] sockets: Use SOMAXCONN for Unix socket listen() To: =?UTF-8?Q?Daniel_P=2e_Berrang=c3=a9?= References: <20210204222018.1432848-1-eblake@redhat.com> <20210205095548.GC908621@redhat.com> From: Eric Blake Organization: Red Hat, Inc. Message-ID: Date: Fri, 5 Feb 2021 13:04:08 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.0 MIME-Version: 1.0 In-Reply-To: <20210205095548.GC908621@redhat.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eblake@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=63.128.21.124; envelope-from=eblake@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.352, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.33, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham 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: Gerd Hoffmann , qemu-devel@nongnu.org, qemu-block@nongnu.org, rjones@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 2/5/21 3:55 AM, Daniel P. Berrangé wrote: >> +++ b/util/qemu-sockets.c >> @@ -1059,7 +1059,7 @@ int unix_listen(const char *str, Error **errp) >> >> saddr = g_new0(UnixSocketAddress, 1); >> saddr->path = g_strdup(str); >> - sock = unix_listen_saddr(saddr, 1, errp); >> + sock = unix_listen_saddr(saddr, SOMAXCONN, errp); >> qapi_free_UnixSocketAddress(saddr); >> return sock; >> } > > This method is a legacy back compat function, only used by the QEMU > guest agent, so this can't explain the NBD problems, which use the > QIONetListener class. > > IOW, the problem is in the qemu-nbd.c / blockdev-nbd.c code I believe D'oh. Serves me right for trying to guess the spot using just a grep on listen() rather than running under gdb with a breakpoint to find the actual backtrace. v2 posted with a slightly changed subject line, and this time tested to actually work. -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3226 Virtualization: qemu.org | libvirt.org