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=-5.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,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 7B8A4C433E0 for ; Wed, 3 Feb 2021 17:24:53 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 08B6064F4B for ; Wed, 3 Feb 2021 17:24:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 08B6064F4B Authentication-Results: mail.kernel.org; dmarc=pass (p=none dis=none) header.from=xenproject.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.80987.148746 (Exim 4.92) (envelope-from ) id 1l7LtO-00073i-Uf; Wed, 03 Feb 2021 17:24:38 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 80987.148746; Wed, 03 Feb 2021 17:24:38 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1l7LtO-00073b-Qy; Wed, 03 Feb 2021 17:24:38 +0000 Received: by outflank-mailman (input) for mailman id 80987; Wed, 03 Feb 2021 17:24:37 +0000 Received: from mail.xenproject.org ([104.130.215.37]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1l7LtN-00073W-Ny for xen-devel@lists.xenproject.org; Wed, 03 Feb 2021 17:24:37 +0000 Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1l7LtN-0004ll-KY for xen-devel@lists.xenproject.org; Wed, 03 Feb 2021 17:24:37 +0000 Received: from iwj (helo=mariner.uk.xensource.com) by xenbits.xenproject.org with local-bsmtp (Exim 4.92) (envelope-from ) id 1l7LtN-0000aQ-EU for xen-devel@lists.xenproject.org; Wed, 03 Feb 2021 17:24:37 +0000 Received: from iwj by mariner.uk.xensource.com with local (Exim 4.89) (envelope-from ) id 1l7LtK-0005ZH-AG; Wed, 03 Feb 2021 17:24:34 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=xenproject.org; s=20200302mail; h=References:In-Reply-To:Subject:Cc:To:Date :Message-ID:Content-Transfer-Encoding:Content-Type:MIME-Version:From; bh=A874jRM+JuyBHXdJiKm1Rbp+44N3dVhe2nB49IAhQHc=; b=XwVY9wb8pFcdf6xYY2XM8Aiv+F MrE86WX+6yjGR9Qi4Uodg/j6Z4WHlRP2m+CqkThZI37EJLnWStXvl+oaxjRN8SMIM8Vc3ClMok5cW r8tSXtGbGjf9p9XfPpd/M5xTCxUjhE+7jsnmQIwScgLXBw7iCZiVkPMWEyxXDmPrhS0A=; From: Ian Jackson MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <24602.56402.42441.687037@mariner.uk.xensource.com> Date: Wed, 3 Feb 2021 17:24:34 +0000 To: Manuel Bouyer Cc: xen-devel@lists.xenproject.org, Wei Liu , Juergen Gross Subject: Re: [PATCH] xenstored: close socket connections on error In-Reply-To: <20210203165421.1550-2-bouyer@netbsd.org> References: <20210203165421.1550-1-bouyer@netbsd.org> <20210203165421.1550-2-bouyer@netbsd.org> X-Mailer: VM 8.2.0b under 24.5.1 (i686-pc-linux-gnu) Manuel Bouyer writes ("[PATCH] xenstored: close socket connections on error"): > On error, don't keep socket connection in ignored state but close them. > When the remote end of a socket is closed, xenstored will flag it as an > error and switch the connection to ignored. But on some OSes (e.g. > NetBSD), poll(2) will return only POLLIN in this case, so sockets in ignored > state will stay open forever in xenstored (and it will loop with CPU 100% > busy). Juergen, I think you probably know this code the best. Would you be able to review this ? I'm not sure I understand what the specific behaviour on NetBSD is that is upsetting xenstored. Or rather, what it is that xenstored is using to tell when the socket should be closed. I grepped for POLLERR and nothing came up. Or to put it another way, is this commit > Fixes: d2fa370d3ef9cbe22d7256c608671cdcdf6e0083 broken on Linux too ? Ian.