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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 64C67C433F5 for ; Wed, 20 Oct 2021 15:45:43 +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 2B419610E6 for ; Wed, 20 Oct 2021 15:45:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 2B419610E6 Authentication-Results: mail.kernel.org; dmarc=pass (p=none dis=none) header.from=xenproject.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.213997.372393 (Exim 4.92) (envelope-from ) id 1mdDmO-00037s-Da; Wed, 20 Oct 2021 15:45:24 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 213997.372393; Wed, 20 Oct 2021 15:45:24 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1mdDmO-00037l-Ag; Wed, 20 Oct 2021 15:45:24 +0000 Received: by outflank-mailman (input) for mailman id 213997; Wed, 20 Oct 2021 15:45:23 +0000 Received: from mail.xenproject.org ([104.130.215.37]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1mdDmN-00037f-Ki for xen-devel@lists.xenproject.org; Wed, 20 Oct 2021 15:45:23 +0000 Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1mdDmN-0008SW-Fy for xen-devel@lists.xenproject.org; Wed, 20 Oct 2021 15:45:23 +0000 Received: from iwj (helo=mariner.uk.xensource.com) by xenbits.xenproject.org with local-bsmtp (Exim 4.92) (envelope-from ) id 1mdDmN-0001Df-Et for xen-devel@lists.xenproject.org; Wed, 20 Oct 2021 15:45:23 +0000 Received: from iwj by mariner.uk.xensource.com with local (Exim 4.89) (envelope-from ) id 1mdDmJ-0004If-UX; Wed, 20 Oct 2021 16:45:20 +0100 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=jcjgEwRsGmmjSzP3LNYUdjU7tG4+MlDKfHG44Xp3RFw=; b=cZ99fqUh4tWDwI+VkzhCkz0W4Q NyDzBATF4o54dVn8z4iJaD2Ys+ZtZX8Pp8TqF/wyqYFb9bRp+RKfn5cqG5VA6a+QXZne+PJFkciG5 K7G/9uNkvp6cu3Sm+sV80AxCkBHQKOXDAYu3lpf5oT+GB098V1vltwqi2pd3wrUHWWf0=; From: Ian Jackson MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <24944.14735.525284.612126@mariner.uk.xensource.com> Date: Wed, 20 Oct 2021 16:45:19 +0100 To: Julien Grall Cc: xen-devel@lists.xenproject.org, Julien Grall , Ian Jackson , Wei Liu , Juergen Gross Subject: Re: [PATCH for-4.16] tools/xenstored: Ignore domain we were unable to restore In-Reply-To: <20211020144519.10362-1-julien@xen.org> References: <20211020144519.10362-1-julien@xen.org> X-Mailer: VM 8.2.0b under 24.5.1 (i686-pc-linux-gnu) Julien Grall writes ("[PATCH for-4.16] tools/xenstored: Ignore domain we were unable to restore"): > From: Julien Grall > > Commit 939775cfd3 "handle dying domains in live update" was meant to > handle gracefully dying domain. However, the @releaseDomain watch > will end up to be sent as soon as we finished to restore Xenstored > state. > > This may be before Xen reports the domain to be dying (such as if > the guest decided to revoke access to the xenstore page). Consequently > daemon like xenconsoled will not clean-up the domain and it will be > left as a zombie. > > To avoid the problem, mark the connection as ignored. This also > requires to tweak conn_can_write() and conn_can_read() to prevent > dereferencing a NULL pointer (the interface will not mapped). > > The check conn->is_ignored was originally added after the callbacks > because the helpers for a socket connection may close the fd. However, > ignore_connection() will close a socket connection directly. So it is > fine to do the re-order. Release-Acked-by: Ian Jackson