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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 A1CA8C43381 for ; Mon, 25 Feb 2019 21:30:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7220421841 for ; Mon, 25 Feb 2019 21:30:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1551130257; bh=krCwKfAqpzUK2lgHTCHmcqmRZNtYnvJiykOSssSGQT0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=YqGcxDpQvlIkP9IFBwMGA7tfuhHVsZeH7a1AiVwIuUf565oQWpBmoM3ECQD7qBS84 dUOV5eK/MYjy2l7OWOak8ogVYfcAz/lYgomU3DxKgKMOsiCGhKa0Z5Ez9m4zhAiLZM xmEEATgWXpCIp8SO+f0XGFz7MAZwD/AmLBJEcf0k= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732015AbfBYVa4 (ORCPT ); Mon, 25 Feb 2019 16:30:56 -0500 Received: from mail.kernel.org ([198.145.29.99]:36498 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732019AbfBYVaw (ORCPT ); Mon, 25 Feb 2019 16:30:52 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CEDE921848; Mon, 25 Feb 2019 21:30:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1551130252; bh=krCwKfAqpzUK2lgHTCHmcqmRZNtYnvJiykOSssSGQT0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=q2KgDwiF4wfz483aPx4dHW4ETiMefS/Un+as3zh7B22StAiPQ75xHDE03VqhyXtZI gZtaj4CEqy+95vIPrOISUCvcG5lzzm3v8pCwyX4wgRd7OZQsieNJR38+DXwCeu6zWo YSWoU5hNHXD0dKfDu79yS6xOVst9xiD4kKvMtczs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Stefano Stabellini , Boris Ostrovsky , Sasha Levin Subject: [PATCH 4.20 024/183] pvcalls-back: set -ENOTCONN in pvcalls_conn_back_read Date: Mon, 25 Feb 2019 22:09:57 +0100 Message-Id: <20190225195058.791937642@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190225195054.748060397@linuxfoundation.org> References: <20190225195054.748060397@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.20-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit e6587cdbd732eacb4c7ce592ed46f7bbcefb655f ] When a connection is closing we receive on pvcalls_sk_state_change notification. Instead of setting the connection as closed immediately (-ENOTCONN), let's read one more time from it: pvcalls_conn_back_read will set the connection as closed when necessary. That way, we avoid races between pvcalls_sk_state_change and pvcalls_back_ioworker. Signed-off-by: Stefano Stabellini Reviewed-by: Boris Ostrovsky Signed-off-by: Boris Ostrovsky Signed-off-by: Sasha Levin --- drivers/xen/pvcalls-back.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/xen/pvcalls-back.c b/drivers/xen/pvcalls-back.c index 2e5d845b50914..71b628774c6fb 100644 --- a/drivers/xen/pvcalls-back.c +++ b/drivers/xen/pvcalls-back.c @@ -160,9 +160,10 @@ static void pvcalls_conn_back_read(void *opaque) /* write the data, then modify the indexes */ virt_wmb(); - if (ret < 0) + if (ret < 0) { + atomic_set(&map->read, 0); intf->in_error = ret; - else + } else intf->in_prod = prod + ret; /* update the indexes, then notify the other end */ virt_wmb(); @@ -288,7 +289,7 @@ static void pvcalls_sk_state_change(struct sock *sock) return; intf = map->ring; - intf->in_error = -ENOTCONN; + atomic_inc(&map->read); notify_remote_via_irq(map->irq); } -- 2.19.1