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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,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 D512DC282CE for ; Wed, 13 Feb 2019 03:06:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 99C48207E0 for ; Wed, 13 Feb 2019 03:06:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550027171; bh=Lt1+69nmdEZAXEvrcmqZJ8nB/oNvhF9tB2778vCUFgs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=CKJ9mYmagap/0C7wO+55PM08SWUaNuIM8sERrajq14FPzlU7b8hMC3ET40JhSeXEv G6Zzk257U0MQtvzTwgB+yC9js0ETRuu1DU4Rz/39NveAFZgZ8OKOg4fs/zL1Gkujub +HsyhPjUyHeVz0eZcHV8pWauD+acAl4jnOhyKbo4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387462AbfBMCdq (ORCPT ); Tue, 12 Feb 2019 21:33:46 -0500 Received: from mail.kernel.org ([198.145.29.99]:37292 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731487AbfBMCdo (ORCPT ); Tue, 12 Feb 2019 21:33:44 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9D818222C2; Wed, 13 Feb 2019 02:33:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550025223; bh=Lt1+69nmdEZAXEvrcmqZJ8nB/oNvhF9tB2778vCUFgs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ozNxsRuUdrHIsSGIeIBSfe2FAR40xagN8BCUvT62keVqJS7j7WwX2j0SfBC95XYd7 /4V86D5A4qytpJ57Zh9SFc8/BH490H+oPy1kaN8ZcRaDCGZsKt/lUFMdqo34nQGz7I tvSEq4n2dX/vTbH0EkRN6swzheP6cNYGgeeSLZKE= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Stefano Stabellini , Stefano Stabellini , Boris Ostrovsky , Sasha Levin Subject: [PATCH AUTOSEL 4.20 006/105] pvcalls-back: set -ENOTCONN in pvcalls_conn_back_read Date: Tue, 12 Feb 2019 21:31:57 -0500 Message-Id: <20190213023336.19019-6-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190213023336.19019-1-sashal@kernel.org> References: <20190213023336.19019-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Stefano Stabellini [ 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 2e5d845b5091..71b628774c6f 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