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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_RED, 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 02C02C433E6 for ; Mon, 28 Dec 2020 15:34:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C3B0622475 for ; Mon, 28 Dec 2020 15:34:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2408514AbgL1Pea (ORCPT ); Mon, 28 Dec 2020 10:34:30 -0500 Received: from mail.kernel.org ([198.145.29.99]:56240 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2407425AbgL1NyU (ORCPT ); Mon, 28 Dec 2020 08:54:20 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 87605207B2; Mon, 28 Dec 2020 13:53:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1609163620; bh=68WcUA4SCIq5euYBlkcE9hSO8wqkCfcl9VXdHARhno0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rWPPKWM0mRgpAd/jca+R2iSEaEuBwirvX8wMP5Y+zsRrpEADqDb2SCJOGk+KqQ7b1 0VkZ+GoQjicF24/hB5Q7c0mZEqDzd801lM9NcUqbMcnHmTztKwid4BcYhVlNTgz3mR v+vrmlBwsUrNHW6tBPDJQrW52BDlGaPdWF0YRAXs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Stefan Haberland , Jan Hoeppner , Jens Axboe Subject: [PATCH 5.4 350/453] s390/dasd: prevent inconsistent LCU device data Date: Mon, 28 Dec 2020 13:49:46 +0100 Message-Id: <20201228124954.052404902@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201228124937.240114599@linuxfoundation.org> References: <20201228124937.240114599@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Stefan Haberland commit a29ea01653493b94ea12bb2b89d1564a265081b6 upstream. Prevent _lcu_update from adding a device to a pavgroup if the LCU still requires an update. The data is not reliable any longer and in parallel devices might have been moved on the lists already. This might lead to list corruptions or invalid PAV grouping. Only add devices to a pavgroup if the LCU is up to date. Additional steps are taken by the scheduled lcu update. Fixes: 8e09f21574ea ("[S390] dasd: add hyper PAV support to DASD device driver, part 1") Cc: stable@vger.kernel.org Signed-off-by: Stefan Haberland Reviewed-by: Jan Hoeppner Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- drivers/s390/block/dasd_alias.c | 9 +++++++++ 1 file changed, 9 insertions(+) --- a/drivers/s390/block/dasd_alias.c +++ b/drivers/s390/block/dasd_alias.c @@ -511,6 +511,14 @@ static int _lcu_update(struct dasd_devic return rc; spin_lock_irqsave(&lcu->lock, flags); + /* + * there is another update needed skip the remaining handling + * the data might already be outdated + * but especially do not add the device to an LCU with pending + * update + */ + if (lcu->flags & NEED_UAC_UPDATE) + goto out; lcu->pav = NO_PAV; for (i = 0; i < MAX_DEVICES_PER_LCU; ++i) { switch (lcu->uac->unit[i].ua_type) { @@ -529,6 +537,7 @@ static int _lcu_update(struct dasd_devic alias_list) { _add_device_to_lcu(lcu, device, refdev); } +out: spin_unlock_irqrestore(&lcu->lock, flags); return 0; }