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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,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 1C29DCA9EAF for ; Sun, 27 Oct 2019 21:14:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E006B214E0 for ; Sun, 27 Oct 2019 21:14:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572210881; bh=1xnmcLQJuvAucRr4+JBzuh6E6nUsMI+yUdoL4DunbeA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=GZybEJMt9aQ1zdA8m0KIWVbaQLaeyY7nrTgq50IC26wDBRNNESnb4uPg+I1yZPkbM Tf2aYRBHvlXMYfR8nZBfLhfrzThL9YRDQNMubNRWVPx2mdf5MCzliFOL+bM4LqnlFi 9VcAQh77aidwZ7PrRllvjrC1SwEtSdnY4Dpe9rsg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730490AbfJ0VOj (ORCPT ); Sun, 27 Oct 2019 17:14:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:33624 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730483AbfJ0VOi (ORCPT ); Sun, 27 Oct 2019 17:14:38 -0400 Received: from localhost (100.50.158.77.rev.sfr.net [77.158.50.100]) (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 7A7A1205C9; Sun, 27 Oct 2019 21:14:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572210878; bh=1xnmcLQJuvAucRr4+JBzuh6E6nUsMI+yUdoL4DunbeA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=n5xpmbaG/nVloVKKL/IkGXqyo6OVXXH4p5wJHmYPU62dGKTE6q9eakOFkh9gDpb+b sduYhRGs4e5/uUS1h0q15gDb0Sc9fbys7Xm8iDwZO1ldSX5TwYDC8Fh/dDlV/EnR1u mivOIqKK44FckSw+Tvv9btJ6ViJOSai2Skwsz9CU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jens Remus , Benjamin Block , Steffen Maier , "Martin K. Petersen" Subject: [PATCH 4.19 48/93] scsi: zfcp: fix reaction on bit error threshold notification Date: Sun, 27 Oct 2019 22:01:00 +0100 Message-Id: <20191027203300.360392635@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191027203251.029297948@linuxfoundation.org> References: <20191027203251.029297948@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Steffen Maier commit 2190168aaea42c31bff7b9a967e7b045f07df095 upstream. On excessive bit errors for the FCP channel ingress fibre path, the channel notifies us. Previously, we only emitted a kernel message and a trace record. Since performance can become suboptimal with I/O timeouts due to bit errors, we now stop using an FCP device by default on channel notification so multipath on top can timely failover to other paths. A new module parameter zfcp.ber_stop can be used to get zfcp old behavior. User explanation of new kernel message: * Description: * The FCP channel reported that its bit error threshold has been exceeded. * These errors might result from a problem with the physical components * of the local fibre link into the FCP channel. * The problem might be damage or malfunction of the cable or * cable connection between the FCP channel and * the adjacent fabric switch port or the point-to-point peer. * Find details about the errors in the HBA trace for the FCP device. * The zfcp device driver closed down the FCP device * to limit the performance impact from possible I/O command timeouts. * User action: * Check for problems on the local fibre link, ensure that fibre optics are * clean and functional, and all cables are properly plugged. * After the repair action, you can manually recover the FCP device by * writing "0" into its "failed" sysfs attribute. * If recovery through sysfs is not possible, set the CHPID of the device * offline and back online on the service element. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: #2.6.30+ Link: https://lore.kernel.org/r/20191001104949.42810-1-maier@linux.ibm.com Reviewed-by: Jens Remus Reviewed-by: Benjamin Block Signed-off-by: Steffen Maier Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman --- drivers/s390/scsi/zfcp_fsf.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) --- a/drivers/s390/scsi/zfcp_fsf.c +++ b/drivers/s390/scsi/zfcp_fsf.c @@ -21,6 +21,11 @@ struct kmem_cache *zfcp_fsf_qtcb_cache; +static bool ber_stop = true; +module_param(ber_stop, bool, 0600); +MODULE_PARM_DESC(ber_stop, + "Shuts down FCP devices for FCP channels that report a bit-error count in excess of its threshold (default on)"); + static void zfcp_fsf_request_timeout_handler(struct timer_list *t) { struct zfcp_fsf_req *fsf_req = from_timer(fsf_req, t, timer); @@ -230,10 +235,15 @@ static void zfcp_fsf_status_read_handler case FSF_STATUS_READ_SENSE_DATA_AVAIL: break; case FSF_STATUS_READ_BIT_ERROR_THRESHOLD: - dev_warn(&adapter->ccw_device->dev, - "The error threshold for checksum statistics " - "has been exceeded\n"); zfcp_dbf_hba_bit_err("fssrh_3", req); + if (ber_stop) { + dev_warn(&adapter->ccw_device->dev, + "All paths over this FCP device are disused because of excessive bit errors\n"); + zfcp_erp_adapter_shutdown(adapter, 0, "fssrh_b"); + } else { + dev_warn(&adapter->ccw_device->dev, + "The error threshold for checksum statistics has been exceeded\n"); + } break; case FSF_STATUS_READ_LINK_DOWN: zfcp_fsf_status_read_link_down(req);