From patchwork Fri Sep 8 15:24:43 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Halil Pasic X-Patchwork-Id: 811649 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3xph3S0CsYz9sBZ for ; Sat, 9 Sep 2017 01:25:38 +1000 (AEST) Received: from localhost ([::1]:45949 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dqLA0-0000bn-H7 for incoming@patchwork.ozlabs.org; Fri, 08 Sep 2017 11:25:36 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44057) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dqL9T-0000bA-Ek for qemu-devel@nongnu.org; Fri, 08 Sep 2017 11:25:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dqL9O-0004of-Ez for qemu-devel@nongnu.org; Fri, 08 Sep 2017 11:25:03 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:45748 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dqL9O-0004nj-8q for qemu-devel@nongnu.org; Fri, 08 Sep 2017 11:24:58 -0400 Received: from pps.filterd (m0098421.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v88FO09h032292 for ; Fri, 8 Sep 2017 11:24:55 -0400 Received: from e06smtp10.uk.ibm.com (e06smtp10.uk.ibm.com [195.75.94.106]) by mx0a-001b2d01.pphosted.com with ESMTP id 2cuvvtb7gr-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Fri, 08 Sep 2017 11:24:54 -0400 Received: from localhost by e06smtp10.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Fri, 8 Sep 2017 16:24:52 +0100 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps4076.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v88FOpdT16187424; Fri, 8 Sep 2017 15:24:51 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 9DE74AE04D; Fri, 8 Sep 2017 16:20:03 +0100 (BST) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 6812BAE045; Fri, 8 Sep 2017 16:20:03 +0100 (BST) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTPS; Fri, 8 Sep 2017 16:20:03 +0100 (BST) From: Halil Pasic To: Cornelia Huck Date: Fri, 8 Sep 2017 17:24:43 +0200 X-Mailer: git-send-email 2.13.5 In-Reply-To: <20170908152446.14606-1-pasic@linux.vnet.ibm.com> References: <20170908152446.14606-1-pasic@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 17090815-0040-0000-0000-000003D89607 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17090815-0041-0000-0000-000025D99C77 Message-Id: <20170908152446.14606-2-pasic@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-09-08_10:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1707230000 definitions=main-1709080231 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] [fuzzy] X-Received-From: 148.163.158.5 Subject: [Qemu-devel] [PATCH 1/4] s390x/css: drop data-check in interpretation X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Dong Jia Shi , Halil Pasic , Pierre Morel , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" The architecture says that channel-data check is indicating that an uncorrected storage (memory) error has been detected in regard to the data residing in main storage (memory) that is currently used for an I/O operation. The described detection is done using the CBC technology. The ccw interpretation code is however generating a channel-data check effectively when the (device specific) ccw_cb returns -EFAULT. In case of virtio-ccw devices this happens when mapping memory fails, or when a NULL pointer is encountered. So this behavior is not architecture conform. Furthermore the best fit for these situations (null pointer, mapping a piece of guest memory fails) from architectural perspective the condition described as the channel subsystem refers to a location that is not available, which when encountered shall result in a channel-program check. To fix this, all we have to do is to get rid of the switch case matching -EFAULT: the default is generating a channel-program check. --- Was posted as stand alone patch. See: http://patchwork.ozlabs.org/patch/810995/ If you are going to, *please review there*. Signed-off-by: Halil Pasic --- hw/s390x/css.c | 9 --------- 1 file changed, 9 deletions(-) diff --git a/hw/s390x/css.c b/hw/s390x/css.c index 901dc6a0f3..09f6ba0310 100644 --- a/hw/s390x/css.c +++ b/hw/s390x/css.c @@ -980,15 +980,6 @@ static void sch_handle_start_func_virtual(SubchDev *sch) SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND; s->cpa = sch->channel_prog + 8; break; - case -EFAULT: - /* memory problem, generate channel data check */ - s->ctrl &= ~SCSW_ACTL_START_PEND; - s->cstat = SCSW_CSTAT_DATA_CHECK; - s->ctrl &= ~SCSW_CTRL_MASK_STCTL; - s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY | - SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND; - s->cpa = sch->channel_prog + 8; - break; case -EBUSY: /* subchannel busy, generate deferred cc 1 */ s->flags &= ~SCSW_FLAGS_MASK_CC;