From patchwork Wed May 17 19:35:40 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeffrey Hugo X-Patchwork-Id: 13245626 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 58618C77B75 for ; Wed, 17 May 2023 19:36:24 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A12F110E469; Wed, 17 May 2023 19:36:21 +0000 (UTC) Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) by gabe.freedesktop.org (Postfix) with ESMTPS id 5F43110E285 for ; Wed, 17 May 2023 19:36:18 +0000 (UTC) Received: from pps.filterd (m0279869.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 34HJ85C7009230; Wed, 17 May 2023 19:36:14 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=qcppdkim1; bh=3CvJjTFDBBGbjsEpRMixb/b2QnSDoZ7DAlJA0PNNj9k=; b=ct4i+An4RBTDJfLoS8lzW8CV2g8uquwYWUx2O+rgtI3DUbOdpLrKTc/ESQzYgwAIfzKc vDq42VdhTuDwhxgnj6qMxJWKCMMjeIKAacwGj9CpZvu+kJCHfpew7mdpttABPCiMSVzv nSfMpK+2YBMwn0QQdt+Os/zsaYCWBYCBI1mYCLwHiNrmLAD3dYuqPZDQvHMSVMGslarU VC0NF97dCeFRLxbdG8QFQNY/ui6omI8eB2QoYF6rVpZTpDP4DQfyRwxXk0c8Xr1WA3b+ H8Y1lhhFqlrlAJZHJ8xj7aq+hV4ZQ+VyhMHKo6WnGhplRvKYJrZ82A4bevExc5FjUNnB RQ== Received: from nalasppmta01.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3qmxyp10gr-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 17 May 2023 19:36:13 +0000 Received: from nalasex01a.na.qualcomm.com (nalasex01a.na.qualcomm.com [10.47.209.196]) by NALASPPMTA01.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 34HJaDtW031222 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 17 May 2023 19:36:13 GMT Received: from jhugo-lnx.qualcomm.com (10.80.80.8) by nalasex01a.na.qualcomm.com (10.47.209.196) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.42; Wed, 17 May 2023 12:36:12 -0700 From: Jeffrey Hugo To: , , , , , Subject: [PATCH 5/5] accel/qaic: Fix NNC message corruption Date: Wed, 17 May 2023 13:35:40 -0600 Message-ID: <20230517193540.14323-6-quic_jhugo@quicinc.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230517193540.14323-1-quic_jhugo@quicinc.com> References: <20230517193540.14323-1-quic_jhugo@quicinc.com> MIME-Version: 1.0 X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) To nalasex01a.na.qualcomm.com (10.47.209.196) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-ORIG-GUID: 8NB7hlq_CWI09biYXn4AEfAZpFEat7bf X-Proofpoint-GUID: 8NB7hlq_CWI09biYXn4AEfAZpFEat7bf X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.957,Hydra:6.0.573,FMLib:17.11.170.22 definitions=2023-05-17_04,2023-05-17_02,2023-02-09_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=999 priorityscore=1501 impostorscore=0 suspectscore=0 mlxscore=0 bulkscore=0 adultscore=0 lowpriorityscore=0 spamscore=0 clxscore=1015 malwarescore=0 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2304280000 definitions=main-2305170162 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arm-msm@vger.kernel.org, Jeffrey Hugo , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" If msg_xfer() is unable to queue part of a NNC message because the MHI ring is full, it will attempt to give the QSM some time to drain the queue. However, if QSM fails to make any room, msg_xfer() will fail and tell the caller to try again. This is problematic because part of the message may have been committed to the ring and there is no mechanism to revoke that content. This will cause QSM to receive a corrupt message. The better way to do this is to check if the ring has enough space for the entire message before committing any of the message. Since msg_xfer() is under the cntl_mutex no one else can come in and consume the space. Fixes: 129776ac2e38 ("accel/qaic: Add control path") Signed-off-by: Jeffrey Hugo Reviewed-by: Pranjal Ramajor Asha Kanojiya Reviewed-by: Carl Vanderlip --- drivers/accel/qaic/qaic_control.c | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-) diff --git a/drivers/accel/qaic/qaic_control.c b/drivers/accel/qaic/qaic_control.c index 9e39b1a324f7..5c57f7b4494e 100644 --- a/drivers/accel/qaic/qaic_control.c +++ b/drivers/accel/qaic/qaic_control.c @@ -997,14 +997,34 @@ static void *msg_xfer(struct qaic_device *qdev, struct wrapper_list *wrappers, u struct xfer_queue_elem elem; struct wire_msg *out_buf; struct wrapper_msg *w; + long ret = -EAGAIN; + int xfer_count = 0; int retry_count; - long ret; if (qdev->in_reset) { mutex_unlock(&qdev->cntl_mutex); return ERR_PTR(-ENODEV); } + /* Attempt to avoid a partial commit of a message */ + list_for_each_entry(w, &wrappers->list, list) + xfer_count++; + + for (retry_count = 0; retry_count < QAIC_MHI_RETRY_MAX; retry_count++) { + if (xfer_count <= mhi_get_free_desc_count(qdev->cntl_ch, DMA_TO_DEVICE)) { + ret = 0; + break; + } + msleep_interruptible(QAIC_MHI_RETRY_WAIT_MS); + if (signal_pending(current)) + break; + } + + if (ret) { + mutex_unlock(&qdev->cntl_mutex); + return ERR_PTR(ret); + } + elem.seq_num = seq_num; elem.buf = NULL; init_completion(&elem.xfer_done); @@ -1038,16 +1058,9 @@ static void *msg_xfer(struct qaic_device *qdev, struct wrapper_list *wrappers, u list_for_each_entry(w, &wrappers->list, list) { kref_get(&w->ref_count); retry_count = 0; -retry: ret = mhi_queue_buf(qdev->cntl_ch, DMA_TO_DEVICE, &w->msg, w->len, list_is_last(&w->list, &wrappers->list) ? MHI_EOT : MHI_CHAIN); if (ret) { - if (ret == -EAGAIN && retry_count++ < QAIC_MHI_RETRY_MAX) { - msleep_interruptible(QAIC_MHI_RETRY_WAIT_MS); - if (!signal_pending(current)) - goto retry; - } - qdev->cntl_lost_buf = true; kref_put(&w->ref_count, free_wrapper); mutex_unlock(&qdev->cntl_mutex);