From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752309AbeCWQGQ (ORCPT ); Fri, 23 Mar 2018 12:06:16 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:6685 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752229AbeCWQGO (ORCPT ); Fri, 23 Mar 2018 12:06:14 -0400 From: John Garry To: , CC: , , , Xiaofei Tan , "John Garry" Subject: [PATCH 6/8] scsi: hisi_sas: check IPTT is valid before using it for v3 hw Date: Sat, 24 Mar 2018 00:05:13 +0800 Message-ID: <1521821115-120040-7-git-send-email-john.garry@huawei.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1521821115-120040-1-git-send-email-john.garry@huawei.com> References: <1521821115-120040-1-git-send-email-john.garry@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.67.212.75] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Xiaofei Tan There is a bug of v3 hw development version. When AXI error happen, hw may return an abnormal CQ that IPTT value is 0xffff. This will cause IPTT out-of-bounds reference. This patch add an check of IPTT in cq_tasklet_v3_hw(), and discard invalid slot. This workaround scheme is just to enhance fault-tolerance of the driver. So, we will apply this scheme for all version of v3 hw, although release version has fixed this SoC bug. Signed-off-by: Xiaofei Tan Signed-off-by: John Garry --- drivers/scsi/hisi_sas/hisi_sas_v3_hw.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c index efe64bc..aa52d5e 100644 --- a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c +++ b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c @@ -1731,15 +1731,19 @@ static void cq_tasklet_v3_hw(unsigned long val) while (rd_point != wr_point) { struct hisi_sas_complete_v3_hdr *complete_hdr; + struct device *dev = hisi_hba->dev; int iptt; complete_hdr = &complete_queue[rd_point]; iptt = (complete_hdr->dw1) & CMPLT_HDR_IPTT_MSK; - slot = &hisi_hba->slot_info[iptt]; - slot->cmplt_queue_slot = rd_point; - slot->cmplt_queue = queue; - slot_complete_v3_hw(hisi_hba, slot); + if (likely(iptt < HISI_SAS_COMMAND_ENTRIES_V3_HW)) { + slot = &hisi_hba->slot_info[iptt]; + slot->cmplt_queue_slot = rd_point; + slot->cmplt_queue = queue; + slot_complete_v3_hw(hisi_hba, slot); + } else + dev_err(dev, "IPTT %d is invalid, discard it.\n", iptt); if (++rd_point >= HISI_SAS_QUEUE_SLOTS) rd_point = 0; -- 1.9.1