From 327f242fa806c199a183c2197592e94d336c8266 Mon Sep 17 00:00:00 2001 From: Xiaofei Tan Date: Sat, 24 Mar 2018 00:05:13 +0800 Subject: [PATCH] scsi: hisi_sas: check IPTT is valid before using it for v3 hw 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 adds a check of IPTT in cq_tasklet_v3_hw() and discards 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 Signed-off-by: Martin K. Petersen --- 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 efe64bcfa4f2..aa52d5e424f7 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; -- 2.11.0