From patchwork Mon Dec 13 10:10:48 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Garry X-Patchwork-Id: 523862 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7E74CC433F5 for ; Mon, 13 Dec 2021 10:18:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237671AbhLMKSU (ORCPT ); Mon, 13 Dec 2021 05:18:20 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4252 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236522AbhLMKQQ (ORCPT ); Mon, 13 Dec 2021 05:16:16 -0500 Received: from fraeml701-chm.china.huawei.com (unknown [172.18.147.201]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JCHNn12mrz67x9d; Mon, 13 Dec 2021 18:11:53 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml701-chm.china.huawei.com (10.206.15.50) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2308.20; Mon, 13 Dec 2021 11:16:13 +0100 Received: from localhost.localdomain (10.69.192.58) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Mon, 13 Dec 2021 10:16:09 +0000 From: John Garry To: , , CC: , , , , , John Garry Subject: [PATCH v3] scsi: pm8001: Fix phys_to_virt() usage on dma_addr_t Date: Mon, 13 Dec 2021 18:10:48 +0800 Message-ID: <1639390248-213603-1-git-send-email-john.garry@huawei.com> X-Mailer: git-send-email 2.8.1 MIME-Version: 1.0 X-Originating-IP: [10.69.192.58] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org The driver supports a "direct" mode of operation, where the SMP req frame is directly copied into the command payload (and vice-versa for the SMP resp). To get at the SMP req frame data in the scatterlist the driver uses phys_to_virt() on the DMA mapped memory dma_addr_t . This is broken, and subsequently crashes as follows when an IOMMU is enabled: Unable to handle kernel paging request at virtual address ffff0000fcebfb00 ... pc : pm80xx_chip_smp_req+0x2d0/0x3d0 lr : pm80xx_chip_smp_req+0xac/0x3d0 pm80xx_chip_smp_req+0x2d0/0x3d0 pm8001_task_exec.constprop.0+0x368/0x520 pm8001_queue_command+0x1c/0x30 smp_execute_task_sg+0xdc/0x204 sas_discover_expander.part.0+0xac/0x6cc sas_discover_root_expander+0x8c/0x150 sas_discover_domain+0x3ac/0x6a0 process_one_work+0x1d0/0x354 worker_thread+0x13c/0x470 kthread+0x17c/0x190 ret_from_fork+0x10/0x20 Code: 371806e1 910006d6 6b16033f 54000249 (38766b05) ---[ end trace b91d59aaee98ea2d ]--- note: kworker/u192:0[7] exited with preempt_count 1 Instead use kmap_atomic(). Signed-off-by: John Garry --- Difference to v1: - use kmap_atomic() in both locations Difference to v2: - add whitespace around arithmetic (Damien) diff --git a/drivers/scsi/pm8001/pm80xx_hwi.c b/drivers/scsi/pm8001/pm80xx_hwi.c index b9f6d83ff380..2101fc5761c3 100644 --- a/drivers/scsi/pm8001/pm80xx_hwi.c +++ b/drivers/scsi/pm8001/pm80xx_hwi.c @@ -3053,7 +3053,6 @@ mpi_smp_completion(struct pm8001_hba_info *pm8001_ha, void *piomb) struct smp_completion_resp *psmpPayload; struct task_status_struct *ts; struct pm8001_device *pm8001_dev; - char *pdma_respaddr = NULL; psmpPayload = (struct smp_completion_resp *)(piomb + 4); status = le32_to_cpu(psmpPayload->status); @@ -3080,19 +3079,23 @@ mpi_smp_completion(struct pm8001_hba_info *pm8001_ha, void *piomb) if (pm8001_dev) atomic_dec(&pm8001_dev->running_req); if (pm8001_ha->smp_exp_mode == SMP_DIRECT) { + struct scatterlist *sg_resp = &t->smp_task.smp_resp; + u8 *payload; + void *to; + pm8001_dbg(pm8001_ha, IO, "DIRECT RESPONSE Length:%d\n", param); - pdma_respaddr = (char *)(phys_to_virt(cpu_to_le64 - ((u64)sg_dma_address - (&t->smp_task.smp_resp)))); + to = kmap_atomic(sg_page(sg_resp)); + payload = to + sg_resp->offset; for (i = 0; i < param; i++) { - *(pdma_respaddr+i) = psmpPayload->_r_a[i]; + *(payload + i) = psmpPayload->_r_a[i]; pm8001_dbg(pm8001_ha, IO, "SMP Byte%d DMA data 0x%x psmp 0x%x\n", - i, *(pdma_respaddr + i), + i, *(payload + i), psmpPayload->_r_a[i]); } + kunmap_atomic(to); } break; case IO_ABORTED: @@ -4236,14 +4239,14 @@ static int pm80xx_chip_smp_req(struct pm8001_hba_info *pm8001_ha, struct sas_task *task = ccb->task; struct domain_device *dev = task->dev; struct pm8001_device *pm8001_dev = dev->lldd_dev; - struct scatterlist *sg_req, *sg_resp; + struct scatterlist *sg_req, *sg_resp, *smp_req; u32 req_len, resp_len; struct smp_req smp_cmd; u32 opc; struct inbound_queue_table *circularQ; - char *preq_dma_addr = NULL; - __le64 tmp_addr; u32 i, length; + u8 *payload; + u8 *to; memset(&smp_cmd, 0, sizeof(smp_cmd)); /* @@ -4280,8 +4283,9 @@ static int pm80xx_chip_smp_req(struct pm8001_hba_info *pm8001_ha, pm8001_ha->smp_exp_mode = SMP_INDIRECT; - tmp_addr = cpu_to_le64((u64)sg_dma_address(&task->smp_task.smp_req)); - preq_dma_addr = (char *)phys_to_virt(tmp_addr); + smp_req = &task->smp_task.smp_req; + to = kmap_atomic(sg_page(smp_req)); + payload = to + smp_req->offset; /* INDIRECT MODE command settings. Use DMA */ if (pm8001_ha->smp_exp_mode == SMP_INDIRECT) { @@ -4289,7 +4293,7 @@ static int pm80xx_chip_smp_req(struct pm8001_hba_info *pm8001_ha, /* for SPCv indirect mode. Place the top 4 bytes of * SMP Request header here. */ for (i = 0; i < 4; i++) - smp_cmd.smp_req16[i] = *(preq_dma_addr + i); + smp_cmd.smp_req16[i] = *(payload + i); /* exclude top 4 bytes for SMP req header */ smp_cmd.long_smp_req.long_req_addr = cpu_to_le64((u64)sg_dma_address @@ -4320,20 +4324,20 @@ static int pm80xx_chip_smp_req(struct pm8001_hba_info *pm8001_ha, pm8001_dbg(pm8001_ha, IO, "SMP REQUEST DIRECT MODE\n"); for (i = 0; i < length; i++) if (i < 16) { - smp_cmd.smp_req16[i] = *(preq_dma_addr+i); + smp_cmd.smp_req16[i] = *(payload + i); pm8001_dbg(pm8001_ha, IO, "Byte[%d]:%x (DMA data:%x)\n", i, smp_cmd.smp_req16[i], - *(preq_dma_addr)); + *(payload)); } else { - smp_cmd.smp_req[i] = *(preq_dma_addr+i); + smp_cmd.smp_req[i] = *(payload + i); pm8001_dbg(pm8001_ha, IO, "Byte[%d]:%x (DMA data:%x)\n", i, smp_cmd.smp_req[i], - *(preq_dma_addr)); + *(payload)); } } - + kunmap_atomic(to); build_smp_cmd(pm8001_dev->device_id, smp_cmd.tag, &smp_cmd, pm8001_ha->smp_exp_mode, length); rc = pm8001_mpi_build_cmd(pm8001_ha, circularQ, opc, &smp_cmd,