From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Rood Subject: [PATCH 8/8] pm80xx: avoid a panic if MSI(X) interrupts are disabled Date: Fri, 30 Oct 2015 10:53:31 -0400 Message-ID: <1446216811-2248-9-git-send-email-brood@attotech.com> References: <1446216811-2248-1-git-send-email-brood@attotech.com> Return-path: Received: from mail-qg0-f53.google.com ([209.85.192.53]:33874 "EHLO mail-qg0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758949AbbJ3Oxq (ORCPT ); Fri, 30 Oct 2015 10:53:46 -0400 Received: by qgem9 with SMTP id m9so63093799qge.1 for ; Fri, 30 Oct 2015 07:53:45 -0700 (PDT) In-Reply-To: <1446216811-2248-1-git-send-email-brood@attotech.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: linux-scsi@vger.kernel.org, xjtuwjp@gmail.com, James.Bottomley@HansenPartnership.com Cc: Benjamin Rood If MSI(X) interrupts are disabled via the kernel command line (pci=nomsi), the pm8001 driver will kernel panic because it does not detect that MSI interrupts are disabled and will soldier on and attempt to configure MSI interrupts anyways. This leads to a kernel panic, most likely because a required data structure is not available down the line. Using the pci_msi_enabled() function in order to detect if MSI interrupts are enabled before configuring them resolves this issue and avoids a kernel panic when the module is loaded. Additionally, the irq_vector structure must be initialized when legacy interrupts are being used otherwise legacy interrupts will simply not function and result in another panic. Signed-off-by: Benjamin Rood --- drivers/scsi/pm8001/pm8001_init.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/drivers/scsi/pm8001/pm8001_init.c b/drivers/scsi/pm8001/pm8001_init.c index ab99984..bdc624f 100644 --- a/drivers/scsi/pm8001/pm8001_init.c +++ b/drivers/scsi/pm8001/pm8001_init.c @@ -482,7 +482,8 @@ static struct pm8001_hba_info *pm8001_pci_alloc(struct pci_dev *pdev, #ifdef PM8001_USE_TASKLET /* Tasklet for non msi-x interrupt handler */ - if ((!pdev->msix_cap) || (pm8001_ha->chip_id == chip_8001)) + if ((!pdev->msix_cap || !pci_msi_enabled()) + || (pm8001_ha->chip_id == chip_8001)) tasklet_init(&pm8001_ha->tasklet[0], pm8001_tasklet, (unsigned long)&(pm8001_ha->irq_vector[0])); else @@ -951,7 +952,7 @@ static u32 pm8001_request_irq(struct pm8001_hba_info *pm8001_ha) pdev = pm8001_ha->pdev; #ifdef PM8001_USE_MSIX - if (pdev->msix_cap) + if (pdev->msix_cap && pci_msi_enabled()) return pm8001_setup_msix(pm8001_ha); else { PM8001_INIT_DBG(pm8001_ha, @@ -962,6 +963,8 @@ static u32 pm8001_request_irq(struct pm8001_hba_info *pm8001_ha) intx: /* initialize the INT-X interrupt */ + pm8001_ha->irq_vector[0].irq_id = 0; + pm8001_ha->irq_vector[0].drv_inst = pm8001_ha; rc = request_irq(pdev->irq, pm8001_interrupt_handler_intx, IRQF_SHARED, DRV_NAME, SHOST_TO_SAS_HA(pm8001_ha->shost)); return rc; @@ -1112,7 +1115,8 @@ static void pm8001_pci_remove(struct pci_dev *pdev) #endif #ifdef PM8001_USE_TASKLET /* For non-msix and msix interrupts */ - if ((!pdev->msix_cap) || (pm8001_ha->chip_id == chip_8001)) + if ((!pdev->msix_cap || !pci_msi_enabled()) || + (pm8001_ha->chip_id == chip_8001)) tasklet_kill(&pm8001_ha->tasklet[0]); else for (j = 0; j < PM8001_MAX_MSIX_VEC; j++) @@ -1161,7 +1165,8 @@ static int pm8001_pci_suspend(struct pci_dev *pdev, pm_message_t state) #endif #ifdef PM8001_USE_TASKLET /* For non-msix and msix interrupts */ - if ((!pdev->msix_cap) || (pm8001_ha->chip_id == chip_8001)) + if ((!pdev->msix_cap || !pci_msi_enabled()) || + (pm8001_ha->chip_id == chip_8001)) tasklet_kill(&pm8001_ha->tasklet[0]); else for (j = 0; j < PM8001_MAX_MSIX_VEC; j++) @@ -1231,7 +1236,8 @@ static int pm8001_pci_resume(struct pci_dev *pdev) goto err_out_disable; #ifdef PM8001_USE_TASKLET /* Tasklet for non msi-x interrupt handler */ - if ((!pdev->msix_cap) || (pm8001_ha->chip_id == chip_8001)) + if ((!pdev->msix_cap || !pci_msi_enabled()) || + (pm8001_ha->chip_id == chip_8001)) tasklet_init(&pm8001_ha->tasklet[0], pm8001_tasklet, (unsigned long)&(pm8001_ha->irq_vector[0])); else -- 2.4.3