isci: validate oem parameters early, and fallback

If the platform specifies invalid parameters warn the user and fallback to
internal defaults rather than fail the driver load altogether.

Reported-by: Yinghai Lu <yinghai.lu@oracle.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

3 files changed, 49 insertions, 38 deletions

diff --git a/drivers/scsi/isci/core/scic_config_parameters.h b/drivers/scsi/isci/core/scic_config_parameters.h
index cb6abcc7e7cd..716abfcd0c23 100644
--- a/drivers/scsi/isci/core/scic_config_parameters.h
+++ b/drivers/scsi/isci/core/scic_config_parameters.h
@@ -279,6 +279,8 @@ enum sci_status scic_oem_parameters_set(
         struct scic_sds_controller *controller,
         union scic_oem_parameters *oem_parameters);
 
+int scic_oem_parameters_validate(struct scic_sds_oem_params *oem);
+
 /**
  * scic_oem_parameters_get() - This method allows the user to retreive the OEM
  *    parameters utilized by the controller.
diff --git a/drivers/scsi/isci/core/scic_sds_controller.c b/drivers/scsi/isci/core/scic_sds_controller.c
index 8194618b76c6..9bb78a2e6ff7 100644
--- a/drivers/scsi/isci/core/scic_sds_controller.c
+++ b/drivers/scsi/isci/core/scic_sds_controller.c
@@ -2455,52 +2455,51 @@ enum sci_status scic_user_parameters_set(
         return SCI_FAILURE_INVALID_STATE;
 }
 
-enum sci_status scic_oem_parameters_set(
-        struct scic_sds_controller *scic,
-        union scic_oem_parameters *scic_parms)
+int scic_oem_parameters_validate(struct scic_sds_oem_params *oem)
 {
-        u32 state = scic->state_machine.current_state_id;
+        int i;
 
-        if (state == SCI_BASE_CONTROLLER_STATE_RESET ||
-            state == SCI_BASE_CONTROLLER_STATE_INITIALIZING ||
-            state == SCI_BASE_CONTROLLER_STATE_INITIALIZED) {
-                u16 index;
-                u8  combined_phy_mask = 0;
+        for (i = 0; i < SCI_MAX_PORTS; i++)
+                if (oem->ports[i].phy_mask > SCIC_SDS_PARM_PHY_MASK_MAX)
+                        return -EINVAL;
+
+        for (i = 0; i < SCI_MAX_PHYS; i++)
+                if (oem->phys[i].sas_address.high == 0 &&
+                    oem->phys[i].sas_address.low == 0)
+                        return -EINVAL;
+
+        if (oem->controller.mode_type == SCIC_PORT_AUTOMATIC_CONFIGURATION_MODE) {
+                for (i = 0; i < SCI_MAX_PHYS; i++)
+                        if (oem->ports[i].phy_mask != 0)
+                                return -EINVAL;
+        } else if (oem->controller.mode_type == SCIC_PORT_MANUAL_CONFIGURATION_MODE) {
+                u8 phy_mask = 0;
+
+                for (i = 0; i < SCI_MAX_PHYS; i++)
+                        phy_mask |= oem->ports[i].phy_mask;
+
+                if (phy_mask == 0)
+                        return -EINVAL;
+        } else
+                return -EINVAL;
 
-                /*
-                 * Validate the oem parameters.  If they are not legal, then
-                 * return a failure. */
-                for (index = 0; index < SCI_MAX_PORTS; index++) {
-                        if (scic_parms->sds1.ports[index].phy_mask > SCIC_SDS_PARM_PHY_MASK_MAX)
-                                return SCI_FAILURE_INVALID_PARAMETER_VALUE;
-                }
+        if (oem->controller.max_concurrent_dev_spin_up > MAX_CONCURRENT_DEVICE_SPIN_UP_COUNT)
+                return -EINVAL;
 
-                for (index = 0; index < SCI_MAX_PHYS; index++) {
-                        if ((scic_parms->sds1.phys[index].sas_address.high == 0) &&
-                            (scic_parms->sds1.phys[index].sas_address.low == 0))
-                                return SCI_FAILURE_INVALID_PARAMETER_VALUE;
-                }
+        return 0;
+}
 
-                if (scic_parms->sds1.controller.mode_type ==
-                                SCIC_PORT_AUTOMATIC_CONFIGURATION_MODE) {
-                        for (index = 0; index < SCI_MAX_PHYS; index++) {
-                                if (scic_parms->sds1.ports[index].phy_mask != 0)
-                                        return SCI_FAILURE_INVALID_PARAMETER_VALUE;
-                        }
-                } else if (scic_parms->sds1.controller.mode_type ==
-                                SCIC_PORT_MANUAL_CONFIGURATION_MODE) {
-                        for (index = 0; index < SCI_MAX_PHYS; index++)
-                                combined_phy_mask |= scic_parms->sds1.ports[index].phy_mask;
+enum sci_status scic_oem_parameters_set(struct scic_sds_controller *scic,
+                                        union scic_oem_parameters *scic_parms)
+{
+        u32 state = scic->state_machine.current_state_id;
 
-                        if (combined_phy_mask == 0)
-                                return SCI_FAILURE_INVALID_PARAMETER_VALUE;
-                } else
-                        return SCI_FAILURE_INVALID_PARAMETER_VALUE;
+        if (state == SCI_BASE_CONTROLLER_STATE_RESET ||
+            state == SCI_BASE_CONTROLLER_STATE_INITIALIZING ||
+            state == SCI_BASE_CONTROLLER_STATE_INITIALIZED) {
 
-                if (scic_parms->sds1.controller.max_concurrent_dev_spin_up >
-                                MAX_CONCURRENT_DEVICE_SPIN_UP_COUNT)
+                if (scic_oem_parameters_validate(&scic_parms->sds1))
                         return SCI_FAILURE_INVALID_PARAMETER_VALUE;
-
                 scic->oem_parameters.sds1 = scic_parms->sds1;
 
                 return SCI_SUCCESS;
diff --git a/drivers/scsi/isci/init.c b/drivers/scsi/isci/init.c
index 5da9a6925cd7..015ce94453bb 100644
--- a/drivers/scsi/isci/init.c
+++ b/drivers/scsi/isci/init.c
@@ -489,6 +489,16 @@ static int __devinit isci_pci_probe(struct pci_dev *pdev, const struct pci_devic
         else
                 orom = isci_request_oprom(pdev);
 
+        for (i = 0; orom && i < ARRAY_SIZE(orom->ctrl); i++) {
+                if (scic_oem_parameters_validate(&orom->ctrl[i])) {
+                        dev_warn(&pdev->dev,
+                                 "[%d]: invalid oem parameters detected, falling back to firmware\n", i);
+                        devm_kfree(&pdev->dev, orom);
+                        orom = NULL;
+                        break;
+                }
+        }
+
         if (!orom) {
                 source = "(firmware)";
                 orom = isci_request_firmware(pdev, fw);