[SCSI] megaraid_sas: Add driver workaround for PERC5/1068 kdump kernel panic

The following patch for megaraid_sas adds a driver workaround for
PERC5/1068 based controller FW that keeps a command from the main
kernel that the driver cannot cancel which was causing a kernel panic
in shutdown of the kdump kernel.

Signed-off-by: Adam Radford <aradford@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

2 files changed, 19 insertions, 1 deletions

diff --git a/drivers/scsi/megaraid/megaraid_sas.h b/drivers/scsi/megaraid/megaraid_sas.h
index 9ffb92daa58b..7375fde2ab4f 100644
--- a/drivers/scsi/megaraid/megaraid_sas.h
+++ b/drivers/scsi/megaraid/megaraid_sas.h
@@ -139,6 +139,7 @@
 #define MFI_CMD_ABORT                           0x06
 #define MFI_CMD_SMP                             0x07
 #define MFI_CMD_STP                             0x08
+#define MFI_CMD_INVALID                         0xff
 
 #define MR_DCMD_CTRL_GET_INFO                   0x01010000
 #define MR_DCMD_LD_GET_LIST                     0x03010000
diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c
index ec09d5c2ed90..de2f47c439c7 100644
--- a/drivers/scsi/megaraid/megaraid_sas_base.c
+++ b/drivers/scsi/megaraid/megaraid_sas_base.c
@@ -215,6 +215,10 @@ megasas_return_cmd(struct megasas_instance *instance, struct megasas_cmd *cmd)
 
         cmd->scmd = NULL;
         cmd->frame_count = 0;
+        if ((instance->pdev->device != PCI_DEVICE_ID_LSI_FUSION) &&
+            (instance->pdev->device != PCI_DEVICE_ID_LSI_INVADER) &&
+            (reset_devices))
+                cmd->frame->hdr.cmd = MFI_CMD_INVALID;
         list_add_tail(&cmd->list, &instance->cmd_pool);
 
         spin_unlock_irqrestore(&instance->cmd_pool_lock, flags);
@@ -2165,7 +2169,16 @@ megasas_complete_cmd(struct megasas_instance *instance, struct megasas_cmd *cmd,
                 cmd->scmd->SCp.ptr = NULL;
 
         switch (hdr->cmd) {
-
+        case MFI_CMD_INVALID:
+                /* Some older 1068 controller FW may keep a pended
+                   MR_DCMD_CTRL_EVENT_GET_INFO left over from the main kernel
+                   when booting the kdump kernel.  Ignore this command to
+                   prevent a kernel panic on shutdown of the kdump kernel. */
+                printk(KERN_WARNING "megaraid_sas: MFI_CMD_INVALID command "
+                       "completed.\n");
+                printk(KERN_WARNING "megaraid_sas: If you have a controller "
+                       "other than PERC5, please upgrade your firmware.\n");
+                break;
         case MFI_CMD_PD_SCSI_IO:
         case MFI_CMD_LD_SCSI_IO:
 
@@ -2934,6 +2947,10 @@ static int megasas_create_frame_pool(struct megasas_instance *instance)
                 memset(cmd->frame, 0, total_sz);
                 cmd->frame->io.context = cmd->index;
                 cmd->frame->io.pad_0 = 0;
+                if ((instance->pdev->device != PCI_DEVICE_ID_LSI_FUSION) &&
+                    (instance->pdev->device != PCI_DEVICE_ID_LSI_INVADER) &&
+                    (reset_devices))
+                        cmd->frame->hdr.cmd = MFI_CMD_INVALID;
         }
 
         return 0;