Re: [PATCH] megaraid_sas: Don't issue kill adapter for MFI controllers in case of PD list DCMD failure

[Ewan Milne <emilne@redhat.com>]

On Thu, 2016-03-10 at 02:14 -0800, Sumit Saxena wrote:
> There are few MFI adapters which do not support MR_DCMD_PD_LIST_QUERY so
> if MFI adapters fail this DCMD, it should not be considered as FATAL and
> driver should not issue kill adapter and set per controller's instance
> variable- pd_list_not_supported so that same variable can be used inside
> functions- slave_alloc and slave_configure to allow firmware scan.
> 
> Killing adapter because of DCMD failure when this DCMD is not supported
> causes driver's probe getting failed. This issue got introduced because
> of below commit when MFI IO timeout handling was introduced-
> 
> 6d40afb megaraid_sas: MFI IO timeout handling
> 
> Killing adapter in case of this DCMD failure should be limited to Fusion
> adapters only. Per controller's instance variable allow_fw_scan is removed
> as pd_list_not_supported better reflect the purpose.
> 
> Signed-off-by: Sumit Saxena <sumit.saxena@broadcom.com>
> ---
>  drivers/scsi/megaraid/megaraid_sas.h      |  2 +-
>  drivers/scsi/megaraid/megaraid_sas_base.c | 14 ++++++++++----
>  2 files changed, 11 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/scsi/megaraid/megaraid_sas.h b/drivers/scsi/megaraid/megaraid_sas.h
> index 4484e63..fce414a 100644
> --- a/drivers/scsi/megaraid/megaraid_sas.h
> +++ b/drivers/scsi/megaraid/megaraid_sas.h
> @@ -2097,7 +2097,7 @@ struct megasas_instance {
>  	u8 UnevenSpanSupport;
>  
>  	u8 supportmax256vd;
> -	u8 allow_fw_scan;
> +	u8 pd_list_not_supported;
>  	u16 fw_supported_vd_count;
>  	u16 fw_supported_pd_count;
>  
> diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c
> index 5c08568..69d375b 100644
> --- a/drivers/scsi/megaraid/megaraid_sas_base.c
> +++ b/drivers/scsi/megaraid/megaraid_sas_base.c
> @@ -1838,7 +1838,7 @@ static int megasas_slave_configure(struct scsi_device *sdev)
>  	struct megasas_instance *instance;
>  
>  	instance = megasas_lookup_instance(sdev->host->host_no);
> -	if (instance->allow_fw_scan) {
> +	if (instance->pd_list_not_supported) {
>  		if (sdev->channel < MEGASAS_MAX_PD_CHANNELS &&
>  			sdev->type == TYPE_DISK) {
>  			pd_index = (sdev->channel * MEGASAS_MAX_DEV_PER_CHANNEL) +
> @@ -1874,7 +1874,8 @@ static int megasas_slave_alloc(struct scsi_device *sdev)
>  		pd_index =
>  			(sdev->channel * MEGASAS_MAX_DEV_PER_CHANNEL) +
>  			sdev->id;
> -		if ((instance->allow_fw_scan || instance->pd_list[pd_index].driveState ==
> +		if ((instance->pd_list_not_supported ||
> +			instance->pd_list[pd_index].driveState ==
>  			MR_PD_STATE_SYSTEM)) {
>  			goto scan_target;
>  		}
> @@ -4087,7 +4088,13 @@ megasas_get_pd_list(struct megasas_instance *instance)
>  
>  	switch (ret) {
>  	case DCMD_FAILED:
> -		megaraid_sas_kill_hba(instance);
> +		dev_info(&instance->pdev->dev, "MR_DCMD_PD_LIST_QUERY "
> +			"failed/not supported by firmware\n");
> +
> +		if (instance->ctrl_context)
> +			megaraid_sas_kill_hba(instance);
> +		else
> +			instance->pd_list_not_supported = 1;
>  		break;
>  	case DCMD_TIMEOUT:
>  
> @@ -5034,7 +5041,6 @@ static int megasas_init_fw(struct megasas_instance *instance)
>  	case PCI_DEVICE_ID_DELL_PERC5:
>  	default:
>  		instance->instancet = &megasas_instance_template_xscale;
> -		instance->allow_fw_scan = 1;
>  		break;
>  	}
>  

Note the comment "fixes 6d40afb megaraid_sas: MFI IO timeout handling"

Reviewed-by: Ewan D. Milne <emilne@redhat.com>