[PATCH v2 02/15] lpfc: Fix system crash when port is reset.

[Guilherme G. Piccoli]

On 05/15/2017 07:20 PM, James Smart wrote:
> The driver panic when using the els_wq during port reset.
> 
> Check for NULL els_wq before dereferencing.

James/Dick, if possible please take a look on:
https://marc.info/?l=linux-scsi&m=149487670315697

For some reason that email didn't get threaded as I expect. And also I
forgot to include James' Gmail address, sorry.

Thanks in advance,


Guilherme

> 
> Signed-off-by: Dick Kennedy <dick.kennedy at broadcom.com>
> Signed-off-by: James Smart <james.smart at broadcom.com>
> Reviewed-by: Hannes Reinecke <hare at suse.com>
> ---
>  drivers/scsi/lpfc/lpfc.h         | 8 ++++++--
>  drivers/scsi/lpfc/lpfc_hbadisc.c | 6 +++---
>  2 files changed, 9 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/scsi/lpfc/lpfc.h b/drivers/scsi/lpfc/lpfc.h
> index 6d7840b096e6..62571fa9c6ad 100644
> --- a/drivers/scsi/lpfc/lpfc.h
> +++ b/drivers/scsi/lpfc/lpfc.h
> @@ -1228,7 +1228,11 @@ lpfc_sli_read_hs(struct lpfc_hba *phba)
>  static inline struct lpfc_sli_ring *
>  lpfc_phba_elsring(struct lpfc_hba *phba)
>  {
> -	if (phba->sli_rev == LPFC_SLI_REV4)
> -		return phba->sli4_hba.els_wq->pring;
> +	if (phba->sli_rev == LPFC_SLI_REV4) {
> +		if (phba->sli4_hba.els_wq)
> +			return phba->sli4_hba.els_wq->pring;
> +		else
> +			return NULL;
> +	}
>  	return &phba->sli.sli3_ring[LPFC_ELS_RING];
>  }
> diff --git a/drivers/scsi/lpfc/lpfc_hbadisc.c b/drivers/scsi/lpfc/lpfc_hbadisc.c
> index 0482c5580331..dcc9b3858778 100644
> --- a/drivers/scsi/lpfc/lpfc_hbadisc.c
> +++ b/drivers/scsi/lpfc/lpfc_hbadisc.c
> @@ -693,9 +693,9 @@ lpfc_work_done(struct lpfc_hba *phba)
>  	pring = lpfc_phba_elsring(phba);
>  	status = (ha_copy & (HA_RXMASK  << (4*LPFC_ELS_RING)));
>  	status >>= (4*LPFC_ELS_RING);
> -	if ((status & HA_RXMASK) ||
> -	    (pring->flag & LPFC_DEFERRED_RING_EVENT) ||
> -	    (phba->hba_flag & HBA_SP_QUEUE_EVT)) {
> +	if (pring && (status & HA_RXMASK ||
> +		      pring->flag & LPFC_DEFERRED_RING_EVENT ||
> +		      phba->hba_flag & HBA_SP_QUEUE_EVT)) {
>  		if (pring->flag & LPFC_STOP_IOCB_EVENT) {
>  			pring->flag |= LPFC_DEFERRED_RING_EVENT;
>  			/* Set the lpfc data pending flag */
>