On Tue, 2017-11-07 at 12:59 -0800, James Smart wrote:
> From: Dick Kennedy <dick.kennedy@xxxxxxxxxxxx>
>
> System crashed due to a hard lockup at lpfc_els_timeout_handler+0x128.
>
> The els ring's txcmplq list is corrupted: the last element in the list
> does not point back the the head causing a loop. Issue is the
> els processing path for sli4 hbas are using the hbalock instead of
> the ring_lock for removing elements from the txcmplq list.
>
> Use the adapter SLI_REV to determine which lock should be used for
> removing iocbqs from the els rings txcmplq.
>
> note: the future refactoring will address this so that we don't have
> this ugly type-based lock code.
>
> Signed-off-by: Dick Kennedy <dick.kennedy@xxxxxxxxxxxx>
> Signed-off-by: James Smart <james.smart@xxxxxxxxxxxx>
> ---
> drivers/scsi/lpfc/lpfc_sli.c | 13 ++++++++++---
> 1 file changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
> index 1229f58bdd09..c1c7df607604 100644
> --- a/drivers/scsi/lpfc/lpfc_sli.c
> +++ b/drivers/scsi/lpfc/lpfc_sli.c
> @@ -2732,7 +2732,8 @@ lpfc_sli_process_unsol_iocb(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
> *
> * This function looks up the iocb_lookup table to get the command iocb
> * corresponding to the given response iocb using the iotag of the
> - * response iocb. This function is called with the hbalock held.
> + * response iocb. This function is called with the hbalock held
> + * for sli3 devices or the ring_lock for sli4 devices.
> * This function returns the command iocb object if it finds the command
> * iocb else returns NULL.
> **/
> @@ -2828,9 +2829,15 @@ lpfc_sli_process_sol_iocb(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
> unsigned long iflag;
>
> /* Based on the iotag field, get the cmd IOCB from the txcmplq */
> - spin_lock_irqsave(&phba->hbalock, iflag);
> + if (phba->sli_rev == LPFC_SLI_REV4)
> + spin_lock_irqsave(&pring->ring_lock, iflag);
> + else
> + spin_lock_irqsave(&phba->hbalock, iflag);
> cmdiocbp = lpfc_sli_iocbq_lookup(phba, pring, saveq);
> - spin_unlock_irqrestore(&phba->hbalock, iflag);
> + if (phba->sli_rev == LPFC_SLI_REV4)
> + spin_unlock_irqrestore(&pring->ring_lock, iflag);
> + else
> + spin_unlock_irqrestore(&phba->hbalock, iflag);
>
> if (cmdiocbp) {
> if (cmdiocbp->iocb_cmpl) {
The other callers of lpfc_sli_iocbq_lookup() use the 2 different locks,
depending upon the SLI-3/SLI-4 case.
Reviewed-by: Ewan D. Milne <emilne@xxxxxxxxxx>
