On Fri, Feb 17, 2017 at 09:23:10AM +0100, Hannes Reinecke wrote: > The mpt3sas driver requires a reserved command space to handle > SCSI passthrough commands. > > Signed-off-by: Hannes Reinecke <[email protected]> > --- > drivers/scsi/mpt3sas/mpt3sas_base.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c > b/drivers/scsi/mpt3sas/mpt3sas_base.c > index e9470a3..97189ad 100644 > --- a/drivers/scsi/mpt3sas/mpt3sas_base.c > +++ b/drivers/scsi/mpt3sas/mpt3sas_base.c > @@ -2360,6 +2360,8 @@ struct scsiio_tracker * > } else { > u32 unique_tag = blk_mq_unique_tag(scmd->request); > u16 tag = blk_mq_unique_tag_to_tag(unique_tag); > + > + WARN_ON(tag < ioc->shost->reserved_cmds); > request = scsi_cmd_priv(scmd); > smid = tag + 1; > } > @@ -3521,7 +3523,8 @@ void mpt3sas_base_clear_st(struct MPT3SAS_ADAPTER *ioc, > /* set the scsi host can_queue depth > * with some internal commands that could be outstanding > */ > - ioc->shost->can_queue = ioc->scsiio_depth - INTERNAL_SCSIIO_CMDS_COUNT; > + ioc->shost->reserved_cmds = INTERNAL_SCSIIO_CMDS_COUNT; > + ioc->shost->can_queue = ioc->scsiio_depth - ioc->shost->reserved_cmds;
You're never allocating a reserved request. Just remove the number of reserved cmds from can_queue and you can use them on your own. So I don't think you'll actually need to use reserved request here, but instead you should set up can_queue properly earlier in the series.
