RE: [PATCH] scsi: storvsc: Cap scsi_driver.can_queue to fix a hang issue during boot

[Dexuan Cui]

> From: John Garry <john.garry@xxxxxxxxxx>
> Sent: Wednesday, October 6, 2021 9:03 AM
> >> ...
> >>> +	if (scsi_driver.can_queue > SHRT_MAX)
> >>> +		scsi_driver.can_queue = SHRT_MAX;
> >>> +
> >
> > This fix works, but is a more of a temporary hack until I can finish
> > a larger overhaul of the algorithm.
> 
> > But for now, I think the better
> > fix is for ea2f0f77538c to do the comparison as "int" instead of "short".
> >
> 
> That seems better to me. But Let's wait for other possible opinion.
> 
> Thanks,
> John

It looks like shost->cmd_per_lun has been "short" since day 1.
I don't know whether it should be changed to unsigned int.

Thanks for the thoughts! I'll post a v2 like the below in 24 hours.

diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c
index 3f6f14f0cafb..24b72ee4246f 100644
--- a/drivers/scsi/hosts.c
+++ b/drivers/scsi/hosts.c
@@ -220,7 +220,8 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev,
                goto fail;
        }

-       shost->cmd_per_lun = min_t(short, shost->cmd_per_lun,
+       /* Use min_t(int, ...) in case shost->can_queue exceeds SHRT_MAX */
+       shost->cmd_per_lun = min_t(int, shost->cmd_per_lun,
                                   shost->can_queue);

        error = scsi_init_sense_cache(shost)