On Mon, 2015-04-27 at 09:02 +0200, Hannes Reinecke wrote: > On 04/26/2015 08:52 PM, James Bottomley wrote: > > On Sun, 2015-04-26 at 16:57 +0200, Ondrej Zary wrote: > >> On Friday 24 April 2015 13:18:38 Hannes Reinecke wrote: > >>> Ancient, and pretty much obsolete by now. > >>> > >>> Signed-off-by: Hannes Reinecke <hare@xxxxxxx> > >>> --- > >>> drivers/scsi/advansys.c | 18 ------------------ > >>> 1 file changed, 18 deletions(-) > >>> > >>> diff --git a/drivers/scsi/advansys.c b/drivers/scsi/advansys.c > >>> index 74e5518..5a55272 100644 > >>> --- a/drivers/scsi/advansys.c > >>> +++ b/drivers/scsi/advansys.c > >>> @@ -11212,24 +11212,6 @@ static int advansys_board_found(struct Scsi_Host > >>> *shost, unsigned int iop, } > >>> > >>> /* > >>> - * Following v1.3.89, 'cmd_per_lun' is no longer needed > >>> - * and should be set to zero. > >>> - * > >>> - * But because of a bug introduced in v1.3.89 if the driver is > >>> - * compiled as a module and 'cmd_per_lun' is zero, the Mid-Level > >>> - * SCSI function 'allocate_device' will panic. To allow the driver > >>> - * to work as a module in these kernels set 'cmd_per_lun' to 1. > >>> - * > >>> - * Note: This is wrong. cmd_per_lun should be set to the depth > >>> - * you want on untagged devices always. > >>> - #ifdef MODULE > >>> - */ > >>> - shost->cmd_per_lun = 1; > >>> -/* #else > >>> - shost->cmd_per_lun = 0; > >>> -#endif */ > >>> - > >>> - /* > >>> * Set the maximum number of scatter-gather elements the > >>> * adapter can handle. > >>> */ > >> > >> This patch breaks my setup: "modprobe advansys" hangs. > >> > >> It works when all other patches are applied except this one. > > > > The specific problem is that a cmd_per_lun of zero breaks everything > > because we use it for the initial queue depth and if you don't actually > > set it, you get zero (because the template is in static memory). This > > should be a global fix that changes the default initial queue depth to 1 > > for the probe phase if it's unset in the template or the host. > > > > Hopefully this should set us up for removing cmd_per_lun. > > > > James > > > > --- > > > > diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c > > index 60aae01..681a59a 100644 > > --- a/drivers/scsi/scsi_scan.c > > +++ b/drivers/scsi/scsi_scan.c > > @@ -280,7 +280,8 @@ static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget, > > sdev->host->cmd_per_lun, shost->bqt, > > shost->hostt->tag_alloc_policy); > > } > > - scsi_change_queue_depth(sdev, sdev->host->cmd_per_lun); > > + scsi_change_queue_depth(sdev, sdev->host->cmd_per_lun ? > > + sdev->host->cmd_per_lun : 1); > > > > scsi_sysfs_device_initialize(sdev); > > > > > > > > > That fixes it on my side; tested with two devices on the narrow > board and one on the wide board. > > And while at it I've done a patch to clear up all the now-obsolete > cmd_per_lun = 1 settings in the various drivers. > > James, will you send a formal patch or should I send it, along with > the second one to clear up cmd_per_lun? I suppose I should do it formally first. After that, it might make sense for you to send it to me so I don't get the order wrong. James -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
