Function sdev_store_queue_depth() enforces that the sdev queue depth cannot exceed shost.can_queue.
However, the LLDD may still set cmd_per_lun > can_queue, which leads to an initial sdev queue depth greater than can_queue. Stop this happened by capping initial sdev queue depth at can_queue. Signed-off-by: John Garry <john.ga...@huawei.com> --- Topic originally discussed at: https://lore.kernel.org/linux-scsi/85dec8eb-8eab-c7d6-b0fb-5622747c5...@interlog.com/T/#m5663d0cac657d843b93d0c9a2374f98fc04384b9 Last idea there was to error/warn in scsi_add_host() for cmd_per_lun > can_queue. However, such a shost driver could still configure the sdev queue depth to be sound value at .slave_configure callback, so now thinking the orig patch better. diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index 9f1b7f3c650a..8de2f830bcdc 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -277,7 +277,11 @@ static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget, WARN_ON_ONCE(!blk_get_queue(sdev->request_queue)); sdev->request_queue->queuedata = sdev; - depth = sdev->host->cmd_per_lun ?: 1; + if (sdev->host->cmd_per_lun) + depth = min_t(unsigned int, sdev->host->cmd_per_lun, + sdev->host->can_queue); + else + depth = 1; /* * Use .can_queue as budget map's depth because we have to -- 2.26.2
