From 79abe2bd501d628b165f323098d6972d69bd13d7 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Wed, 16 Mar 2016 13:20:51 +0100 Subject: [PATCH] uas: Limit qdepth at the scsi-host level Commit 64d513ac31bd ("scsi: use host wide tags by default") causes the scsi-core to queue more cmnds then we can handle on devices with multiple LUNs, limit the qdepth at the scsi-host level instead of per slave to fix this. BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1315013 Cc: stable@vger.kernel.org # 4.4.x and 4.5.x Signed-off-by: Hans de Goede --- drivers/usb/storage/uas.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c index c90a7e4..b5cb7ab 100644 --- a/drivers/usb/storage/uas.c +++ b/drivers/usb/storage/uas.c @@ -800,7 +800,6 @@ static int uas_slave_configure(struct scsi_device *sdev) if (devinfo->flags & US_FL_BROKEN_FUA) sdev->broken_fua = 1; - scsi_change_queue_depth(sdev, devinfo->qdepth - 2); return 0; } @@ -932,6 +931,12 @@ static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id) if (result) goto set_alt0; + /* + * 1 tag is reserved for untagged commands + + * 1 tag to avoid of by one errors in some bridge firmwares + */ + shost->can_queue = devinfo->qdepth - 2; + usb_set_intfdata(intf, shost); result = scsi_add_host(shost, &intf->dev); if (result) -- 2.7.3