The ALWAYS_SYNC flag is currently honored by the usb-storage driver but not UAS and is required to work around devices that become unstable upon being queried for cache. This code is taken straight from: drivers/usb/storage/scsiglue.c:284 Signed-off-by: Alexander Kappner <agk@xxxxxxxxxxx> --- drivers/usb/storage/uas.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c index 6034c39..9e9de54 100644 --- a/drivers/usb/storage/uas.c +++ b/drivers/usb/storage/uas.c @@ -836,6 +836,12 @@ static int uas_slave_configure(struct scsi_device *sdev) if (devinfo->flags & US_FL_BROKEN_FUA) sdev->broken_fua = 1; + /* UAS also needs to support FL_ALWAYS_SYNC */ + if (devinfo->flags & US_FL_ALWAYS_SYNC) { + sdev->skip_ms_page_3f = 1; + sdev->skip_ms_page_8 = 1; + sdev->wce_default_on = 1; + } scsi_change_queue_depth(sdev, devinfo->qdepth - 2); return 0; } -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html