From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> This patch has been added to the 4.1 stable tree. If you have any objections, please let us know. =============== [ Upstream commit 19454462acb1bdef80542061bdc9b410e4ed1ff6 ] In current acm driver, the bulk-in callback function ignores the URBs unlinked in usb core. This causes unexpected data loss in some cases. For example, runtime suspend entry will unlinked all urbs and set urb->status to -ENOENT even those urbs might have data not processed yet. Hence, data loss occurs. This patch lets bulk-in callback function handle unlinked urbs to avoid data loss. Signed-off-by: Tang Jian Qiang <jianqiang.tang@xxxxxxxxx> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Acked-by: Oliver Neukum <oneukum@xxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx> --- drivers/usb/class/cdc-acm.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index 0fe15ae..2bf51b2 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -432,7 +432,8 @@ static void acm_read_bulk_callback(struct urb *urb) set_bit(rb->index, &acm->read_urbs_free); dev_dbg(&acm->data->dev, "%s - non-zero urb status: %d\n", __func__, status); - return; + if ((status != -ENOENT) || (urb->actual_length == 0)) + return; } usb_mark_last_busy(acm->dev); -- 2.5.0 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html