It happens when enable debug log, if set_alt() returns USB_GADGET_DELAYED_STATUS and usb_composite_setup_continue() is called before increasing count of @delayed_status, so fix it by using spinlock of @cdev->lock. Signed-off-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx> Tested-by: Jay Hsu <shih-chieh.hsu@xxxxxxxxxxxx> --- drivers/usb/gadget/composite.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c index f242c2b..d2fa071 100644 --- a/drivers/usb/gadget/composite.c +++ b/drivers/usb/gadget/composite.c @@ -1719,6 +1719,8 @@ static int fill_ext_prop(struct usb_configuration *c, int interface, u8 *buf) */ if (w_value && !f->get_alt) break; + + spin_lock(&cdev->lock); value = f->set_alt(f, w_index, w_value); if (value == USB_GADGET_DELAYED_STATUS) { DBG(cdev, @@ -1728,6 +1730,7 @@ static int fill_ext_prop(struct usb_configuration *c, int interface, u8 *buf) DBG(cdev, "delayed_status count %d\n", cdev->delayed_status); } + spin_unlock(&cdev->lock); break; case USB_REQ_GET_INTERFACE: if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE)) -- 1.9.1 -- 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