CHROMIUM: TEMPORARY: dump stack to help debug p/17609

This doesn't happen very often, so the dump_stack should
be tolerable.  I tried with a WARN_ON, but it made some
of our automated tests fail.

BUG=chrome-os-partner:17609
TEST=none

Change-Id: I3d5a0ebc25d272901e713209dc5d655322804f91
Signed-off-by: Luigi Semenzato <semenzato@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/44178
Reviewed-by: Sonny Rao <sonnyrao@chromium.org>

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 572769b..81b2dbe 100644 (file)
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -3019,11 +3019,17 @@ hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
        else
                speed = usb_speed_string(udev->speed);
 
-       if (udev->speed != USB_SPEED_SUPER)
+       if (udev->speed != USB_SPEED_SUPER) {
                dev_info(&udev->dev,
                                "%s %s USB device number %d using %s\n",
                                (udev->config) ? "reset" : "new", speed,
                                devnum, udev->bus->controller->driver->name);
+               if (udev->config) {
+                       /* for crosbug.com/p/17609 */
+                       dev_info(&udev->dev, "DEBUG: USB RESET\n");
+                       dump_stack();
+               }
+       }
 
        /* Set up TT records, if needed  */
        if (hdev->tt) {