Am Mittwoch, 11. November 2009 21:49:59 schrieb Alan Stern:
> > I think it is necessary to do the rebinding in a second pass after
> > doing the notifications. But this is subtle. Alan, what do you think?
>
> You are right. But I would make the code a little cleaner...
Hi,
does this address the issues you had?
Regards
Oliver
--
commit 092d62009be992df7d6ba6c7c6acb91ca58567b5
Author: Oliver Neukum <oliver@xxxxxxxxxx>
Date: Wed Nov 25 10:22:20 2009 +0100
usb:fix unbalanced calls to post_reset() in usb_reset_device()
usb_reset_device() can mean drivers are disconnected or reconnected
for such drivers post_reset() must not be called. Therefore do the
post_reset() and the probing in two passes
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 5ce8391..b326ccc 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -3652,16 +3652,17 @@ int usb_reset_device(struct usb_device *udev)
int i;
struct usb_host_config *config = udev->actconfig;
- if (udev->state == USB_STATE_NOTATTACHED ||
- udev->state == USB_STATE_SUSPENDED) {
+ /* Prevent autosuspend during the reset */
+ ret = usb_autoresume_device(udev);
+ if (ret < 0)
+ return ret;
+
+ if (udev->state == USB_STATE_NOTATTACHED) {
dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
udev->state);
return -EINVAL;
}
- /* Prevent autosuspend during the reset */
- usb_autoresume_device(udev);
-
if (config) {
for (i = 0; i < config->desc.bNumInterfaces; ++i) {
struct usb_interface *cintf = config->interface[i];
@@ -3687,17 +3688,23 @@ int usb_reset_device(struct usb_device *udev)
for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
struct usb_interface *cintf = config->interface[i];
struct usb_driver *drv;
- int rebind = cintf->needs_binding;
- if (!rebind && cintf->dev.driver) {
+ if (!cintf->needs_binding && cintf->dev.driver) {
drv = to_usb_driver(cintf->dev.driver);
- if (drv->post_reset)
- rebind = (drv->post_reset)(cintf);
- else if (cintf->condition ==
- USB_INTERFACE_BOUND)
- rebind = 1;
+ cintf->needs_binding = (drv->post_reset)(cintf)
+ ? 1 : 0;
}
- if (ret == 0 && rebind)
+ }
+
+ /*
+ * Don't rebind until after all the post_reset() calls
+ * so that a newly bound driver does not get an unbalanced
+ * call to post_reset()
+ */
+ for (i = config->desc.bNumInterfaces - 1; i >= 0; --i){
+ struct usb_interface *cintf = config->interface[i];
+
+ if (ret == 0 && cintf->needs_binding)
usb_rebind_intf(cintf);
}
}
--
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