From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Brownell <david-b@pacbell.net>
Subject: Re: Usb storage mounting was broken
Date: Wed, 22 Oct 2003 15:53:05 -0700
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To: Nicolas Mailhot <Nicolas.Mailhot@laPoste.net>
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>>And since this resembles an enumeration failure, it'd be good
>>to have the Alt-Sysrq-t output for "khubd".
> 
> In the report too (took me some time to remember it ended up in
> /var/log/messages, not only the current console)

That says to me "self-deadlock"; crept in recently.  It turns
out that routine already has all the locks it needs.  Try the
attached patch.

This is pretty far from being a mount problem ... no wonder I
kept expecting more info from you!

- Dave

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--- 1.37/drivers/usb/core/message.c	Tue Sep 23 11:18:09 2003
+++ edited/drivers/usb/core/message.c	Wed Oct 22 15:49:15 2003
@@ -1001,8 +1001,10 @@
 	int			i, retval;
 	struct usb_host_config	*config;
 
-	/* dev->serialize guards all config changes */
-	down(&dev->serialize);
+	/* caller must own dev->serialize (config won't change)
+	 * and the usb bus readlock (so driver bindings are stable);
+	 * so calls during probe() are fine
+	 */
 
 	for (i = 1; i < 16; ++i) {
 		usb_disable_endpoint(dev, i);
@@ -1016,7 +1018,7 @@
 			NULL, 0, HZ * USB_CTRL_SET_TIMEOUT);
 	if (retval < 0) {
 		dev->state = USB_STATE_ADDRESS;
-		goto done;
+		return retval;
 	}
 
 	dev->toggle[0] = dev->toggle[1] = 0;
@@ -1029,9 +1031,7 @@
 		intf->act_altsetting = 0;
 		usb_enable_interface(dev, intf);
 	}
-done:
-	up(&dev->serialize);
-	return (retval < 0) ? retval : 0;
+	return 0;
 }
 
 /**

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