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From: Oliver Neukum <oliver@neukum.org>
To: Jeff Chua <jeff.chua.linux@gmail.com>
Subject: Re: commit 554f76962d3a6eb5110415f1591aca83f96a84ae hangs USB for vmware 7.0.1
Date: Sat, 6 Mar 2010 10:03:50 +0100
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Cc: Linus Torvalds <torvalds@linux-foundation.org>,
       Jeff Chua <jeff.tw.chua@gmail.com>,
       Linux Kernel <linux-kernel@vger.kernel.org>,
       "Greg Kroah-Hartman" <gregkh@suse.de>,
       Frederic Weisbecker <fweisbec@gmail.com>, petr@vmware.com,
       Eli Collins <ecollins@vmware.com>
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Am Samstag, 6. März 2010 06:22:48 schrieb Jeff Chua:
> It seems to hang trying to read from /proc/bus/usb/devices.
> 
> So, next I just try to "cat /proc/bus/usb/devices" and it hangs as well.
> 
> Reverting the commit makes "cat /proc/bus/usb/devices" works again.
> 
> Does this happen to me only?

As far as I can tell, yes. I cannot replicate it.

Please get me at least a sysrq-T trace.
There's no obvious place usb_device_read() takes usbfs_mutex.

	Regards
		Oliver