On Tue, Jul 05, 2011 at 12:37:26PM +0530, Amit Nagal wrote: > so do the usb-core layers or VFS layers maintains some locks that take > care that if read / write is in progress > and application calls close() , corresponding release() method in usb > driver will be called only upon completion > of all read / writes ? No, release will be called when all of the userspace file handles call close(), and not before. hope this helps, greg k-h -- 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