Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752608Ab0DLQRY (ORCPT ); Mon, 12 Apr 2010 12:17:24 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:46053 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752175Ab0DLQRW (ORCPT ); Mon, 12 Apr 2010 12:17:22 -0400 Date: Mon, 12 Apr 2010 12:17:22 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Andi Kleen cc: Daniel Mack , Pedro Ribeiro , , , Greg KH , , Subject: Re: USB transfer_buffer allocations on 64bit systems In-Reply-To: <20100412154323.GP18855@one.firstfloor.org> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1054 Lines: 26 On Mon, 12 Apr 2010, Andi Kleen wrote: > > Well, the sound driver itself doesn't care for any of those things, just > > like any other USB driver doesn't. The USB core itself of the host > > controller driver should do, and as far as I can see, it does that, yes. > > Hmm, still things must go wrong somewhere. Perhaps need some instrumentation > to see if all the transfer buffers really hit the PCI mapping functions. Such a test has already been carried out earlier in this thread: http://marc.info/?l=linux-usb&m=127074587029353&w=2 http://marc.info/?l=linux-usb&m=127076841801051&w=2 http://marc.info/?l=linux-usb&m=127082890510415&w=2 > It might be interesting to test if the device works with enabled > IOMMU. That would trigger any failures to properly map the buffers > earlier. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/