Return-path: Received: from mail-vx0-f174.google.com ([209.85.220.174]:56598 "EHLO mail-vx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752386Ab1HYR3x (ORCPT ); Thu, 25 Aug 2011 13:29:53 -0400 Received: by vxi9 with SMTP id 9so1878262vxi.19 for ; Thu, 25 Aug 2011 10:29:53 -0700 (PDT) Message-ID: <4E56868E.7010404@lwfinger.net> (sfid-20110825_192956_840703_81788327) Date: Thu, 25 Aug 2011 12:29:50 -0500 From: Larry Finger MIME-Version: 1.0 To: =?UTF-8?B?UmFmYcWCIE1pxYJlY2tp?= CC: John W Linville , Michael Buesch , b43-dev@lists.infradead.org, linux-wireless@vger.kernel.org Subject: Re: [RFC/RFT] b43: Relax requirement for descriptors to be in the DMA zone References: <4e55750c.GPPIrbNLynUMWY/U%Larry.Finger@lwfinger.net> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 08/25/2011 12:24 PM, Rafał Miłecki wrote: > 2011/8/25 Larry Finger: >> When 64-bit DMA was first used, there were problems with the >> BCM4311 (14e4:4311). The problem was "fixed" by using the GFP_DMA >> flag in the allocation of coherent ring descriptor memory. >> >> The original problem is now believed to have been due to bugs in >> the 64-bit DMA implementation in the rest of the kernel, and that >> those bugs have been fixed. Accordingly, the requirement for the >> descriptors to be in the DMA zone is relaxed. > > Larry, it is not clear to me from the commit message: did you test > that patch with your 14e4:4311? Yes. Larry