Return-path: Received: from mail-ew0-f46.google.com ([209.85.215.46]:40221 "EHLO mail-ew0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751833Ab1HXQx4 (ORCPT ); Wed, 24 Aug 2011 12:53:56 -0400 Received: by ewy4 with SMTP id 4so574590ewy.19 for ; Wed, 24 Aug 2011 09:53:55 -0700 (PDT) Message-ID: <4E552C9F.1020104@lwfinger.net> (sfid-20110824_185400_444098_DB32F68D) Date: Wed, 24 Aug 2011 11:53:51 -0500 From: Larry Finger MIME-Version: 1.0 To: =?UTF-8?B?TWljaGFlbCBCw7xzY2g=?= CC: =?UTF-8?B?UmFmYcWCIE1pxYJlY2tp?= , linux-wireless@vger.kernel.org, b43-dev@lists.infradead.org, David Woodhouse Subject: Re: [RFT][PATCH] b43: use 8K buffers for 64-bit DMA to workaround hardware bug References: <1314201438-12125-1-git-send-email-zajec5@gmail.com> <20110824180611.36af5a83@milhouse> In-Reply-To: <20110824180611.36af5a83@milhouse> Content-Type: text/plain; charset=UTF-8; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 08/24/2011 11:06 AM, Michael Büsch wrote: > On Wed, 24 Aug 2011 17:57:18 +0200 > Rafał Miłecki wrote: > >> + /* For unknown reasons - possibly a hardware error - the BCM4311 rev >> * 02, which uses 64-bit DMA, needs the ring buffer in very low memory, >> * which accounts for the GFP_DMA flag below. >> - * >> - * The flags here must match the flags in free_ringmemory below! >> */ >> + gfp_t flags = GFP_KERNEL; >> if (ring->type == B43_DMA_64BIT) >> flags |= GFP_DMA; > > > Did somebody actually re-evaluate this? > I still believe that this is not a hardware error, but rather a software > bug in the DMA allocator that probably is fixed already. > > Larry, I think you added this. Do you still have the device that triggered this? Yes, I do. I'll test the BCM4311 with the GFP_KERNEL flag. Larry