From mboxrd@z Thu Jan 1 00:00:00 1970 From: Larry Finger Date: Thu, 25 Aug 2011 12:29:50 -0500 Subject: [RFC/RFT] b43: Relax requirement for descriptors to be in the DMA zone In-Reply-To: References: <4e55750c.GPPIrbNLynUMWY/U%Larry.Finger@lwfinger.net> Message-ID: <4E56868E.7010404@lwfinger.net> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: =?UTF-8?B?UmFmYcWCIE1pxYJlY2tp?= Cc: John W Linville , Michael Buesch , b43-dev@lists.infradead.org, linux-wireless@vger.kernel.org On 08/25/2011 12:24 PM, Rafa? Mi?ecki 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