From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx1.redhat.com ([209.132.183.28]:3515 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758600Ab1EMMj2 (ORCPT ); Fri, 13 May 2011 08:39:28 -0400 Date: Fri, 13 May 2011 14:39:13 +0200 From: Stanislaw Gruszka To: Johannes Berg Cc: Jorge Miguel , linux-wireless@vger.kernel.org Subject: Re: Setting my WiFi adhoc connection in power save mode Message-ID: <20110513123913.GD5516@redhat.com> (sfid-20110513_143932_475023_6D18CF2E) References: <20110513115030.GB5516@redhat.com> <1305287703.3487.16.camel@jlt3.sipsolutions.net> <20110513122235.GC5516@redhat.com> <1305289642.3487.18.camel@jlt3.sipsolutions.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1305289642.3487.18.camel@jlt3.sipsolutions.net> Sender: linux-wireless-owner@vger.kernel.org List-ID: On Fri, May 13, 2011 at 02:27:22PM +0200, Johannes Berg wrote: > > > Deliberate. On some platforms/systems, the way the device goes to sleep > > > caused DMA trouble or something like that, and the ucode would sysassert > > > when it tried to wake itself up. The problem was fairly rare, but of > > > course the device wakes up 10 times a second or so ... > > > > It's interesting if PS on 3945 ever works or was broken from very > > beginning. I bet it was, on some old kernel, and this issue is similar > > case like most of other bugs we have in iwlwifi - something that worked > > well was broken by adding new chipsets/features support, but never fixed > > again and just masked/disabled instead. > > I doubt it, iirc it was just some DMA issue that was discovered at some > point and nobody could really pinpoint it. Those old devices stored some > internal data into a host memory buffer, and reading them back sometimes > corrupted them. Ok, so I will probably not try to reenable PS (as long someone clearly state that it works in the past, and this is a regression). Does this problem happen on both 4965 and 3945 ? Stanislaw