From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756940AbXIBJkF (ORCPT ); Sun, 2 Sep 2007 05:40:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754729AbXIBJjz (ORCPT ); Sun, 2 Sep 2007 05:39:55 -0400 Received: from gate.crashing.org ([63.228.1.57]:39113 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755112AbXIBJjy (ORCPT ); Sun, 2 Sep 2007 05:39:54 -0400 Subject: Re: BUG POWERPC: snd-powermac hangs since 'Merge 32 and 64 bits asm-powerpc/io.h' From: Benjamin Herrenschmidt To: Dave Vasilevsky Cc: tiwai@suse.de, linux-kernel@vger.kernel.org In-Reply-To: References: Content-Type: text/plain Date: Sun, 02 Sep 2007 11:40:14 +0200 Message-Id: <1188726014.5972.128.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.10.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2007-09-01 at 00:53 -0400, Dave Vasilevsky wrote: > When playing audio with the snd-powermac driver on a PowerMac G4 > Quicksilver (Tumbler audio) the sound hangs after a few seconds. > > - The time before a hang varies from one second to one minute. > - Killing the process playing sound and starting again will allow > sound to continue (for a few more seconds). > - Many different userspace audio systems and different audio sources > all encounter this bug--definitely a kernel issue. > - Vanilla kernels from 2.6.20 up to git HEAD show this behavior. > Others have reported this bug on distro kernels.[1][2] > > I used git-bisect to find that the regression first occured after git > commit 68a64357d15ae4f596e92715719071952006e83c > "powerpc: Merge 32 and 64 bits asm-powerpc/io.h" by benh.[3] > > My kernel debugging skills are admittedly limited, but I scattered > printks through some relevant files and found that audio stops just as > snd_pmac_pcm_update in sound/ppc/pmac.c encounters a struct dbdma_cmd > with xfer_status == 0x8088. Normally it should be 0x84 (ie: ACTIVE | > RUN) or 0x0. Hopefully this means something to somebody. I'm willing > to do more debugging if more information is necessary, kindly CC me on > replies to this message. .../... strange. I'm travelling at the moment. I'll try to have a look, but don't hesistate to "ping" me if you don't hear from me in the upcoming couple of weeks. Cheers, Ben.