From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263364AbTJZRpi (ORCPT ); Sun, 26 Oct 2003 12:45:38 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263367AbTJZRpi (ORCPT ); Sun, 26 Oct 2003 12:45:38 -0500 Received: from puetzk.org ([212.13.198.114]:61965 "EHLO puetzk.vm.65535.net") by vger.kernel.org with ESMTP id S263364AbTJZRph (ORCPT ); Sun, 26 Oct 2003 12:45:37 -0500 From: Kevin Puetz To: jjluza , linux-kernel@vger.kernel.org, Jaroslav Kysela Subject: Alsa deadlock fix (was Re: 2.6-test8 : alsa hangs my box) Date: Sun, 26 Oct 2003 11:45:18 -0600 User-Agent: KMail/1.5.9 MIME-Version: 1.0 Content-Disposition: inline Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Message-Id: <200310261145.18537.puetzk@puetzk.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org I am seeing this hang also, on a different card, whenever a native alsa and an OSS-emulation app collide. No nVidia stuff this time, and not snd_intel8x0 either, this is w/ a via82xx motherboard's integrated sound. From what little one can tell from the sysrq-T backtrace, it looks like a classic deadlock (both tasks stick in down(), probably on different mutexes). It also looks like it has alreay been fixed (in alsa 0.9.7b) - I think the kernel's alsa is approximately equivalent to 0.9.6 these days? So, it looks like either some work to port that patch or a wholesale merge of alsa 0.9.8 would be good before 2.6.0... probably the former given Linus's strongly-worded comments with -test9 :-) But a deadlock that results in two unkillable state 'D' processes whenever you an OSS and an alsa-native app access the soundcard at the same time, which happens on both VIA and Intel integrated sound, seems like a hang which might meet his criteria of problems which "causes lockups or just basic nonworkingness: and this happens on hardware that normal people are expected to have". So I figured it's worth asking if someone who already knows what the fix consisted of could push it toward Linus ...