Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754825Ab1CQRf6 (ORCPT ); Thu, 17 Mar 2011 13:35:58 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:58967 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751576Ab1CQRf4 convert rfc822-to-8bit (ORCPT ); Thu, 17 Mar 2011 13:35:56 -0400 MIME-Version: 1.0 In-Reply-To: References: <4D81D6F9.3040304@t-online.de> From: Linus Torvalds Date: Thu, 17 Mar 2011 10:33:04 -0700 Message-ID: Subject: Re: [BUG][2.6.38] IRQ Lock Inversion / i915 fails To: Takashi Iwai Cc: Knut Petersen , Jaroslav Kysela , Chris Wilson , jesse.barnes@intel.com, gregkh@suse.de, linux-kernel@vger.kernel.org, =?ISO-8859-1?Q?David_M=FCller?= Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1043 Lines: 27 On Thu, Mar 17, 2011 at 10:15 AM, Takashi Iwai wrote: > > The trigger callback should be called always in irq-disabled context, > so this should be OK. Oh, ok. I missed the snd_pcm_action_lock_irq() thing disabling interrupts in that call sequence.. >?But loopback_pos_update() is called in the > timer callback, and this can be the issue. Hmm. If the timer callback is the only other case doing that, then that should be ok. In fact, now that I look at that lockdep thing, I'm confused. Where does the hard irq come in at all for that lock? It seems to come from self_group.lock, but I don't see why/how they nest. That said, the sound locking is odd, I'm sure you see it. But a commentary about how this came about in the changelog would be good. Linus -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/