From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030265AbWARHEa (ORCPT ); Wed, 18 Jan 2006 02:04:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030263AbWARHEa (ORCPT ); Wed, 18 Jan 2006 02:04:30 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:58077 "EHLO mx3.mail.elte.hu") by vger.kernel.org with ESMTP id S1030265AbWARHE3 (ORCPT ); Wed, 18 Jan 2006 02:04:29 -0500 Date: Wed, 18 Jan 2006 08:04:36 +0100 From: Ingo Molnar To: Andrew Morton Cc: michael@ellerman.id.au, serue@us.ibm.com, linuxppc64-dev@ozlabs.org, paulus@au1.ibm.com, anton@au1.ibm.com, linux-kernel@vger.kernel.org Subject: Re: 2.6.15-mm4 failure on power5 Message-ID: <20060118070436.GA24378@elte.hu> References: <20060116063530.GB23399@sergelap.austin.ibm.com> <200601180032.46867.michael@ellerman.id.au> <20060117140050.GA13188@elte.hu> <200601181119.39872.michael@ellerman.id.au> <20060118033239.GA621@cs.umn.edu> <20060118063732.GA21003@elte.hu> <20060117225304.4b6dd045.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060117225304.4b6dd045.akpm@osdl.org> User-Agent: Mutt/1.4.2.1i X-ELTE-SpamScore: 0.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=0.0 required=5.9 tests=AWL autolearn=no SpamAssassin version=3.0.3 0.0 AWL AWL: From: address is in the auto white-list X-ELTE-VirusStatus: clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Andrew Morton wrote: > > [ if this indeed is the case then i'll add irqs_off() checks to > > DEBUG_MUTEXES=y, to ensure that the mutex APIs are never called with > > interrupts disabled. ] > > Yes, I suppose so. But we're already calling might_sleep(), and > might_sleep() checks for that. Perhaps the might_sleep() check is > being defeated by the nasty system_running check. ah ... indeed. > There's a sad story behind that system_running check in might_sleep(). > Because the kernel early boot is running in an in_atomic() state, a > great number of bogus might_sleep() warnings come out because of > various code doing potentially-sleepy things. I ended up adding the > system_running test, with the changelog "OK, I give up. Kill all the > might_sleep warnings from the early boot process." Undoing that and > fixing up the fallout would be a lot of nasty work. OTOH, x86 was just fine last i checked, and it has alot more complex bootup code than any of the other architectures (due to the sheer number of x86 variants). Ingo