Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758172Ab2HUQuP (ORCPT ); Tue, 21 Aug 2012 12:50:15 -0400 Received: from mga11.intel.com ([192.55.52.93]:7400 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758133Ab2HUQuM (ORCPT ); Tue, 21 Aug 2012 12:50:12 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.77,803,1336374000"; d="scan'208";a="207642873" Date: Wed, 22 Aug 2012 00:50:06 +0800 From: Fengguang Wu To: Michael Wang Cc: Thomas Gleixner , Yinghai Lu , Suresh Siddha , LKML Subject: Re: BUG: scheduling while atomic, under native_smp_prepare_cpus() Message-ID: <20120821165006.GA24559@localhost> References: <20120817134944.GA539@localhost> <50320163.5080703@linux.vnet.ibm.com> <20120820092744.GA3668@localhost> <5032067E.20505@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5032067E.20505@linux.vnet.ibm.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1523 Lines: 47 On Mon, Aug 20, 2012 at 05:42:22PM +0800, Michael Wang wrote: > On 08/20/2012 05:27 PM, Fengguang Wu wrote: > > Hi Michael, > > > > On Mon, Aug 20, 2012 at 05:20:35PM +0800, Michael Wang wrote: > >> On 08/17/2012 09:49 PM, Fengguang Wu wrote: > >> > >> Hi, FengGuang > >> > >> native_smp_prepare_cpus has already disabled the preempt before > >> reach __irq_alloc_descs(), and sleep in mutex_lock() cause the bug. > >> > >> May be the follow patch could help to solve the issue(actually I > >> think the true problem should be in _cond_resched...). > > > > Is this a debug patch? Since what it does is to conditionally disable > > the warning. > > No, I use this as a solution, it should work as the bug reported in boot > process before init_post called. > > We have some reference from __might_sleep which also avoid the check if > system has not fully booted, so I think this way is acceptable, but I'm > not the one to make decision... Fair enough. > > > >> I can't do test by my self since I can't reproduce the issue on my > >> machine, the kernel_init thread never got a need sched flag set at > >> that moment in my case... > > > > I'll try it and report back :) > > Appreciate :) It works! :) Tested-by: Fengguang Wu Thanks, Fengguang -- 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/