Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763145AbZFPVTz (ORCPT ); Tue, 16 Jun 2009 17:19:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754406AbZFPVTq (ORCPT ); Tue, 16 Jun 2009 17:19:46 -0400 Received: from mga11.intel.com ([192.55.52.93]:54073 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751788AbZFPVTp (ORCPT ); Tue, 16 Jun 2009 17:19:45 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.42,232,1243839600"; d="scan'208";a="466988182" Subject: Re: 2.6.30: hibernation/swsusp lockup due to acpi-cpufreq From: "Pallipadi, Venkatesh" To: Andrew Morton Cc: Johannes Stezenbach , "rjw@sisk.pl" , "linux-kernel@vger.kernel.org" , "davej@redhat.com" , "pavel@ucw.cz" , "linux-acpi@vger.kernel.org" , "lenb@kernel.org" , "arjan@infradead.org" , "tglx@linutronix.de" , benh@kernel.crashing.org In-Reply-To: <20090616140923.eb3ae6e3.akpm@linux-foundation.org> References: <20090615232709.GA6059@sig21.net> <200906160216.29537.rjw@sisk.pl> <20090616142217.GA5548@sig21.net> <20090616115540.ceb67a30.akpm@linux-foundation.org> <20090616195750.GA12814@sig21.net> <20090616202558.GA5423@linux-os.sc.intel.com> <20090616204039.GA13399@sig21.net> <20090616140923.eb3ae6e3.akpm@linux-foundation.org> Content-Type: text/plain Date: Tue, 16 Jun 2009 14:18:10 -0700 Message-Id: <1245187090.4534.7423.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.24.3 (2.24.3-1.fc10) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4252 Lines: 107 On Tue, 2009-06-16 at 14:09 -0700, Andrew Morton wrote: > On Tue, 16 Jun 2009 22:40:39 +0200 > Johannes Stezenbach wrote: > > > On Tue, Jun 16, 2009 at 01:25:58PM -0700, Pallipadi, Venkatesh wrote: > > > > > > Can you try the patch below (your changes + a warnon). That should give > > > the stack trace with successful suspend-resume. > > > > > > acpi-cpufreq will not directly disable interrupt and call these routines. > > > So, it will be interesting to see how we are ending up in this state. > > > > Yes, I actually had the same idea and just did it ;-) > > I also found this: > > http://lkml.org/lkml/2007/7/17/674 > > > > ------------[ cut here ]------------ > > WARNING: at kernel/up.c:18 smp_call_function_single+0x45/0x60() > > Hardware name: 2373Y4M > > Modules linked in: ath5k mac80211 cfg80211 uhci_hcd ehci_hcd > > Pid: 4139, comm: bash Not tainted 2.6.30 #8 > > Call Trace: > > [] warn_slowpath_common+0x60/0x90 > > [] ? do_drv_read+0x0/0x31 > > [] warn_slowpath_null+0xd/0x10 > > [] smp_call_function_single+0x45/0x60 > > [] get_cur_val+0x62/0x6c > > [] get_cur_freq_on_cpu+0x35/0x58 > > [] cpufreq_suspend+0x76/0xd9 > > [] ? clockevents_notify+0x1e/0x68 > > [] sysdev_suspend+0x4e/0x182 > > [] hibernation_snapshot+0x89/0x16b > > [] hibernate+0x8f/0x147 > > [] ? state_store+0x0/0xa2 > > [] state_store+0x55/0xa2 > > [] ? state_store+0x0/0xa2 > > [] kobj_attr_store+0x1a/0x22 > > [] sysfs_write_file+0xb4/0xdf > > [] ? sysfs_write_file+0x0/0xdf > > [] vfs_write+0x8a/0x12c > > [] sys_write+0x3b/0x60 > > [] sysenter_do_call+0x12/0x26 > > ---[ end trace 1c2172bce3982a59 ]--- > > Right, so it's the suspend-must-disable-local-interrupts thing. Again. > create_image()'s local_irq_disable(). > > It was wrong to call work_on_cpu() with lcoal interrupts disabled, and > it's now wrong to call smp_call_function_single() with local interrupts > disabled. It's just that smp_call_function_single() warns while > work_on_cpu() didn't. > > That all explains the warning But afaik we still don't know why your > machine actually failed. Perhaps it is a side-efect of emitting the > warning when the console is in a weird state? > > So.. what to do? Possibly we could hack cpufreq to not use > smp_call_function_single() if the call is to be done on the local CPU. > But SMP might still be broken - if it really does want to do a cross-cpu > call. We surely do not need cross CPU cal at this point as all secondary cpus will be offline at this point. > Why does cpufreq need to do a cross-CPU get_cur_freq_on_cpu() call at > suspend time _anyway_? Surely cpufreq knows the target CPU's frequency > from its internal in-main-memory state? That was what I was wondering as well. Looks like this part of cpufreq_suspend came from commit 42d4dc3f4e1ec1396371aac89d0dccfdd977191b Author: Benjamin Herrenschmidt Date: Fri Apr 29 07:40:12 2005 -0700 [PATCH] Add suspend method to cpufreq core In order to properly fix some issues with cpufreq vs. sleep on PowerBooks, I had to add a suspend callback to the pmac_cpufreq driver. I must force a switch to full speed before sleep and I switch back to previous speed on resume. I also added a driver flag to disable the warnings in suspend/resume since it is expected in this case to have different speed (and I want it to fixup the jiffies properly). Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds benh: Do you think we still need this cpufreq_driver->get() and return error on (!cur_freq || !cpu_policy->cur) stuff? May be we should all the checks only if CPUFREQ_PM_NO_WARN is set? Thanks, Venki -- 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/