Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761961Ab2FVJ5V (ORCPT ); Fri, 22 Jun 2012 05:57:21 -0400 Received: from e28smtp01.in.ibm.com ([122.248.162.1]:42464 "EHLO e28smtp01.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761949Ab2FVJ5T (ORCPT ); Fri, 22 Jun 2012 05:57:19 -0400 Message-ID: <4FE44163.4060509@linux.vnet.ibm.com> Date: Fri, 22 Jun 2012 15:26:51 +0530 From: Deepthi Dharwar User-Agent: Mozilla/5.0 (X11; Linux i686; rv:11.0) Gecko/20120329 Thunderbird/11.0.1 MIME-Version: 1.0 To: wfg@linux.intel.com CC: "Rafael J. Wysocki" , LKML Subject: Re: boot hang on commit "PM / ACPI: Fix suspend/resume regression caused by cpuidle cleanup." References: <20120622073513.GA15864@localhost> In-Reply-To: <20120622073513.GA15864@localhost> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit x-cbid: 12062209-4790-0000-0000-0000035A58C3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6682 Lines: 193 Hi, This is interesting .. suspend fix breaking boot on kvm. We complied and booted fine with mainline kernels including 3.5-rc2 with this fix on servers and laptops. So wondering how different is booting on machines Vs from kvm ? Also, are you seeing smooth boot on kvm by reverting only this patch ? Cheers Deepthi On 06/22/2012 01:05 PM, wfg@linux.intel.com wrote: > Hi Deepthi, > > It seems that commit de08622 triggers a boot hang in my kvm boot test. > > kvm -cpu kvm64 -enable-kvm \ > -kernel ./gpxelinux.lkrn \ > -initrd ./kvm.gpxe \ > -m 384M \ > -net nic,vlan=0,macaddr=00:00:00:00:00:00,model=e1000 \ > -net user,vlan=0,hostfwd=tcp::$port-:22 \ > -boot order=nc \ > -no-reboot \ > -watchdog i6300esb \ > $(qemu_drives) \ > -pidfile $pidfile \ > -serial file:$dmesg > > tree: git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git linux-next > head: de08622731417ba429fc470ab8f2d7c260cb5c72 > commit: de08622731417ba429fc470ab8f2d7c260cb5c72 [9/9] PM / ACPI: Fix suspend/resume regression caused by cpuidle cleanup. > config: x86_64-allyesdebian (attached as .config) > > x86_64-allyesdebian bbbbbbbbbB > -- > 8: b 0eb8c06 2012-06-19 22:23:37 +0200 PM / Sleep: Separate printing suspend times from initcall_debug > 9: B de08622 boot hang after [ 81.370898] usbcore: registered new interface driver dw2102 > > legend: [b] boot fine [B] boot error > > commit de08622731417ba429fc470ab8f2d7c260cb5c72 > Author: Deepthi Dharwar > Date: Wed Jun 13 16:28:17 2012 +0530 > > PM / ACPI: Fix suspend/resume regression caused by cpuidle cleanup. > > Commit e978aa7d7d57d04eb5f88a7507c4fb98577def77 ( cpuidle: Move > dev->last_residency update to driver enter routine; remove dev->last_state) > was breaking suspend on laptops, as reported in the below link > - https://lkml.org/lkml/2011/11/11/164 > > This was fixed in commit 3439a8da16bcad6b0982ece938c9f8299bb53584 > (ACPI / cpuidle: Remove acpi_idle_suspend (to fix suspend regression) > by removing acpi_idle_suspend flag. > - https://lkml.org/lkml/2011/11/14/74 > > But this fix did not work on all systems > as Suspend/resume regression was reported on Lenovo S10-3 > recently by Dave. > - https://lkml.org/lkml/2012/5/27/115 > It looked like with commit e978aa7d broke suspend and > with commit 3439a8da resume was not working with acpi_idle driver. > > This patch fixes the regression that caused this issue > in the first place. acpi_idle_suspend flag is essential on > some x86 systems to prevent the cpus from going to deeper C-states > when suspend is triggered ( commit b04e7bdb984 ) > So reverting the commit 3439a8da is essential. > > By default, irqs are disabled in cpu_idle arch specific call > and re-enabled in idle state return path . As the acpi_idle_suspend > flag was being set during suspend, which prevented the cpus > going to deeper idle states, it is essential to > enabling the irqs in its return path too. > > To address the suspend issue, > we were not re-enabling the interrupts while returning from > acpi_idle_enter_bm() routine if acpi_idle_suspend flag is set. > and this was causing suspend failure. > > In addition to the above fix, a sanity check has also been added > in x86 arch specific cpu_idle call to ensure that the idle call > always returns with IRQs enabled. > > Signed-off-by: Deepthi Dharwar > Reported-and-Tested-by: Dav Hansen > Tested-by: Preeti Murthy > Reviewed-by: Srivatsa S Bhat > Signed-off-by: Rafael J. Wysocki > > diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c > index 735279e..8ab76ad 100644 > --- a/arch/x86/kernel/process.c > +++ b/arch/x86/kernel/process.c > @@ -460,6 +460,12 @@ void cpu_idle(void) > pm_idle(); > > rcu_idle_exit(); > + > + /* > + * Sanity check to ensure that idle call returns > + * with IRQs enabled > + */ > + WARN_ON(irqs_disabled()); > start_critical_timings(); > > /* In many cases the interrupt that ended idle > diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c > index f3decb3..c2ffd84 100644 > --- a/drivers/acpi/processor_idle.c > +++ b/drivers/acpi/processor_idle.c > @@ -224,6 +224,7 @@ static void lapic_timer_state_broadcast(struct acpi_processor *pr, > /* > * Suspend / resume control > */ > +static int acpi_idle_suspend; > static u32 saved_bm_rld; > > static void acpi_idle_bm_rld_save(void) > @@ -242,13 +243,21 @@ static void acpi_idle_bm_rld_restore(void) > > int acpi_processor_suspend(struct acpi_device * device, pm_message_t state) > { > + if (acpi_idle_suspend == 1) > + return 0; > + > acpi_idle_bm_rld_save(); > + acpi_idle_suspend = 1; > return 0; > } > > int acpi_processor_resume(struct acpi_device * device) > { > + if (acpi_idle_suspend == 0) > + return 0; > + > acpi_idle_bm_rld_restore(); > + acpi_idle_suspend = 0; > return 0; > } > > @@ -754,6 +763,12 @@ static int acpi_idle_enter_c1(struct cpuidle_device *dev, > > local_irq_disable(); > > + if (acpi_idle_suspend) { > + local_irq_enable(); > + cpu_relax(); > + return -EINVAL; > + } > + > lapic_timer_state_broadcast(pr, cx, 1); > kt1 = ktime_get_real(); > acpi_idle_do_entry(cx); > @@ -823,6 +838,12 @@ static int acpi_idle_enter_simple(struct cpuidle_device *dev, > > local_irq_disable(); > > + if (acpi_idle_suspend) { > + local_irq_enable(); > + cpu_relax(); > + return -EINVAL; > + } > + > if (cx->entry_method != ACPI_CSTATE_FFH) { > current_thread_info()->status &= ~TS_POLLING; > /* > @@ -901,6 +922,13 @@ static int acpi_idle_enter_bm(struct cpuidle_device *dev, > if (unlikely(!pr)) > return -EINVAL; > > + if (acpi_idle_suspend) { > + if (irqs_disabled()) > + local_irq_enable(); > + cpu_relax(); > + return -EINVAL; > + } > + > if (!cx->bm_sts_skip && acpi_idle_bm_check()) { > if (drv->safe_state_index >= 0) { > return drv->states[drv->safe_state_index].enter(dev, -- 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/