Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933196Ab3GPPXJ (ORCPT ); Tue, 16 Jul 2013 11:23:09 -0400 Received: from e23smtp09.au.ibm.com ([202.81.31.142]:54142 "EHLO e23smtp09.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932864Ab3GPPXG (ORCPT ); Tue, 16 Jul 2013 11:23:06 -0400 Message-ID: <51E56482.7020608@linux.vnet.ibm.com> Date: Tue, 16 Jul 2013 20:49:30 +0530 From: "Srivatsa S. Bhat" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120828 Thunderbird/15.0 MIME-Version: 1.0 To: Sergey Senozhatsky , "Rafael J. Wysocki" CC: Michael Wang , Jiri Kosina , Borislav Petkov , Viresh Kumar , linux-kernel@vger.kernel.org, cpufreq@vger.kernel.org, linux-pm@vger.kernel.org, Bartlomiej Zolnierkiewicz , Peter Wu Subject: Re: [LOCKDEP] cpufreq: possible circular locking dependency detected References: <20130710231305.GA4046@swordfish> <51DE1BE1.3090707@linux.vnet.ibm.com> <20130714114721.GB2178@swordfish> <20130714120629.GA4067@swordfish> <51E37194.1080103@linux.vnet.ibm.com> <51E3AA3B.9090003@linux.vnet.ibm.com> <20130715082918.GA2435@swordfish> <51E3F6EB.2050807@linux.vnet.ibm.com> <20130715232057.GA2486@swordfish> <51E50570.8080704@linux.vnet.ibm.com> <20130716104400.GA2359@swordfish.minsk.epam.com> In-Reply-To: <20130716104400.GA2359@swordfish.minsk.epam.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13071702-3568-0000-0000-000003EF2620 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10143 Lines: 217 On 07/16/2013 04:14 PM, Sergey Senozhatsky wrote: > On (07/16/13 14:03), Srivatsa S. Bhat wrote: >>>> So here is the solution: >>>> >>>> On 3.11-rc1, apply these patches in the order mentioned below, and check >>>> whether it fixes _all_ problems (both the warnings about IPI as well as the >>>> lockdep splat). >>>> >>>> 1. Patch given in: https://lkml.org/lkml/2013/7/11/661 >>>> (Just apply patch 1, not the entire patchset). >>>> >>>> 2. Apply the patch shown below, on top of the above patch: >>>> >>>> --------------------------------------------------------------------------- >>>> >>> >>> Hello Srivatsa, >>> Thanks, I'll test a bit later -- in the morning. (laptop stopped resuming from >>> suspend, probably radeon dmp). >>> >>> >> >> Sure, thanks! >> >>> >>> Shouldn't we also kick the console lock? >>> >>> >>> kernel/printk.c | 3 +++ >>> 1 file changed, 3 insertions(+) >>> >>> diff --git a/kernel/printk.c b/kernel/printk.c >>> index d37d45c..3e20233 100644 >>> --- a/kernel/printk.c >>> +++ b/kernel/printk.c >>> @@ -1926,8 +1926,11 @@ static int __cpuinit console_cpu_notify(struct notifier_block *self, >>> { >>> switch (action) { >>> case CPU_ONLINE: >>> + case CPU_ONLINE_FROZEN: >>> case CPU_DEAD: >>> + case CPU_DEAD_FROZEN: >>> case CPU_DOWN_FAILED: >>> + case CPU_DOWN_FAILED_FROZEN: >>> case CPU_UP_CANCELED: >>> console_lock(); >>> console_unlock(); >>> >>> >> >> No need. suspend_console() and resume_console() already handle it >> properly in the suspend/resume case, from what I can see. >> > > I've managed to wake up my laptop from suspend, and something's not right. > > > # for i in {1..5}; do \ > echo 0 > /sys/devices/system/cpu/cpu3/online; \ > echo 0 > /sys/devices/system/cpu/cpu2/online; \ > echo 1 > /sys/devices/system/cpu/cpu3/online; \ > echo 0 > /sys/devices/system/cpu/cpu1/online; \ > echo 1 > /sys/devices/system/cpu/cpu1/online; \ > echo 1 > /sys/devices/system/cpu/cpu2/online; \ > done > # systemctl suspend > -> resume > > > [ 227.329656] ACPI: Preparing to enter system sleep state S3 > [ 227.353334] PM: Saving platform NVS memory > > [ 227.355403] ====================================================== > [ 227.355404] [ INFO: possible circular locking dependency detected ] > [ 227.355407] 3.11.0-rc1-dbg-01398-gf537e41-dirty #1838 Not tainted > [ 227.355408] ------------------------------------------------------- > [ 227.355411] systemd-sleep/2280 is trying to acquire lock: > [ 227.355426] (cpu_add_remove_lock){+.+.+.}, at: [] > disable_nonboot_cpus+0x24/0x120 > [ 227.355427] > but task is already holding lock: > [ 227.355434] (console_lock){+.+.+.}, at: [] > suspend_console+0x26/0x40 > [ 227.355435] > which lock already depends on the new lock. > > [ 227.355436] > the existing dependency chain (in reverse order) is: > [ 227.355441] > -> #2 (console_lock){+.+.+.}: > [ 227.355448] [] lock_acquire+0xa4/0x200 > [ 227.355452] [] console_lock+0x77/0x80 > [ 227.355456] [] console_cpu_notify+0x31/0x40 > [ 227.355462] [] notifier_call_chain+0x5d/0x110 > [ 227.355466] [] __raw_notifier_call_chain+0xe/0x10 > [ 227.355469] [] cpu_notify+0x23/0x50 > [ 227.355473] [] cpu_notify_nofail+0xe/0x20 > [ 227.355482] [] _cpu_down+0x1ad/0x330 > [ 227.355486] [] cpu_down+0x36/0x50 > [ 227.355493] [] cpu_subsys_offline+0x1d/0x30 > [ 227.355498] [] device_offline+0x95/0xc0 > [ 227.355502] [] store_online+0x42/0x90 > [ 227.355506] [] dev_attr_store+0x18/0x30 > [ 227.355513] [] sysfs_write_file+0xdb/0x150 > [ 227.355517] [] vfs_write+0xbd/0x1e0 > [ 227.355522] [] SyS_write+0x4c/0xa0 > [ 227.355527] [] tracesys+0xd0/0xd5 > [ 227.355531] > -> #1 (cpu_hotplug.lock){+.+.+.}: > [ 227.355535] [] lock_acquire+0xa4/0x200 > [ 227.355541] [] mutex_lock_nested+0x67/0x410 > [ 227.355545] [] cpu_hotplug_begin+0x2b/0x60 > [ 227.355549] [] _cpu_up+0x2a/0x170 > [ 227.355552] [] cpu_up+0x59/0x80 > [ 227.355558] [] smp_init+0x64/0x95 > [ 227.355566] [] kernel_init_freeable+0x84/0x191 > [ 227.355570] [] kernel_init+0xe/0x180 > [ 227.355574] [] ret_from_fork+0x7c/0xb0 > [ 227.355578] > -> #0 (cpu_add_remove_lock){+.+.+.}: > [ 227.355582] [] __lock_acquire+0x1766/0x1d30 > [ 227.355586] [] lock_acquire+0xa4/0x200 > [ 227.355590] [] mutex_lock_nested+0x67/0x410 > [ 227.355594] [] disable_nonboot_cpus+0x24/0x120 > [ 227.355601] [] suspend_devices_and_enter+0x1f3/0x680 > [ 227.355605] [] pm_suspend+0x1d2/0x240 > [ 227.355609] [] state_store+0x79/0xf0 > [ 227.355614] [] kobj_attr_store+0xf/0x20 > [ 227.355618] [] sysfs_write_file+0xdb/0x150 > [ 227.355621] [] vfs_write+0xbd/0x1e0 > [ 227.355624] [] SyS_write+0x4c/0xa0 > [ 227.355628] [] tracesys+0xd0/0xd5 > [ 227.355629] > other info that might help us debug this: > > [ 227.355635] Chain exists of: > cpu_add_remove_lock --> cpu_hotplug.lock --> console_lock > > [ 227.355637] Possible unsafe locking scenario: > > [ 227.355638] CPU0 CPU1 > [ 227.355639] ---- ---- > [ 227.355642] lock(console_lock); > [ 227.355644] lock(cpu_hotplug.lock); > [ 227.355647] lock(console_lock); > [ 227.355650] lock(cpu_add_remove_lock); > [ 227.355651] > *** DEADLOCK *** > > [ 227.355653] 5 locks held by systemd-sleep/2280: > [ 227.355661] #0: (sb_writers#6){.+.+.+}, at: [] vfs_write+0x1bb/0x1e0 > [ 227.355668] #1: (&buffer->mutex){+.+.+.}, at: [] sysfs_write_file+0x3c/0x150 > [ 227.355676] #2: (s_active#110){.+.+.+}, at: [] sysfs_write_file+0xc3/0x150 > [ 227.355683] #3: (pm_mutex){+.+.+.}, at: [] pm_suspend+0x32/0x240 > [ 227.355690] #4: (console_lock){+.+.+.}, at: [] suspend_console+0x26/0x40 > [ 227.355691] > stack backtrace: > [ 227.355695] CPU: 0 PID: 2280 Comm: systemd-sleep Not tainted 3.11.0-rc1-dbg-01398-gf537e41-dirty #1838 > [ 227.355697] Hardware name: Acer Aspire 5741G /Aspire 5741G , BIOS V1.20 02/08/2011 > [ 227.355703] ffffffff82208680 ffff88015151bbc8 ffffffff81603038 ffffffff822073f0 > [ 227.355707] ffff88015151bc08 ffffffff815ffdaa ffff880153389fa0 ffff88015338a788 > [ 227.355712] 1d81e4832c04c441 ffff88015338a760 ffff88015338a788 ffff880153389fa0 > [ 227.355713] Call Trace: > [ 227.355719] [] dump_stack+0x4e/0x82 > [ 227.355723] [] print_circular_bug+0x2b6/0x2c5 > [ 227.355727] [] __lock_acquire+0x1766/0x1d30 > [ 227.355733] [] ? walk_system_ram_range+0x5c/0x140 > [ 227.355737] [] ? mark_held_locks+0x94/0x140 > [ 227.355741] [] lock_acquire+0xa4/0x200 > [ 227.355745] [] ? disable_nonboot_cpus+0x24/0x120 > [ 227.355749] [] ? disable_nonboot_cpus+0x24/0x120 > [ 227.355753] [] mutex_lock_nested+0x67/0x410 > [ 227.355757] [] ? disable_nonboot_cpus+0x24/0x120 > [ 227.355761] [] ? mutex_unlock+0xe/0x10 > [ 227.355768] [] ? acpi_os_get_iomem+0x4c/0x54 > [ 227.355772] [] disable_nonboot_cpus+0x24/0x120 > [ 227.355777] [] suspend_devices_and_enter+0x1f3/0x680 > [ 227.355780] [] ? printk+0x67/0x69 > [ 227.355785] [] pm_suspend+0x1d2/0x240 > [ 227.355789] [] state_store+0x79/0xf0 > [ 227.355792] [] kobj_attr_store+0xf/0x20 > [ 227.355796] [] sysfs_write_file+0xdb/0x150 > [ 227.355799] [] vfs_write+0xbd/0x1e0 > [ 227.355804] [] ? fget_light+0x320/0x4b0 > [ 227.355808] [] SyS_write+0x4c/0xa0 > [ 227.355811] [] tracesys+0xd0/0xd5 > [ 227.355814] Disabling non-boot CPUs ... > [ 227.357731] smpboot: CPU 1 is now offline > [ 227.461072] smpboot: CPU 2 is now offline > [ 227.565119] smpboot: CPU 3 is now offline > > This also looks like a different issue altogether, and IMHO deserves attention in a separate, dedicated email thread. Can you post it in a new thread please? Also, since you didn't get the original lockdep warning you reported, and since you didn't hit the IPI-to-offline-cpus warnings as well, I think we can safely conclude that my patches fixed your original problem. Rafael, could you kindly pick up this second patch[2] as well (with CC to stable)? (I'm aware that you already picked up the first one[1]). Thanks a lot! Regards, Srivatsa S. Bhat [1]. https://lkml.org/lkml/2013/7/11/661 [2]. http://marc.info/?l=linux-kernel&m=137389460805002&w=2 -- 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/