From mboxrd@z Thu Jan 1 00:00:00 1970 From: rui.zhang@intel.com (Zhang Rui) Date: Sat, 05 Nov 2016 19:39:32 +0800 Subject: [Bug] ARM: mxs: STI: console can't wake up from freeze In-Reply-To: <322177156.158733.9867e3e7-5710-4844-a098-6f44bd852a6d.open-xchange@email.1und1.de> References: <315017958.66634.5d4fc19c-31cd-4900-8613-af4cadec5da4.open-xchange@email.1und1.de> <20161023133134.GI1041@n2100.armlinux.org.uk> <1709157673.85170.1cb53b4d-2805-48ea-aef1-dd282306d108.open-xchange@email.1und1.de> <20161031161700.GH1041@n2100.armlinux.org.uk> <847975190.29034.38a9c7fa-bdf8-4732-ac8b-cf15c21e3ce8.open-xchange@email.1und1.de> <20161101092304.GM1041@n2100.armlinux.org.uk> <322177156.158733.9867e3e7-5710-4844-a098-6f44bd852a6d.open-xchange@email.1und1.de> Message-ID: <1478345972.2206.15.camel@intel.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Sat, 2016-11-05 at 12:07 +0100, Stefan Wahren wrote: > Hi, > > [add Rui] > > > > > Russell King - ARM Linux hat am 1. November > > 2016 um > > 10:23 geschrieben: > > > > > > On Mon, Oct 31, 2016 at 08:54:33PM +0100, Stefan Wahren wrote: > > > > > > [??366.696043] INFO: task ext4lazyinit:70 blocked for more than > > > 120 seconds. > > > [??366.703046]???????Not tainted 4.9.0-rc1 #7 > > > [??366.707188] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" > > > disables > > > this > > > message. > > > [??366.715161] ext4lazyinit????D c05aa6ac?????0????70??????2 > > > 0x00000000 > > This looks like a very different problem - I guess one for ext4 > > people. > > > i investigated the issue more further. This trace wasn't > representative, because > the stacktrace is different in most cases. The "endless loop" is > located in > freeze_enter(). So i added some debug messages: > is this a regression? > -------------------------------->8----------------------------------- > - > diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c > index 1e7f5da..079c08d 100644 > --- a/kernel/power/suspend.c > +++ b/kernel/power/suspend.c > @@ -67,17 +67,20 @@ static void freeze_enter(void) > ? spin_unlock_irq(&suspend_freeze_lock); > ? > ? get_online_cpus(); > + pr_info("PM: calling cpuidle_resume()\n"); > ? cpuidle_resume(); > ? > ? /* Push all the CPUs into the idle loop. */ > + pr_info("PM: calling wake_up_all_idle_cpus()\n"); > ? wake_up_all_idle_cpus(); > - pr_debug("PM: suspend-to-idle\n"); > + pr_info("PM: suspend-to-idle\n"); > ? /* Make the current CPU wait so it can enter the idle loop > too. */ > ? wait_event(suspend_freeze_wait_head, > ? ???suspend_freeze_state == FREEZE_STATE_WAKE); > - pr_debug("PM: resume from suspend-to-idle\n"); > + pr_info("PM: resume from suspend-to-idle\n"); > ? > ? cpuidle_pause(); > + pr_info("PM: called cpuidle_pause()\n"); > ? put_online_cpus(); > ? > ? spin_lock_irq(&suspend_freeze_lock); > @@ -91,6 +94,8 @@ void freeze_wake(void) > ?{ > ? unsigned long flags; > ? > + pr_info("PM: freeze_wake()\n"); > + > ? spin_lock_irqsave(&suspend_freeze_lock, flags); > ? if (suspend_freeze_state > FREEZE_STATE_NONE) { > ? suspend_freeze_state = FREEZE_STATE_WAKE; > > -------------------------------->8----------------------------------- > - > > and repeated the test cases for freeze which shows none the > representative > stacktraces: > > 1. cmdline contains no_console_suspend > > * echo freeze > /sys/power/state > > ... > [??139.371308] PM: suspend of devices complete after 1342.721 msecs > [??139.385203] PM: late suspend of devices complete after 7.668 msecs > [??139.399428] PM: noirq suspend of devices complete after 7.936 > msecs > [??139.406639] PM: calling cpuidle_resume() > [??139.410619] PM: calling wake_up_all_idle_cpus() > [??139.415339] PM: suspend-to-idle > > > > > > > > > > > > > > no reaction to input via Debug UART > [??366.683570] INFO: task bash:373 blocked for more than 120 seconds. > [??366.689814]???????Not tainted 4.9.0-rc1-dirty #14 > [??366.694705] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" > disables this > message. > [??366.702685] bash????????????D c05aa6ec?????0???373????275 > 0x00000000 > [??366.709227] [] (__schedule) from [] > (schedule+0x3c/0xbc) > [??366.716495] [] (schedule) from [] > (suspend_devices_and_enter+0x888/0xa78) > [??366.725228] [] (suspend_devices_and_enter) from > [] > (pm_suspend+0x72c/0x81c) > [??366.734150] [] (pm_suspend) from [] > (state_store+0x80/0xcc) > [??366.741554] [] (state_store) from [] > (kobj_attr_store+0x18/0x1c) > [??366.749515] [] (kobj_attr_store) from [] > (sysfs_kf_write+0x48/0x4c) > [??366.757735] [] (sysfs_kf_write) from [] > (kernfs_fop_write+0xfc/0x1d0) > [??366.766130] [] (kernfs_fop_write) from [] > (__vfs_write+0x2c/0x124) > [??366.774255] [] (__vfs_write) from [] > (vfs_write+0xb4/0x1a4) > [??366.781640] [] (vfs_write) from [] > (SyS_write+0x44/0x88) > [??366.788890] [] (SyS_write) from [] > (ret_fast_syscall+0x0/0x1c) > [??366.796627] > [??366.796627] Showing all locks held in the system: > [??366.803011] 2 locks held by khungtaskd/10: > [??366.807149]??#0: [??366.808931]??( > rcu_read_lock[??366.811784] ){......} > , at: [??366.814813] [] watchdog+0xb4/0x61c > [??366.819128]??#1: [??366.820902]??( > tasklist_lock[??366.823876] ){.+.+..} > , at: [??366.826765] [] debug_show_all_locks+0x28/0x1bc > [??366.832151] 4 locks held by bash/373: > [??366.835973]??#0: [??366.837765]??( > sb_writers[??366.840365] #4 > ){.+.+.+}[??366.842987] , at: > [??366.845079] [] vfs_write+0x194/0x1a4 > [??366.849551]??#1: [??366.851324]??( > &of->mutex[??366.854058] ){+.+.+.} > , at: [??366.856944] [] kernfs_fop_write+0xc0/0x1d0 > [??366.861941]??#2: [??366.863839]??( > s_active[??366.866288] #43 > ){.+.+.+}[??366.868877] , at: > [??366.870938] [] kernfs_fop_write+0xc8/0x1d0 > [??366.876053]??#3: [??366.877843]??( > pm_mutex[??366.880272] ){+.+.+.} > , at: [??366.883266] [] pm_suspend+0x90/0x81c > [??366.887757] > [??366.889268] ============================================= > [??366.889268] > > 2. cmdline contains no_console_suspend > > * echo enabled > /sys/class/tty/ttyAMA0/power/wakeup > * echo freeze > /sys/power/state > > the same as in 1. > > 3. cmdline doesn't contains no_console_suspend > > * echo enabled > /sys/class/tty/ttyAMA0/power/wakeup > * echo freeze > /sys/power/state > > [??161.093187] PM: Syncing filesystems ... [??161.734413] done. > [??161.793242] Freezing user space processes ... (elapsed 0.008 > seconds) done. > [??161.809797] Freezing remaining freezable tasks ... (elapsed 0.004 > seconds) > done. > [??161.821953] Suspending console(s) (use no_console_suspend to > debug) > > >? > > > > > no reaction to Debug UART Then the system does not have any response? or the system freezes and wakes up as expected? > I expected that in all 3 cases freeze_wake() will be called. Why not? > > Here my config again: > > CONFIG_PM_SLEEP=y > CONFIG_SUSPEND=y > CONFIG_SUSPEND_FREEZER=y > CONFIG_PM=y > CONFIG_CPU_IDLE is not set hmmm, why not have CONFIG_CPU_IDLE set? thanks, rui