Re: 4.10-rc1: thinkpad x60: who ate my cpu?

From: Woody Suwalski <terraluna977@gmail.com>
To: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>,
	kernel list <linux-kernel@vger.kernel.org>,
	tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com
Subject: Re: 4.10-rc1: thinkpad x60: who ate my cpu?
Date: Sun, 12 Feb 2017 20:35:13 -0500	[thread overview]
Message-ID: <161a3edb-84f1-769d-d8e9-04102ddbbe58@gmail.com> (raw)
In-Reply-To: <20170212195742.GA6264@amd>

Pavel Machek wrote:
> Hi!
>
>>> The kernel is 4.8.17 EOL, installed almost a month ago.
>>> Platform ThinkPad x60,  Intel(R) Core(TM) Duo CPU      T2400  @ 1.83GHz
>>>
>>> In dmesg I see that it used to be when 2 CPUs were OK:
>>> [690409.476107] PM: noirq suspend of devices complete after 79.914 msecs
>>> [690409.476547] ACPI: Preparing to enter system sleep state S3
>>> [690409.780081] ACPI : EC: EC stopped
>>> [690409.780083] PM: Saving platform NVS memory
>>> [690409.780284] Disabling non-boot CPUs ...
>>> [690409.805284] smpboot: CPU 1 is now offline
>>> [690409.816464] ACPI: Low-level resume complete
>>> [690409.816464] ACPI : EC: EC started
>>> [690409.816464] PM: Restoring platform NVS memory
>>> [690409.816464] Enabling non-boot CPUs ...
>>> [690409.840574] x86: Booting SMP configuration:
>>> [690409.840576] smpboot: Booting Node 0 Processor 1 APIC 0x1
>>> [690409.805271] Initializing CPU#1
>>> [690409.805271] Disabled fast string operations
>>> [690409.888252]  cache: parent cpu1 should not be sleeping
>>> [690409.920185] CPU1 is up
>>> [690409.922288] ACPI: Waking up from system sleep state S3
>>>
>>> Then the CPU1 failed to start:
>>>
>>> [691329.776108] PM: noirq suspend of devices complete after 79.941 msecs
>>> [691329.776550] ACPI: Preparing to enter system sleep state S3
>>> [691330.080081] ACPI : EC: EC stopped
>>> [691330.080083] PM: Saving platform NVS memory
>>> [691330.080284] Disabling non-boot CPUs ...
>>> [691330.105303] smpboot: CPU 1 is now offline
>>> [691330.116477] ACPI: Low-level resume complete
>>> [691330.116477] ACPI : EC: EC started
>>> [691330.116477] PM: Restoring platform NVS memory
>>> [691330.116477] Enabling non-boot CPUs ...
>>> [691330.140570] x86: Booting SMP configuration:
>>> [691330.140572] smpboot: Booting Node 0 Processor 1 APIC 0x1
>>> [691340.140015] smpboot: do_boot_cpu failed(-1) to wakeup CPU#1
>>> [691340.164445] Error taking CPU1 up: -5
>>> [691340.166309] ACPI: Waking up from system sleep state S3
>>>
>>> And now it is:
>>> [692517.868523] ACPI: Preparing to enter system sleep state S3
>>> [692518.172074] ACPI : EC: EC stopped
>>> [692518.172076] PM: Saving platform NVS memory
>>> [692518.172269] Disabling non-boot CPUs ...
>>> [692518.172269] ACPI: Low-level resume complete
>>> [692518.172269] ACPI : EC: EC started
>>> [692518.172269] PM: Restoring platform NVS memory
>>> [692518.172269] ACPI: Waking up from system sleep state S3
>>>
>>> Is there any test I could do on the CPU wakeup while in that state?
>>>
>> Is there a way to kick the offline-CPU into operation from /sys level?
> echo 0 > /sys/devices/system/cpu/cpu1/online
>
> should work. And... good thinking :-).
>
> 									Pavel
Did not work,
     echo 0 > /sys/devices/system/cpu/cpu1/online
     -su: echo: write error: Device or resource busy

However
     echo 1 > /sys/devices/system/cpu/cpu1/online
did not return an error ( but still only CPU0 seen)

Interesting experiment: I have hibernated and then woke up - and still 
only CPU0. I was expecting that after the power cycle the hotplug will 
bring CPU1 up...

Woody