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

[Woody Suwalski]

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