Re: Oops after resume from suspend

Avi Kivity
2007-01-26T18:12:16Z

> Avi Kivity wrote:
>> Jeremy Katz wrote:
>>> When using kvm on my laptop, I get the following oops if I try using
>>> kvm
>>> after a suspend (ACPI S3)/resume cycle. At first I thought it went
>>> away
>>> if I unloaded the module before suspending and then reloading it
>>> afterwards, but I can't reproduce that working now, so I might have
>>> just
>>> been hallucinating. Thoughts of things to try?
>>
>> Module unload/reload should work. Can you try adding printks in
>> hardware_disable() and hardware_enable()?
>
> Okay, what was going wrong with reloading was the difference between -
> and _ with module naming :-/ *sigh* Actually getting the module
> unloaded then makes things work fine.

I was bitten by this too...

>
>> For real suspend support, we need to flush any cached state on Intel
>> cpus (vmcs_clear), and to do the hardware_disable()/hardware_enable()
>> cycle. Should be easy.
>
> The obvious approach (attached) fails to resume -- there may be
> console output, but hard to tell on my laptop. I'll dig up a box with
> a serial port to try there and see if I get something across serial
> console with it.

It also needs cpu hotplug support, and some work to decache the vmcs on
Intel hosts. I have this three-quarters working now.

--
Do not meddle in the internals of kernels, for they are subtle and quick to panic.