Re: kvm: odd time values since "kvmclock: set scheduler clock stable"

[Sasha Levin]

On 05/18/2015 06:39 PM, Marcelo Tosatti wrote:
> On Tue, May 12, 2015 at 07:17:24PM -0400, Sasha Levin wrote:
>> Hi all,
>>
>> I'm seeing odd jump in time values during boot of a KVM guest:
>>
>> [...]
>> [    0.000000] tsc: Detected 2260.998 MHz processor
>> [3376355.247558] Calibrating delay loop (skipped) preset value..
>> [...]
>>
>> I've bisected it to:
> 
> Paolo, Sasha,
> 
> Although this might seem undesirable, there is no requirement 
> for sched_clock to initialize at 0:
> 
> "
>  *
>  * There is no strict promise about the base, although it tends to start
>  * at 0 on boot (but people really shouldn't rely on that).
>  *
> "
> 
> Sasha, are you seeing any problem other than the apparent time jump?

Nope, but I've looked at it again and it seems that it jumps to the host's
clock (that is, in the example above the 3376355 value was the host's clock
value).


Thanks,
Sasha

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