Re: [Qemu-devel] [PATCH 1/2] [RFC] Make vmport report the processor speed

[Alexander Graf]

Anthony Liguori wrote:
> Alexander Graf wrote:
>> If VMware ESX finds itself virtualized (read: inside VMware), it
>> reads the TSC speed
>> from its backdoor, because measuring the TSC inside a VM is not exact.
>>
>> This patch implements a hacky way to detect the TSC speed and passes
>> that through to
>> the VM. I am open to suggestions on how to improve the behavior.
>> It also adds a magic return value of 2 on the version return, which
>> is required by
>> VMware ESX.
>>
>> WARNING: This implementation breaks on non-x86 hosts!
>>   
>
> Have you tried just disabling vmport?

If I don't expose vmport or the command in that patch is not implemented
I get the following error when booting ESX:

Timer: InitPseudoTSC:3940: cpu 0: measured cpu and bus speeds conflict
(PR34866)
0:00:00:00.149 cpu0:1024)ALERT: Timer: InitPseudoTSC:3940: cpu 0:
measured cpu and bus speeds conflict (PR34866)
0:00:00:00.150 cpu0:1024)Timer: InitPseudoTSC:4002: node 0 (cpus 0-0):
consensus bus speed 1051144973 Hz
0:00:00:00.152 cpu0:1024)Timer: InitPseudoTSC:4047: TSC speed=2102289946
Hz, cpu speed=2102289946 Hz, bus speed=1051144973 Hz
0:00:00:00.153 cpu0:1024)Timer: InitPseudoTSC:4075: timerRCToTC
mult=0x1, shift=0, add=0x0
Init: VMKernel:811: Timer_InitPseudoTSC failed:0xbad00c1
0:00:00:00.155 cpu0:1024)ALERT: Init: VMKernel:811: Timer_InitPseudoTSC
failed:0xbad00c1

I don't really think we'll ever get timings accurate enough for such a
check.

Alex