Re: [PATCH v7 13/13] KVM: x86: Disable Intel Processor Trace when VMXON in L1 guest

[Paolo Bonzini]

On 04/05/2018 12:23, Alexander Shishkin wrote:
>> Currently, Intel Processor Trace do not support tracing in L1 guest
>> VMX operation(IA32_VMX_MISC[bit 14] is 0). As mentioned in SDM,
> I don't understand this patch. You mention VMX_MISC[14] here, but I
> can't see anything related to it in the code.

This is talking about the _guest_'s view of IA32_VMX_MISC.  The code
does nothing to set it, so the patch does what the commit message says
below:

>> on these type of processors, execution of the VMXON instruction will
>> clears IA32_RTIT_CTL.TraceEn and any attempt to write IA32_RTIT_CTL
>> causes a general-protection exception (#GP).
>>
>> Signed-off-by: Luwei Kang <luwei.kang@xxxxxxxxx>

Thanks,

Paolo