On 26/01/2021 13:35, Jan Beulich wrote:
> On 21.01.2021 22:27, Andrew Cooper wrote:
>> --- a/xen/include/asm-x86/msr.h
>> +++ b/xen/include/asm-x86/msr.h
>> @@ -306,6 +306,38 @@ struct vcpu_msrs
>> };
>> } misc_features_enables;
>>
>> + /*
>> + * 0x00000560 ... 57x - MSR_RTIT_*
>> + *
>> + * "Real Time Instruction Trace", now called Processor Trace.
>> + *
>> + * These MSRs are not exposed to guests. They are controlled by Xen
>> + * behind the scenes, when vmtrace is enabled for the domain.
>> + *
>> + * MSR_RTIT_OUTPUT_BASE not stored here. It is fixed per vcpu, and
>> + * derived from v->vmtrace.buf.
>> + */
>> + struct {
>> + /*
>> + * Placed in the MSR load/save lists. Only modified by hypercall in
>> + * the common case.
>> + */
>> + uint64_t ctl;
> IIUC this field will be used by subsequent patches only?
Correct.
~Andrew
