Re: [PATCH v3 15/16] x86/VPMU: NMI-based VPMU support

[Boris Ostrovsky <boris.ostrovsky@oracle.com>]

On 01/16/2014 04:35 AM, Jan Beulich wrote:
>
>> +/* Process the softirq set by PMU NMI handler */
>> +static void pmu_softnmi(void)
>> +{
>> +    struct cpu_user_regs *regs;
>> +    struct vcpu *v, *sampled = per_cpu(sampled_vcpu, smp_processor_id());
>> +
>> +    if ( vpmu_mode & XENPMU_MODE_PRIV ||
>> +         sampled->domain->domain_id >= DOMID_FIRST_RESERVED )
>> +        v = dom0->vcpu[smp_processor_id()];
>> +    else
>> +        v = sampled;
>> +
>> +    regs = &v->arch.vpmu.xenpmu_data->pmu.regs;
>> +    if ( is_hvm_domain(sampled->domain) )
>> +    {
>> +        struct segment_register cs;
>> +
>> +        hvm_get_segment_register(sampled, x86_seg_cs, &cs);
>> +        regs->cs = cs.attr.fields.dpl;
>> +    }
>> +
>> +    send_guest_vcpu_virq(v, VIRQ_XENPMU);
>> +}
> Perhaps I should have asked this on an earlier patch already:
> How is this supposed to work for a 32-bit HVM guest?
> struct cpu_user_regs is clearly different for it than what the
> hypervisor or a 64-bit HVM guest would use.

Right, I need to XLAT_cpu_user_regs() for 32-bit HVM guest in 
vpmu_interrupt() (I already do it for a PV guest).

Thanks.
-boris